02379nas a2200169 4500008004100000022001400041245014000055210006900195260007100264300001600335490000800351520166000359100002102019700002502040700002402065856012002089 2009 eng d a1932-744700aCarbon nanofiber with selectively decorated pt both on inner and outer walls as an efficient electrocatalyst for fuel cell applications0 aCarbon nanofiber with selectively decorated pt both on inner and a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcOCT a17572-175780 v1133 a

A novel electrocatalyst, with excellent Pi dispersion oil the inner and outer wall of a carbon nanofiber (CNF) was prepared by a modified polyol process in which both surface tension and polarity characteristics of the medium were properly adjusted to favor solution entry into the tubular region by capillary filling and homogeneous wetting of the inner wall surface by the solvents. The pristine CNF, which possesses an inherently active inner wall surface and inactive outer Wall surface, led to selective Pt deposition along the inner wall, whereas activation of the outer wall with chemical functionalization resulted in excellent dispersion of Pt along both inner and outer walls. Structural and morphological characterizations using high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) revealed that when Pt could be dispersed along the inner as well as the Outer walls of CNF, the Pt particle size decreased to almost half as compared to the one With Pt decoration only along a single wall of the Substrate material. Further, electrochemical studies using cyclic voltammetry (CV) and rotating disk electrode (RDE) measurements revealed enhanced methanol oxidation and oxygen reduction properties, respectively. The electrochemical active area obtained for the catalyst with both inner and outer wall Pt decoration wits nearly two times higher than that corresponding to the one with only inner wall Pt decoration. Similarly, the rate constant for the oxygen reduction reaction displayed by this sample was four times higher in comparison with the sample prepared by Utilizing only one wall for Pt decoration.

1 aBalan, Beena, K.1 aUnni, SreeKuttan, M.1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/carbon-nanofiber-selectively-decorated-pt-both-inner-and-outer-walls-efficient-002276nas a2200181 4500008004100000022001400041245010200055210006900157260011000226300001400336490000600350520152300356100002101879700002701900700002201927700002401949856012101973 2013 eng d a2046-206900aCarbon nanofiber-RuO2-poly(benzimidazole) ternary hybrids for improved supercapacitor performance0 aCarbon nanofiberRuO2polybenzimidazole ternary hybrids for improv aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcDEC a2428-24360 v33 a

Carbon nanofiber-RuO2-poly(benzimidazole) ternary hybrid electrode material which integrates dual wall decoration and interfacial area tuning for supercapacitor applications has been devised based on a simple approach. This is achieved by decorating RuO2 nanoparticles of size ca. 2-3 nm along the inner and outer walls of a hollow carbon nanofiber (CNF) support (F-20RuO(2)). In the next step, a proton conducting polymer, phosphoric acid doped polybenzimidazole (PBI-BuI), interface is created along the inner and outer surfaces of this material. A 103% increase in the specific capacitance is obtained for RuO2-PBI hybrid material as compared to that of F-20RuO(2) at the optimum level of the polymer wrapping. Apart from the high specific capacitance, the RuO2-PBI hybrid materials exhibit enhanced rate capability and excellent electrochemical stability of 98% retention in the capacitance. Such a remarkably high activity can be primarily attributed to the efficient dispersion of active sites achieved by properly utilizing inner and outer surfaces of CNF. Apart from this, the facile routes for ion transport created as a result of PBI incorporation coupled with excellent interfacial contact between the RuO2 and the electrolyte resulting in the improved utilization of the active material also contribute to the improved activity. In addition to this, the synergistic effects of pseudocapacitive contribution from both the PBI-BuI and RuO2 also contribute to the redefined performance characteristics.

1 aBalan, Beena, K.1 aChaudhari, Harshal, D.1 aKharul, Ulhas, K.1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/carbon-nanofiber-ruo2-polybenzimidazole-ternary-hybrids-improved-supercapacitor-001926nas a2200265 4500008004100000022001400041245012800055210006900183260007700252300001600329490000700345520092500352653002001277653003201297653002101329653002401350653001901374100001901393700003101412700002201443700002201465700002401487700002001511856012901531 2014 eng d a0947-653900aCovalent organic framework-cadmium sulfide hybrid as a prototype photocatalyst for visible-light-driven hydrogen production0 aCovalent organic frameworkcadmium sulfide hybrid as a prototype  aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcNOV a15961-159650 v203 a

CdS nanoparticles were deposited on a highly stable, two-dimensional (2D) covalent organic framework (COF) matrix and the hybrid was tested for photocatalytic hydrogen production. The efficiency of CdS-COF hybrid was investigated by varying the COF content. On the introduction of just 1 wt% of COF, a dramatic tenfold increase in the overall photocatalytic activity of the hybrid was observed. Among the various hybrids synthesized, that with 10 wt% COF, named CdS-COF (90: 10), was found to exhibit a steep H2 production amounting to 3678 mmolh(-1) g(-1), which is significantly higher than that of bulk CdS particles (124 mmolh(-1)g(-1)). The presence of a p-conjugated backbone, high surface area, and occurrence of abundant 2D hetero-interface highlight the usage of COF as an effective support for stabilizing the generated photoelectrons, thereby resulting in an efficient and high photocatalytic activity.

10acharge transfer10acovalent organic frameworks10ahybrid materials10ahydrogen production10aPhotocatalysis1 aThote, Jayshri1 aAiyappa, Harshitha, Barike1 aDeshpande, Aparna1 aDiaz, David, Diaz1 aKurungot, Sreekumar1 aBanerjee, Rahul uhttps://library.ncl.res.in/content/covalent-organic-framework-cadmium-sulfide-hybrid-prototype-photocatalyst-visible-light-001751nas a2200193 4500008004100000022001400041245007400055210006900129260011000198300001400308490000700322520100500329100002101334700001801355700002401373700002401397700002601421856011001447 2015 eng d a1466-803300aCan enantiomer ligands produce structurally distinct homochiral MOFs?0 aCan enantiomer ligands produce structurally distinct homochiral  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcSEP a8202-82060 v173 a

Here, we report a self-assembled homochiral metal-organic framework [Cu-1.5(H2LL-leu)(Ac)H2O](n)center dot 3H(2)O (1) obtained from an L-leucine-derived ligand (H4L(L-leu)) and Cu(Ac)(2)center dot H2O in a 1 : 1 ratio. Coordination-induced conformational change in the ligand has been monitored by circular dichroism which has been further attested by synthesizing a D-leucine-containing enantiomer H4L D-leu and its Cu(II) complex [Cu-1.5(H2LD-leu)H2O](n)center dot 10H(2)O (2). Structure determination revealed entirely different structures for the homochiral MOFs (1 and 2) obtained from the L/D-leucine-derived enantiomer ligands under analogous reaction conditions. Further, structural dissimilarity in these MOFs has been judicially supported by proton conductance studies. MOF 1 shows higher proton (10(-5) S cm(-1)) conductance in comparison to 2 (10(-6) S cm(-1)) due to dissimilar alignment of the hydrogen-bonded water molecules in the hydrophilic pocket as well as crystal packing.

1 aDubey, Mrigendra1 aKumar, Ashish1 aDhavale, Vishal, M.1 aKurungot, Sreekumar1 aPandey, Daya, Shankar uhttps://library.ncl.res.in/content/can-enantiomer-ligands-produce-structurally-distinct-homochiral-mofs-002386nas a2200253 4500008004100000022001400041245008400055210006900139260007100208300001600279490000600295520147900301653002101780653002001801653002001821653001401841653003001855100002501885700002701910700002801937700002701965700002401992856011602016 2015 eng d a1944-824400aCarbon nanohorn-derived graphene nanotubes as a platinum-free fuel cell cathode0 aCarbon nanohornderived graphene nanotubes as a platinumfree fuel a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcNOV a24256-242640 v73 a

Current low-temperature fuel cell research mainly focuses on the development of efficient nonprecious electrocatalysts for the reduction of dioxygen molecule due to the reasons like exorbitant cost and scarcity of the current state-of-the-art Pt-based catalysts. As a potential alternative to such costly electrocatalysts, we report here the preparation of an efficient graphene nanotube based oxygen reduction electrocatalyst which has been derived from single walled nanohorns, comprising a thin layer of graphene nanotubes and encapsulated iron oxide nanopartides (FeGNT). FeGNT shows a surface area of 750 m(2)/g, which is the highest ever reported among the metal encapsulated nanotubes. Moreover, the graphene protected iron oxide nanoparticles assist the system to attain efficient distribution of Fe-N-x and quaternary nitrogen based active reaction centers, which provides better activity and stability toward the oxygen reduction reaction (ORR) in acidic as well as alkaline conditions. Single cell performance of a proton exchange membrane fuel cell by using FeGNT as the cathode catalyst delivered a maximum power density of 200 mW cm(-2) with Nafion as the proton exchange membrane at 60 degrees C. The facile synthesis strategy with iron oxide encapsulated graphitic carbon morphology opens up a new horizon of hope toward developing Pt-free fuel cells and metal-air batteries along with its applicability in other energy conversion and storage devices.

10acarbon nanohorns10acarbon nanotube10aelectrocatalyst10afuel cell10aoxygen reduction reaction1 aUnni, SreeKuttan, M.1 aIllathvalappil, Rajith1 aBhange, Siddheshwar, N.1 aPuthenpediakkal, Hasna1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/carbon-nanohorn-derived-graphene-nanotubes-platinum-free-fuel-cell-cathode-001439nas a2200205 4500008004100000022001400041245012400055210006900179260007100248300001400319490000700333520063300340100001800973700002500991700002101016700002001037700002401057700002101081856013101102 2015 eng d a0020-166900aCoherent fusion of water array and protonated amine in a metal-sulfate-based coordination polymer for proton conduction0 aCoherent fusion of water array and protonated amine in a metalsu a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUN a5366-53710 v543 a

A new function of metal-sulfate-based co-ordination polymer (CP) for proton,conduction Was investigated through rational integration of a continuous water array and protonated amine in the coordination space of the CP. The H-bonded arrays of watet molecules along with nitrogen-rich aromatic cation (protonated melamine) facilitate proton conduction in the compound under humid conditions. Although several reports of metal-oxalate/phosphate-based CPs showing proton conduction are known, this is the first designed synthesis of a metal sulfate-based CP bearing-Water arrays functioning as a solid-state proton conductor:

1 aManna, Biplab1 aAnothumakkool, Bihag1 aDesai, Aamod, V.1 aSamanta, Partha1 aKurungot, Sreekumar1 aGhosh, Sujit, K. uhttps://library.ncl.res.in/content/coherent-fusion-water-array-and-protonated-amine-metal-sulfate-based-coordination-polymer-001962nas a2200241 4500008004100000022001400041245013300055210006900188260007500257300001400332490000600346520103800352653002101390653001801411653001501429653003001444653001301474100002501487700002901512700002401541700002601565856012901591 2015 eng d a2196-021600aCoSe2 supported on nitrogen-doped carbon nanohorns as a methanol-tolerant cathode for air-breathing microlaminar flow fuel cells0 aCoSe2 supported on nitrogendoped carbon nanohorns as a methanolt aPOSTFACH 101161, 69451 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcSEP a1339-13450 v23 a

The synthesis of CoSe2 nanoparticles supported on nitrogendoped carbon nanohorns (CoSe2/NCNH) and the influence of the interaction of the metal centre with the NCNH on the oxygen reduction reaction (ORR) are reported. CoSe2/NCNH shows a 50 mV lower onset overpotential and a 150 mV positive shift in the half-wave potential compared to CoSe2 supported on carbon and carbon nanohorns. This suggests that the intrinsic activity and the density of active reaction centres of CoSe2 are modified by NCNHs. An air-breathing direct meth-anol microlaminar flow fuel cell (mLFFC) is constructed using CoSe2/NCNH as a methanol-tolerant cathode catalyst. A maximum power density of 10.05 mWcm(-2) and a maximum current density of 124.20 mAcm(-2) are achieved with CoSe2/NCNH compared to the non-doped catalyst, CoSe2/C and Pt/C with 5m methanol as the fuel. The improved activity of CoSe2/ NCNH is attributed to the peculiar morphology and the nitrogen doping of the carbon nanohorns. This catalyst could be a suitable alternative to Pt.

10acarbon nanohorns10achalcogenides10afuel cells10aoxygen reduction reaction10aplatinum1 aUnni, SreeKuttan, M.1 aMora-Hernandez, Juan, M.1 aKurungot, Sreekumar1 aAlonso-Vante, Nicolas uhttps://library.ncl.res.in/content/cose2-supported-nitrogen-doped-carbon-nanohorns-methanol-tolerant-cathode-air-breathing-002350nas a2200241 4500008004100000022001400041245013100055210006900186260007100255300001400326490000600340520141500346653003301761653001901794653002001813653002601833653003001859653002401889653001901913100002401932700002401956856012801980 2015 eng d a2155-543500aCu-Pt nanocage with 3-D electrocatalytic surface as an efficient oxygen reduction electrocatalyst for a primary Zn-air battery0 aCuPt nanocage with 3D electrocatalytic surface as an efficient o a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcMAR a1445-14520 v53 a

Cu-Pt nanocage (CuPt-NC) intermetallic structures have been prepared by an in situ galvanic displacement reaction. The structures are found to be well organized within the framework demarcated with distinguishing arms, having clear edges and corners with a size of similar to 20 nm. The unique nanocage structure possessing large specific surface area and better structural integrity helps to achieve improved electrochemical oxygen reduction reaction activity and stability in alkaline solution in comparison to the commercially available 20 wt % Pt/C. CuPt-NC shows 50 mV positive onset potential shift with significantly higher limiting current in comparison to Pt/C. Interestingly, CuPt-NC has shown 2.9- and 2.5-fold improved mass activity and specific activity, respectively, for ORR at 0.9 V vs RHE in comparison to Pt/C. Moreover, the stability of CuPt-NC has been tested by an accelerated durability test under alkaline conditions. CuPt-NC has been subsequently utilized as the air electrode in a primary Zn-air battery and is found to possess 1.30- and 1.34-fold improved power density and current density at 1 V, respectively, in comparison to the state-of-the-art Pt/C catalyst. In addition, CuPt-NC has shown several hours of constant discharge stability at 20 mA cm(-2) with a specific capacity of 560 mAh gZn(-1) and energy density of 728 Wh kgZn(-1) in the primary Zn-air battery system.

10a3-D electrocatalytic surface10aCu-Pt nanocage10aelectrocatalyst10agalvanic displacement10aoxygen reduction reaction10asolvothermal method10aZn-air battery1 aDhavale, Vishal, M.1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/cu-pt-nanocage-3-d-electrocatalytic-surface-efficient-oxygen-reduction-electrocatalyst-001574nas a2200193 4500008004100000022001400041245009000055210006900145260007100214300001400285490000700299520083100306100003101137700001901168700002901187700002001216700002401236856012001260 2016 eng d a0897-475600aCobalt-modified covalent organic framework as a robust wateroxidation electrocatalyst0 aCobaltmodified covalent organic framework as a robust wateroxida a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUN a4375-43790 v283 a

The development of stable, efficient oxygen evolution reaction (OER) catalyst capable of oxidizing water is one of the premier challenges in the conversion of solar energy to electrical energy, because of its poor kinetics. Herein, a bipyridine-containing covalent organic framework (TpBpy) is utilized as an OER catalyst by way of engineering active Co(II) ions into its porous framework. The as-obtained Co-TpBpy retains a highly accessible surface area (450 m(2)/g) with exceptional stability, even after 1000 cycles and 24 h of OER activity in phosphate buffer under neutral pH conditions with an overpotential of 400 mV at a current density of 1 mA/cm(2). The unusual catalytic stability of Co-TpBpy arises from the synergetic effect of the inherent porosity and presence of coordinating units in the COF skeleton.

1 aAiyappa, Harshitha, Barike1 aThote, Jayshri1 aShinde, Digambar, Balaji1 aBanerjee, Rahul1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/cobalt-modified-covalent-organic-framework-robust-wateroxidation-electrocatalyst00941nas a2200181 4500008004100000022001400041245009800055210006900153260011000222300001200332490000700344520017600351100002300527700002700550700002400577700003000601856012800631 2016 eng d a1359-734500aConjugated porous polymers as precursors for electrocatalysts and storage electrode materials0 aConjugated porous polymers as precursors for electrocatalysts an aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcOCT a316-3180 v523 a

Conjugated porous polymers were used as precursors to prepare nitrogen and sulphur doped carbon atoms, which were then used for oxygen reduction and energy storage.

1 aBhosale, Manik, E.1 aIllathvalappil, Rajith1 aKurungot, Sreekumar1 aKrishnamoorthy, Kothandam uhttps://library.ncl.res.in/content/conjugated-porous-polymers-precursors-electrocatalysts-and-storage-electrode-materials-001904nas a2200205 4500008004100000022001400041245015400055210006900209260000800278300001400286490000700300520113000307100001701437700002601454700002301480700002401503700002101527700002101548856012901569 2016 eng d a1477-922600aCoordination polymers of Fe(III) and Al(III) ions with TCA ligand: distinctive fluorescence, CO2 uptake, redox-activity and oxygen evolution reaction0 aCoordination polymers of FeIII and AlIII ions with TCA ligand di cFEB a6901-69080 v453 a

Fe and Al belong to different groups in the periodic table, one from the p-block and the other from the d-block. In spite of their different groups, they have the similarity of exhibiting a stable 3+ oxidation state. Here we have prepared Fe(III) and Al(III) based coordination polymers in the form of metal-organic gels with the 4,4', 4 `'-tricarboxyltriphenylamine (TCA) ligand, namely Fe-TCA and Al-TCA, and evaluated some important physicochemical properties. Specifically, the electrical conductivity, redox-activity, porosity, and electrocatalytic activity (oxygen evolution reaction) of the Fe-TCA system were noted to be remarkably higher than those of the Al-TCA system. As for the photophysical properties, almost complete quenching of the fluorescence originating from TCA was observed in case of the Fe-TCA system, whereas for the Al-TCA system a significant retention of fluorescence with red-shifted emission was observed. Quantum mechanical calculations based on density functional theory (DFT) were performed to unravel the origin of such discriminative behaviour of these coordination polymer systems.

1 aDhara, Barun1 aSappati, Subrahmanyam1 aSingh, Santosh, K.1 aKurungot, Sreekumar1 aGhosh, Prasenjit1 aBallav, Nirmalya uhttps://library.ncl.res.in/content/coordination-polymers-feiii-and-aliii-ions-tca-ligand-distinctive-fluorescence-co2-uptake02503nas a2200289 4500008004100000022001400041245016700055210006900222260000800291300001400299490000600313520146900319653002001788653001401808653002201822653003001844100002501874700002701899700002401926700002401950700001801974700002101992700003002013700002002043700002002063856013002083 2017 eng d a2365-654900aChitosan intercalated metal organic gel as a green precursor of fe entrenched and fe distributed N-doped mesoporous graphitic carbon for oxygen reduction reaction0 aChitosan intercalated metal organic gel as a green precursor of  cSEP a8762-87700 v23 a

Herein, we present Metal-Organic Gel intercalated with chitosan, a `green'' precursor for the synthesis of intrinsic N-doped Fe entrenched (CHI-TMA-Fe-CW) and Fe distributed mesoporous graphitic carbon structures (CHI-TMA-Fe-CW-M1) with appreciable Oxygen Reduction Reaction (ORR) activity in alkaline medium. Modulation of the synthetic protocol as a function of reaction kinetics and gelation time while maintaining identical pyrolysis conditions (900 degrees C, flowing N-2 atmosphere) improves the microstructure, surface area and Fe distribution of the graphitic structures (CHI-TMA-Fe-CW-M1). CHI-TMA-Fe-CW has a Fe entrenched graphitic nanocapsule like morphology while Fe distributed mesoporous graphitic carbon sheets, with a specific surface area value of 565 m(2) g(-1) obtained by modulating the synthesis chemistry in CHI-TMA-Fe-CW-M1. The higher percentage of graphitic N in CHI-TMA-Fe-CW-M1 apparent from the XPS data validate that the modified synthetic method favours creation of more graphitic N sites contributing for better catalytic performance. CHI-TMA-Fe-CW-M1 catalyst exhibited comparable electrocatalytic activity with that of the commercially available Pt/C via an efficient four-electron-dominant ORR pathway with a positive onset potential value of 0.925 V vs RHE. Good durability of CHI-TMA-Fe-CW-M1 after 5000 cycles further confirm the prospects of MOG-chitosan and the feasibility to be used as a potential catalyst for ORR.

10aelectrocatalyst10afuel cell10aMetal-Organic-Gel10aoxygen reduction reaction1 aShijina, Kottarathil1 aIllathvalappil, Rajith1 aKurungot, Sreekumar1 aNair, Balagopal, N.1 aMohamed, Peer1 aYamaguchi, Takeo1 aAnilkumar, Gopinathan, M.1 aHareesh, U., S.1 aSailaja, G., S. uhttps://library.ncl.res.in/content/chitosan-intercalated-metal-organic-gel-green-precursor-fe-entrenched-and-fe-distributed-n02283nas a2200229 4500008004100000245009200041210006900133260000800202300001600210490000700226520149400233100002201727700002701749700001901776700002401795700002101819700002101840700002401861700002401885700002001909856012401929 2018 eng d00aConvergent covalent organic framework thin sheets as flexible supercapacitor electrodes0 aConvergent covalent organic framework thin sheets as flexible su cAUG a28139-281460 v103 aFlexible supercapacitors in modern electronic equipment require light-weight electrodes, which have a high surface area, precisely integrated redox moieties, and mechanically strong flexible free-standing nature. However, the incorporation of the aforementioned properties into a single electrode remains a great task. Herein, we could overcome these challenges by a facile and scalable synthesis of the convergent covalent organic framework (COF) free-standing flexible thin sheets through solid-state molecular baking strategy. Here, redox-active anthraquinone (Dq) and pi-electron-rich anthracene (Da) are judiciously selected as two different linkers in a beta-ketoenamine-linked two-dimensional (2D) COF. As a result of precisely integrated anthraquinone moieties, COF thin sheet exhibits redox activity. Meanwhile, pi-electron-rich anthracene linker assists to improve the mechanical property of the free-standing thin sheet through the enhancement of noncovalent interaction between crystallites. This binder-free strategy offers the togetherness of crystallinity and flexibility in 2D COF thin sheets. Also, the synthesized porous crystalline convergent COF thin sheets are benefited with crack-free uniform surface and light-weight nature. Further, to demonstrate the practical utility of the material as an electrode in energy-storage systems, we fabricated a solid-state symmetrical flexible COF supercapacitor device using a GRAFOIL peeled carbon tape as the current collector.1 aKhayum, Abdul, M.1 aVijayakumar, Vidyanand1 aKarak, Suvendu1 aKandambeth, Sharath1 aBhadra, Mohitosh1 aSuresh, Karthika1 aAcharambath, Nikhil1 aKurungot, Sreekumar1 aBanerjee, Rahul uhttps://library.ncl.res.in/content/convergent-covalent-organic-framework-thin-sheets-flexible-supercapacitor-electrodes02337nas a2200253 4500008004100000022001400041245017500055210006900230260000800299300001600307490000600323520138600329100002601715700002201741700002701763700002101790700001701811700002301828700002101851700002801872700002401900700003001924856012901954 2019 eng d a2470-134300aCarbon derived from soft pyrolysis of a covalent organic framework as a support for small-sized RuO2 showing exceptionally low overpotential for oxygen evolution reaction0 aCarbon derived from soft pyrolysis of a covalent organic framewo cAUG a13465-134730 v43 a

Electrochemical water splitting is the most energy-efficient technique for producing hydrogen and oxygen, the two valuable gases. However, it is limited by the slow kinetics of the anodic oxygen evolution reaction (OER), which can be improved using catalysts. Covalent organic framework (COF)-derived porous carbon can serve as an excellent catalyst support. Here, we report high electrocatalytic activity of two composites, formed by supporting RuO2 on carbon derived from two COFs with closely related structures. These composites catalyze oxygen evolution from alkaline media with overpotentials as low as 210 and 217 mV at 10 mA/cm(2), respectively. The Tafel slopes of these catalysts (65 and 67 mV/dec) indicate fast kinetics compared to commercial RuO2. The observed activity is the highest among all RuO2-based heterogeneous OER catalysts-a touted benchmark OER catalyst. The high catalytic activity arises from the extremely small-sized (similar to 3-4 nm) RuO2 nanoparticles homogeneously dispersed in a micro-mesoporous (BET = 517 m(2)/g) COF-derived carbon. The porous graphenic carbon favors mass transfer, while its N-rich framework anchors the catalytic nanoparticles, making it highly stable and recyclable. Crucially, the soft pyrolysis of the COF enables the formation of porous carbon and simultaneous growth of small RuO2 particles without aggregation.

1 aChakraborty, Debanjan1 aNandi, Shyamapada1 aIllathvalappil, Rajith1 aMullangi, Dinesh1 aMaity, Rahul1 aSingh, Santosh, K.1 aHaldar, Sattwick1 aVinod, Chathakudath, P.1 aKurungot, Sreekumar1 aVaidhyanathan, Ramanathan uhttps://library.ncl.res.in/content/carbon-derived-soft-pyrolysis-covalent-organic-framework-support-small-sized-ruo2-showing02899nas a2200205 4500008004100000245012800041210006900169260000800238300001600246490000700262520213600269100002502405700002702430700002302457700001802480700002402498700002402522700002502546856012202571 2019 eng d00aA copper(ii)-coordination polymer based on a sulfonic-carboxylic ligand exhibits high water-facilitated proton conductivity0 acopperiicoordination polymer based on a sulfoniccarboxylic ligan cAUG a11034-110440 v483 a

Proton conduction ability has been investigated in a new Cu(ii) based coordination polymer (CP), {[Cu-2(sba)(2)(bpg)(2)(H2O)(3)]center dot 5H(2)O}(n) (1), synthesized using the combination of 4-sulfobenzoic acid (4-Hsba) and bipyridine-glycoluril (BPG) ligands. Single crystal X-ray structure determination revealed that 1 features 1D porous channels encapsulating a continuous array of water molecules. Proton conductivity measurements reveal a high conductivity value of 0.94 x 10(-2) S cm(-1) at 80 degrees C and 95% RH. The activation energy (E-a) of 0.64 eV demonstrates that the solvate water, coordinated water and hydrophilic groups in the channels promote the mobility of protons in the framework. Water sorption measurements exhibited hysterical behaviour with a high uptake value of 379.07 cm(3) g(-1). Time-dependent measurements revealed that the proton conductivity is retained even after 12 h of measurements. The proton conduction mechanism was validated by ab initio electronic structure calculations using the Nudged Elastic Band (NEB) method with molecular dynamics (MD) simulation studies. The theoretical activation energy is calculated to be 0.54 eV which is in accordance with the experimental value.

1 aTayade, Sakharam, B.1 aIllathvalappil, Rajith1 aLapalikar, Vaidehi1 aMarkad, Datta1 aKurungot, Sreekumar1 aPujari, Bhatchandra1 aKumbhar, Avinash, S. uhttps://library.ncl.res.in/content/copperii-coordination-polymer-based-sulfonic-carboxylic-ligand-exhibits-high-water01991nas a2200265 4500008004100000022001400041245012300055210006900178260000900247300001400256490000700270520109400277653004101371653002101412653001601433653000801449653002001457100001601477700001101493700002801504700002001532700002401552700001801576856013101594 2019 eng d a1867-388000aCubic palladium nanorattles with solid octahedron gold core for catalysis and alkaline membrane fuel cell applications0 aCubic palladium nanorattles with solid octahedron gold core for  cSEP  a4383-43920 v113 a

Herein, we report the synthesis of palladium nanorattles (Au-Pd NRTs) comprising of a gold octahedral core caged within a thin porous cubic palladium shell. The introduction of core-shell and porous architecture was realized by combining seed mediated and galvanic replacement reaction techniques. Next, we examined the catalytic efficiency of the nanocatalyst in comparison with solid palladium nanocube (Pd-NC) of similar size for the degradation of p-nitrophenol and organic dyes. The rate constant of Au-Pd NRTs was found nearly 12 times higher than the Pd-NCs. Further, we exploited our catalyst for electrochemical oxygen reduction reaction (ORR) and observed its high intrinsic ORR activity. Compared with commercialized Pt/C, the Au-Pd NRT displayed nearly comparable onset and half-wave potential values and excellent durability upon potential cycling. The system level validation in a single-cell mode of alkaline exchange membrane fuel cell also confirms the efficiency of the present catalyst to serve as a potential cathode catalyst for realistic device applications.

10aalkaline exchange membrane fuel cell10aelectrocatalysis10ananorattles10aORR10aPd nanoparticle1 aSingh, Prem1 aSonika1 aGangadharan, Pranav, K.1 aKhan, Ziyauddin1 aKurungot, Sreekumar1 aJaiswal, Amit uhttps://library.ncl.res.in/content/cubic-palladium-nanorattles-solid-octahedron-gold-core-catalysis-and-alkaline-membrane-fuel02390nas a2200217 4500008004100000022001400041245015200055210006900207260000800276300001400284490000600298520158300304653001901887653001501906653001801921653002601939653003001965100002701995700002402022856012602046 2020 eng d a2196-021600aCo (9) S (8) nanoparticle-supported nitrogen-doped carbon as a robust catalyst for oxygen reduction reaction in both acidic and alkaline conditions0 aCo 9 S 8 nanoparticlesupported nitrogendoped carbon as a robust  cJUL a3123-31340 v73 a

The present work illustrates the synthesis of an efficient and durable catalyst for electrochemical oxygen reduction reaction (ORR) which is active both in the alkaline and acidic conditions by dispersing few-layer graphitic carbon coated Co(9)S(8)nanoparticles on the nitrogen-doped carbon (NVC-G) support (Co9S8/NVC-G). The size of the Co(9)S(8)nanoparticles is nearly 7-8 nm and the particles are found to be dispersed homogeneously on the NVC-G support. The few-layer graphitic carbon formed on the surface of Co(9)S(8)nanoparticles is assisting to accomplish their small size and it also prevents agglomeration of the nanoparticles. The ORR activity of the obtained material was analyzed in both 0.1 M KOH and 0.5 M H(2)SO(4)solutions. Co9S8/NVC-G displays nearly 70 mV overpotential compared to thestate-of-the-artPt/C in 0.1 M KOH solution. The half-wave potential (E-1/2) difference of the present system is nearly 75 mV with the commercial Pt/C. Co9S8/NVC-G displays promising ORR activity in the acidic conditions as well with nearly 140 mV overpotential compared to its Pt/C counterpart. The system shows about 170 mV lowerE(1/2)value with Pt/C. The system shows good stability both in acidic and basic conditions compared to the Pt/C system. Finally, testing of a single cell of a polymer electrolyte membrane fuel cell (PEMFC) was performed by employing Co9S8/NVC-G as the cathode catalyst and Nafion-212 as the proton exchange membrane. The system displays a maximum power density of 245 mW cm(-2)in H-2-O(2)and 115 mW cm(-2)in H-2-air feeding conditions.

10acobalt sulfide10afuel cells10aNanoparticles10anitrogen-doped carbon10aoxygen reduction reaction1 aIllathvalappil, Rajith1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/co-9-s-8-nanoparticle-supported-nitrogen-doped-carbon-robust-catalyst-oxygen-reduction02194nas a2200241 4500008004100000022001400041245016800055210006900223260000800292300001400300490000600314520127100320653002201591653002401613653002601637653003201663653003001695100002001725700003001745700002701775700002401802856012601826 2020 eng d a2196-021600aCo@CoAl-layered double hydroxide/nitrogen-doped graphene composite catalyst for Al-H2O-based batteries: simultaneous hydrogen production and electricity generation0 aCoCoAllayered double hydroxidenitrogendoped graphene composite c cJUN a2582-25910 v73 a

Currently, the low energy efficiency of water electrolysis has compelled research toward the development of novel and energy-effective strategies for low-cost H-2 generation. In this context, we report a new concept of simultaneous H-2 and electricity generation by separating out the exothermic self-sustained Al-H2O reaction via electrochemistry. In addition, to catalyze the cathodic water reduction reaction, a single-pot and environmentally benign synthesis method is adopted. It results in the design of an electrocatalyst composed of Co@CoAl-layered double hydroxide core-shell nanospheres anchored over in situ generated N-doped graphene. Toward the water reduction reaction, the designed catalyst shows a negative voltage shift of mere around 113 mV with respect to the commercial Pt/C catalyst to reach the benchmark 10 mA cm(-2), with excellent stability of approximately 86 % voltage retention after 12 h of continuous operation. The catalytic superiority of our material is evident when taken for battery-level testing; the fabricated device was able to deliver an average output voltage of around 0.95 V at a discharge current density of 5 mA cm(-2) along with H-2 liberation, which was also detected and quantified through gas chromatography.

10aAl-H2O fuel cells10achronopotentiometry10acore-shell structures10ahydrogen evolution reaction10alayered double hydroxides1 aNadeema, Ayasha1 aKharabe, Geeta, Pandurang1 aBiswal, Dibya, Prakash1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/cocoal-layered-double-hydroxidenitrogen-doped-graphene-composite-catalyst-al-h2o-based02600nas a2200265 4500008004100000022001400041245017300055210006900228260000800297300001600305490000700321520162900328653003101957653002201988653002302010653002202033653002002055100002102075700002402096700002402120700002402144700001802168700002402186856012402210 2022 eng d a1944-824400aCo-Ni layered double hydroxide for the electrocatalytic oxidation of organic molecules: an approach to lowering the overall cell voltage for the water splitting process0 aCoNi layered double hydroxide for the electrocatalytic oxidation cAPR a16222-162320 v143 a

Electrocatalytic oxidation of simple organic molecules oilers a promising strategy to combat the sluggish kinetics of the water oxidation reaction (WOR). The low potential requirement, inhibition of the crossover of gases, and formation of value-added products at the anode are benefits of the electrocatalytic oxidation of organic molecules. Herein, we developed cobalt-nickel-based layered double hydroxide (LDH) as a robust material for the electrocatalytic oxidation of alcohols and urea at the anode, replacing the WOR. A facile synthesis protocol to form LDHs with different ratios of Co and Ni is adapted. It demonstrates that the reactants could be efficiently oxidized to concomitant chemical products at the anode. The half-cell study shows an onset potential of 1.30 V for benzyl alcohol oxidation reaction (BAOR), 1.36 V for glycerol oxidation reaction (GOR), 1.33 V for ethanol oxidation reaction (EOR), and 1.32 V for urea oxidation reaction (UOR) compared with 1.53 V for WOR. Notably, the hybrid electrolyzer in a full-cell configuration significantly reduces the overall cell voltage at a 20 mA cm(-2) current density by similar to 15% while coupling with the BAOR, EOR, and GOR and similar to 12% with the UOR as the anodic half-cell reaction. Furthermore, the efficiency of hydrogen generation remains unhampered with the types of oxidation reactions (alcohols and urea) occurring at the anode. This work demonstrates the prospects of lowering the overall cell voltage in the case of a water electrolyzer by integrating the hydrogen evolution reaction with suitable organic molecule oxidation.

10aelectrocatalytic oxidation10aenergy conversion10aimidazole mediated10aLayered compounds10awater splitting1 aShilpa, Nagaraju1 aPandikassala, Ajmal1 aKrishnaraj, Perayil1 aWalko, Priyanka, S.1 aDevi, Nandini1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/co-ni-layered-double-hydroxide-electrocatalytic-oxidation-organic-molecules-approach01911nas a2200301 4500008004100000022001400041245007100055210006900126260000900195490000700204520095100211653002301162653001801185653002401203653003801227653002601265653002401291100002801315700001601343700002401359700002601383700001601409700001901425700001601444700002401460700001901484856010601503 2023 eng d a1433-785100aChemically gradient hydrogen-bonded organic framework crystal film0 aChemically gradient hydrogenbonded organic framework crystal fil cJUL 0 v623 a

Hydrogen-bonded organic frameworks (HOFs) are ordered supramolecular solid structures, however, nothing much explored as centimetre-scale self-standing films. The fabrication of such crystals comprising self-supported films is challenging due to the limited flexibility and interaction of the crystals, and therefore studies on two-dimensional macrostructures of HOFs are limited to external supports. Herein, we introduce a novel chemical gradient strategy to fabricate a crystal-deposited HOF film on an in situ-formed covalent organic polymer film (Tam-Bdca-CGHOF). The fabricated film showed versatility in chemical bonding along its thickness from covalent to hydrogen-bonded network. The kinetic-controlled Tam-Bdca-CGHOF showed enhanced proton conductivity (8.3x10(-5) S cm(-1)) compared to its rapid kinetic analogue, Tam-Bdca-COP (2.1x10(-5) S cm(-1)), which signifies the advantage of bonding-engineering in the same system.

10aChemical Gradience10aCrystal Films10aFree-Standing Films10ahydrogen-bonded organic framework10aInterfacial Chemistry10aproton conductivity1 aMohammed, Abdul, Khayum1 aRaya, Jesus1 aPandikassala, Ajmal1 aAddicoat, Matthew, A.1 aGaber, Safa1 aAslam, Mohamed1 aAli, Liaqat1 aKurungot, Sreekumar1 aShetty, Dinesh uhttps://library.ncl.res.in/content/chemically-gradient-hydrogen-bonded-organic-framework-crystal-film02763nas a2200229 4500008004100000022001400041245017600055210006900231260000800300300001400308490000600322520188200328100003002210700002702240700002002267700002702287700002402314700002102338700001802359700002402377856013202401 2023 eng d a2398-490200aCobalt-manganese modified theophrastite phase of nickel hydroxide nanoflower arrays on nickel foam as a self-standing bifunctional electrode for overall water electrolysis0 aCobaltmanganese modified theophrastite phase of nickel hydroxide cMAY a2428-24400 v73 a

Designing and developing self-supported electrodes for water electrolysis is attractive as compared to conventional catalyst-coated electrodes. Herein, a (Co0.3Mn0.1Ni0.6)(OH)(2)/NF nanocomposite is prepared by anchoring (Co0.3Mn0.1Ni0.6)(OH)(2)via simple one-pot hydrothermal synthesis on nickel foam. The presence of Mn induces the external electronic structure of Co(OH)(2), and this also improves the electrochemically active surface area (ECSA). These favor better accessibility of active sites and increased intrinsic activity for the OER and HER. (Co0.3Mn0.1Ni0.6)(OH)(2)/NF has shown promising electrochemical activity toward the OER and HER in a 1 M KOH electrolyte, with an overpotential of 270 mV for the OER and 163 mV for the HER to deliver 10 mA cm(-2) current density. The overall water splitting was performed by employing (Co0.3Mn0.1Ni0.6)(OH)(2)/NF as both the cathode and anode by displaying a voltage of 1.62 V at 10 mA cm(-2), which is comparable to that extracted from a similar system based on the state-of-the-art Pt/C@NF cathode and RuO2@NF anode (1.60 V at 10 mA cm(-2)) standard electrode pair. Interestingly, at high current densities, the (Co0.3Mn0.1Ni0.6)(OH)(2)/NF//(Co0.3Mn0.1Ni0.6)(OH)(2)/NF system displayed better overall water splitting performance (1.78 V at 100 mA cm(-2)) compared to its Pt/C@NF//RuO2@NF (1.89 V at 100 mA cm(-2)) counterpart while displaying a stable output during the evolution period that lasted for 24 h. The amounts of H-2 and O-2 produced are estimated to be 701.2 and 358.6 mmol, respectively, at a time interval of 1 h; these amounts correspond to an similar to 1 : 2 ratio of O-2 and H-2, respectively. This study confirms the capability for employing (Co0.3Mn0.1Ni0.6)(OH)(2)/NF as a bi-functional and self-standing electrode for the realistic demonstrations of overall water splitting applications.

1 aKharabe, Geeta, Pandurang1 aIllathvalappil, Rajith1 aBarik, Sidharth1 aKanheerampockil, Fayis1 aWalko, Priyanka, S.1 aBhat, Suresh, K.1 aDevi, Nandini1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/cobalt-manganese-modified-theophrastite-phase-nickel-hydroxide-nanoflower-arrays-nickel-foam02464nas a2200265 4500008004100000022001400041245019400055210006900249260000800318300001200326490000700338520138600345653004101731653002401772653003001796653003301826653002701859653005301886100004001939700001701979700001901996700002702015700002402042856013202066 2024 eng d a1613-681000aCathode|electrolyte interface engineering by a hydrogel polymer electrolyte for a 3D porous high-voltage cathode material in a quasi-solid-state zinc metal battery by in situ polymerization0 aCathodeelectrolyte interface engineering by a hydrogel polymer e cOCT a24031580 v203 a

This work highlights the development of a superior cathode|electrolyte interface for the quasi solid-state rechargeable zinc metal battery (QSS-RZMB) by a novel hydrogel polymer electrolyte using an ultraviolet (UV) light-assisted in situ polymerization strategy. By integrating the cathode with a thin layer of the hydrogel polymer electrolyte, this technique produces an integrated interface that ensures quick Zn2+ ion conduction. The coexistence of nanowires for direct electron routes and the enhanced electrolyte ion infiltration and diffusion by the 3D porous flower structure with a wide open surface of the Zn-MnO electrode complements the interface formation during the in situ polymerization process. The QSS-RZMB configured with an integrated cathode (i-Zn-MnO) and the hydrogel polymer electrolyte (PHPZ-30) as the separator yields a comparable specific energy density of 214.14 Wh kg(-1) with that of its liquid counterpart (240.38 Wh kg(-1), 0.5 M Zn(CF3SO3)(2) aqueous electrolyte). Other noteworthy features of the presented QSS-RZMB system include its superior cycle life of over 1000 charge-discharge cycles and 85% capacity retention with 99% coulombic efficiency at the current density of 1.0 A g(-1), compared to only 60% capacity retention over 500 charge-discharge cycles displayed by the liquid-state system under the same operating conditions.

10acathode-electrolyte interface tuning10adendrite inhibition10aepitaxial zinc deposition10ahydrogel polymer electrolyte10aIn situ polymerization10aQuasi solidstate rechargeable zinc metal battery1 aPuthiyaveetil, Priyanka, Pandinhare1 aTorris, Arun1 aDilwale, Swati1 aKanheerampockil, Fayis1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/cathodeelectrolyte-interface-engineering-hydrogel-polymer-electrolyte-3d-porous-high-voltage02165nas a2200205 4500008004100000022001400041245012400055210006900179260000900248300001400257490000700271520139800278100002301676700003001699700002001729700001801749700002401767700003801791856013001829 2024 eng d a0887-062400aCo-incorporated N-doped micro-meso porous carbon as an electrocatalyst for oxygen reduction reaction and Zn-air battery0 aCoincorporated Ndoped micromeso porous carbon as an electrocatal cAPR  a7196-72070 v383 a

Metal-organic frameworks are considered ideal precursors for the preparation of transition-metal, heteroatom-doped carbon catalysts that are perceived to be efficient electrocatalysts for energy storage devices. Herein, we demonstrate the synthesis of ZIF-67-derived Co-incorporated N-doped porous carbon catalysts supported on high surface area microporous carbon prepared from a lotus seed shell. The combination of the two carbon catalysts in different weight ratios resulted in Co-incorporated N-doped carbon sheets with tuned surface area and porosity, enabling enhanced oxygen reduction reaction (ORR) activity in an alkaline medium. The optimized carbon catalyst ZL 600 (3:1) exhibited a half-wave potential of 0.79 V vs RHE and a limiting current density of -4.38 mA cm(-2) in 0.1 M KOH solution with higher stability and methanol tolerance. The optimized sample ZL 600 (3:1) demonstrated as a cathode in a zinc-air battery exhibited an open circuit voltage of 1.29 V with a flat discharge profile at a current rate of 10 mA cm(-2). The homemade system produced a specific capacity of 610 mAh g(-1) and a peak power density of 111 mW cm(-2), comparable to the cathode made with Pt/C. The high micro-mesoporosity, pyridinic and pyrrolic nitrogen contents, as well as enriched Co-active centers protected by carbon sheets favorably contributed to the efficient ORR mechanism.

1 aPriya, Vaishna, K.1 aKharabe, Geeta, Pandurang1 aBarik, Sidharth1 aMohamed, Peer1 aKurungot, Sreekumar1 aHareesh, Unnikrishnan, Nair Saras uhttps://library.ncl.res.in/content/co-incorporated-n-doped-micro-meso-porous-carbon-electrocatalyst-oxygen-reduction-reaction02266nas a2200217 4500008004100000022001400041245012100055210006900176260000900245300001400254490000700268520147700275653004101752653002801793653001901821653001501840653002101855100001901876700002401895856012901919 2024 eng d a2050-748800aConductive metal-organic frameworks for zinc-air battery application: design principles, recent trends and prospects0 aConductive metalorganic frameworks for zincair battery applicati cJAN  a2605-26190 v123 a

Electrochemical energy conversion and storage systems have an indispensable place in the modern world to fulfill the increasing energy demands. Among the different storage devices, rechargeable zinc-air batteries (ZABs) have become one of the most promising energy technologies owing to the abundance and inexpensiveness of Zn, simple operation, environmental friendliness, and reasonable energy density. However, the sluggishness of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) occurring in ZABs is a serious obstacle in their progress and commercialization. This creates a need for the development of efficient bifunctional electrocatalysts for ORR and OER. Conductive metal-organic frameworks (cMOFs) imbibing the general properties of MOFs, like high surface area, tunable porosity, redox-active centers, and additional intrinsic conductivity, can be a very lucrative option for developing bifunctional ORR and OER electrocatalysts for ZAB applications. In this review, we discuss the conductivity and design strategies of conductive MOFs, the basic configuration of ZABs, and the use of cMOFs for ZAB applications. The future directions for the improvement of cMOFs for ZABs have been provided, which hopefully will incite interest among researchers for further exploring cMOFs for ZABs. Electrochemical energy conversion and storage systems have an indispensable place in the modern world to fulfill the increasing energy demands.

10aBiofunctional Oxygen Electrocatalyst10aElectrical conductivity10aEnergy storage10aFuel-Cells10ali-ion batteries1 aDevi, Bandhana1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/conductive-metal-organic-frameworks-zinc-air-battery-application-design-principles-recent