02386nas 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<p>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.</p>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-002503nas 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<p>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.</p>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-n02277nas a2200289   4500008004100000022001400041245014000055210006900195260000800264300001400272490000600286520128800292653002001580653001401600653002601614653003001640653001001670100001801680700002701698700002401725700002401749700001801773700003001791700002101821700002001842856012501862       2018                        eng d  a2365-654900aMorphological ensembles of N-doped porous carbon derived from ZIF-8/Fe-graphene nanocomposites: processing and electrocatalytic studies0 aMorphological ensembles of Ndoped porous carbon derived from ZIF  cAUG  a8688-86970 v33 a<p>Engineering the active site density of porous carbon catalysts for enhanced electrocatalytic activity is the current focus in the quest for economically viable fuel cells. Herein, we synthesise ZIF-8/Fe-graphene composites for the formation of N and Fe co-doped carbon with diverse morphologies ranging from tubes and sheets to frameworks of carbon. A synthetic strategy involving the one pot synthesis of ZIF-8 based composites is accomplished by the reaction of 2-methylimidazole with mixed Zn/Fe salt solution containing graphene dispersions. The high temperature heat treatment of this precursor mix yielded micro-meso porous architectures of N, Fe co-doped carbon with dispersions of Fe/Fe3C. An onset potential value of 0.95 V and a half-wave potential of 0.82 V coupled with excellent durability and stability in alkaline medium indicated improved electrocatalytic performances over its commercial Pt/C counterpart. The appreciable electrocatalytic properties of the synthesized carbon are attributed to its morphological diversity, hybrid structure, high N doping and its heteroporous characteristics. The dispersed Fe/Fe3C and FeNx sites facilitated enhanced oxygen adsorption and the graphene inclusions in the composite provided retention of high nitrogen contents.</p>10aelectrocatalyst10afuel cell10aN- Fe co-doped carbon10aoxygen reduction reaction10aZIF-81 aThomas, Minju1 aIllathvalappil, Rajith1 aKurungot, Sreekumar1 aNair, Balagopal, N.1 aMohamed, Peer1 aAnilkumar, Gopinathan, M.1 aYamaguchi, Takeo1 aHareesh, U., S.  uhttps://library.ncl.res.in/content/morphological-ensembles-n-doped-porous-carbon-derived-zif-8fe-graphene-nanocomposites02390nas 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<p>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.</p>
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-reduction03376nas a2200337   4500008004100000022001400041245023000055210006900285260000800354490000700362520209900369653000702468653002602475653001402501653002702515653001802542653003002560653003002590653003402620653003402654100003002688700002002718700003302738700001802771700002702789700002002816700001802836700003602854700002402890856012402914       2024                        eng d  a1613-681000aAluminium, nitrogen-dual-doped reduced graphene oxide Co-existing with cobalt-encapsulated graphitic carbon nanotube as an activity modulated electrocatalyst for oxygen electrocatalyst for oxygen electrochemistry applications0 aAluminium nitrogendualdoped reduced graphene oxide Coexisting wi  cAUG0 v203 a<p>
	There is a rising need to create high-performing, affordable electrocatalysts in the new field of oxygen electrochemistry. Here, a cost-effective, activity-modulated electrocatalyst with the capacity to trigger both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) in an alkaline environment is presented. The catalyst (Al, Co/N-rGCNT) is made up of aluminium, nitrogen-dual-doped reduced graphene oxide sheets co-existing with cobalt-encapsulated carbon nanotube units. Based on X-ray Absorption Spectroscopy (XAS) studies, it is established that the superior reaction kinetics in Al, Co/N-rGCNT over their bulk counterparts can be attributed to their electronic regulation. The Al, Co/N-rGCNT performs as a versatile bifunctional electrocatalyst for zinc-air battery (ZAB), delivering an open circuit potential approximate to 1.35 V and peak power density of 106.3 mW cm-2, which are comparable to the system based on Pt/C. The Al, Co/N-rGCNT-based system showed a specific capacity of 737 mAh gZn-1 compared to 696 mAh gZn-1 delivered by the system based on Pt/C. The DFT calculations indicate that the adsorption of Co in the presence of Al doping in NGr improves the electronic properties favoring ORR. Thus, the Al, Co/N-rGCNT-based rechargeable ZAB (RZAB) emerges as a highly viable and affordable option for the development of RZAB for practical applications. This manuscript reports the development of a new bifunctional catalyst that exhibits high activity and stability under practical operating conditions. The catalyst (Al, Co/N-rGCNT) is made up of aluminium, nitrogen-dual-doped reduced graphene oxide sheets co-existing with the in situ formed cobalt-encapsulated CNT units is synthesized by a scalable pyrolysis method in an inert Ar atmosphere. The developed electrocatalyst achieved enhanced the oxygen reduction reaction (ORR) and the oxygen evolution reaction OER activity as a result of the favorable synergistic modulations and the system can serve as a process-friendly air-electrode for rechargeable zinc-air battery (RZAB). image</p>
10aAl10aBifunctional catalyst10aDFT study10aencapsulated structure10aN-dual doping10aOxygen Evolution Reaction10aoxygen reduction reaction10arechargeable zinc-air battery10aX-ray absorption spectroscopy1 aKharabe, Geeta, Pandurang1 aBarik, Sidharth1 aVeeranmaril, Sudheesh, Kumar1 aNair, Aathira1 aIllathvalappil, Rajith1 aYoyakki, Athira1 aJoshi, Kavita1 aVinod, Chathakudath, Prabhakara1 aKurungot, Sreekumar  uhttps://library.ncl.res.in/content/aluminium-nitrogen-dual-doped-reduced-graphene-oxide-co-existing-cobalt-encapsulated