01949nas a2200265 4500008004100000022001400041245010200055210006900157260000900226300001200235490000600247520110500253100002201358700001501380700001901395700002101414700001901435700001501454700002801469700001601497700001701513700000501530700002501535856012301560 2021 eng d a2380-819500aOperando generated ordered heterogeneous catalyst for the selective conversion of CO2 to methanol0 aOperando generated ordered heterogeneous catalyst for the select cFEB  a509-5160 v63 a

The discovery of new materials for efficient transformation of carbon dioxide (CO2) into desired fuel can revolutionize large-scale renewable energy storage and mitigate environmental damage due to carbon emissions. In this work, we discovered an operando generated stable Ni-In kinetic phase that selectively converts CO2 to methanol (CTM) at low pressure compared to the state-of-the-art materials. The catalytic nature of a well-known methanation catalyst, nickel, has been tuned with the introduction of inactive indium, which enhances the CTM process. The remarkable change in the mechanistic pathways toward methanol production has been mapped by operando diffuse reflectance infrared Fourier transform spectroscopy analysis, corroborated by first-principles calculations. The ordered arrangement and pronounced electronegativity difference between metals are attributed to the complete shift in mechanism. The approach and findings of this work provide a unique advance toward the next-generation catalyst discovery for going beyond the state-of-the-art in CO2 reduction technologies.

1 aCherevotan, Arjun1 aRaj, Jithu1 aDheer, Lakshay1 aRoy, Soumyabrata1 aSarkar, Shreya1 aDas, Risov1 aVinod, Chathakudath, P.1 aXu, Shaojun1 aWells, Peter1 a1 aPeter, Sebastian, C. uhttps://library.ncl.res.in/content/operando-generated-ordered-heterogeneous-catalyst-selective-conversion-co2-methanol01879nas a2200289 4500008004100000022001400041245012100055210006900176260000800245300001200253490000700265520093700272653002001209653002101229653001401250653001901264653002101283653002101304100001901325700002001344700001601364700001501380700001801395700002301413700002501436856012801461 2021 eng d a2155-543500aUnveiling the roles of lattice strain and descriptor species on pt-like oxygen reduction activity in Pd-Bi catalysts0 aUnveiling the roles of lattice strain and descriptor species on  cJAN a800-8080 v113 a

A facile non-template-assisted mechanical ball milling technique was employed to generate a PdBi alloy catalyst. The induced lattice strain upon the milling time caused a shift of the d-band center, thereby enhancing the oxygen reduction reaction (ORR) catalytic activity. Additionally, the Pd-O reduction potential and adsorbed OH coverage used as descriptors stipulated the cause of the enhanced ORR activity upon the increased milling interval. Redox properties of surface Pd are directly correlated with a positive shift in the Pd-O reduction potential and OH surface coverage. Hence, by deconvoluting the lattice strain and the role of the descriptor species we achieved a catalyst system with a specific activity 5.4X higher than that of commercial Pt/C, as well as an improved durability. The experimental observation is well-corroborated by a theoretical simulation done by inducing strain to the system externally.

10acharge-transfer10aelectrocatalysis10afuel cell10aLattice strain10aoxygen reduction10aPt-like activity1 aSarkar, Shreya1 aRamarao, S., D.1 aDas, Tisita1 aDas, Risov1 aVinod, C., P.1 aChakraborty, Sudip1 aPeter, Sebastian, C. uhttps://library.ncl.res.in/content/unveiling-roles-lattice-strain-and-descriptor-species-pt-oxygen-reduction-activity-pd-bi01989nas a2200193 4500008004100000022001400041245014000055210006900195260000900264300001400273490000700287520127000294100001501564700001601579700001501595700002801610700002501638856013201663 2022 eng d a1754-569200aGreen transformation of CO2 to ethanol using water and sunlight by the combined effect of naturally abundant red phosphorus and Bi2MoO60 aGreen transformation of CO2 to ethanol using water and sunlight  cMAY  a1967-19760 v153 a

Direct photocatalytic conversion of CO2 to ethanol remains a scientific challenge because of the sluggish kinetics of C-C coupling and complex multielectron transfer processes. To achieve a green transformation of CO2 to C1+ products using naturally abundant sunlight and water requires the smart design of an efficient catalyst by selecting the right combination of atoms either in elemental or in compound form. Herein, we report a composite photocatalyst composed of earth abundant red phosphorus (RP) in nano-sheet morphology decorated with Bi2MoO6 nano-particles. The composite synthesised by a facile ultrasonication method produces 51.8 mu mol g(-1) h(-1) of ethanol from CO2. The ability of RP for the conversion of CO2 to C1 has been altered by the introduction of Bi2MoO6. In situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and Kinetic Isotopic Effect (KIE) analysis shed light on the mechanistic pathway, which propose that the presence of Bi-Mo dual sites play a crucial role in the C-C coupling toward the formation of ethanol. Spectroscopic evidence and isotope labeling experiments suggest that the intermediate OCH3* is the key active species for ethanol formation via self-coupling followed by proton transfer.

1 aDas, Risov1 aDas, Kousik1 aRay, Bitan1 aVinod, Chathakudath, P.1 aPeter, Sebastian, C. uhttps://library.ncl.res.in/content/green-transformation-co2-ethanol-using-water-and-sunlight-combined-effect-naturally-abundant02515nas a2200301 4500008004100000022001400041245012200055210006900177260000800246300001200254490000700266520151500273653002101788653002401809653001901833653002301852100001801875700001901893700002201912700001601934700001501950700002701965700003301992700001802025700002302043700002502066856012202091 2022 eng d a0935-964800aMorphology-tuned Pt3Ge accelerates water dissociation to industrial-standard hydrogen production over a wide pH range0 aMorphologytuned Pt3Ge accelerates water dissociation to industri cJUL a22022940 v343 a

The discovery of novel materials for industrial-standard hydrogen production is the present need considering the global energy infrastructure. A novel electrocatalyst, Pt3Ge, which is engineered with a desired crystallographic facet (202), accelerates hydrogen production by water electrolysis, and records industrially desired operational stability compared to the commercial catalyst platinum is introduced. Pt3Ge-(202) exhibits low overpotential of 21.7 mV (24.6 mV for Pt/C) and 92 mV for 10 and 200 mA cm(-2) current density, respectively in 0.5 m H2SO4. It also exhibits remarkable stability of 15 000 accelerated degradation tests cycles (5000 for Pt/C) and exceptional durability of 500 h (@10 mA cm(-2)) in acidic media. Pt3Ge-(202) also displays low overpotential of 96 mV for 10 mA cm(-2) current density in the alkaline medium, rationalizing its hydrogen production ability over a wide pH range required commercial operations. Long-term durability (>75 h in alkaline media) with the industrial level current density (>500 mA cm(-2)) has been demonstrated by utilizing the electrochemical flow reactor. The driving force behind this stupendous performance of Pt3Ge-(202) has been envisaged by mapping the reaction mechanism, active sites, and charge-transfer kinetics via controlled electrochemical experiments, ex situ X-ray photoelectron spectroscopy, in situ infrared spectroscopy, and in situ X-ray absorption spectroscopy further corroborated by first principles calculations.

10aElectrochemistry10ahydrogen production10aintermetallics10awater electrolysis1 aMondal, Soumi1 aSarkar, Shreya1 aBagchi, Debabrata1 aDas, Tisita1 aDas, Risov1 aSingh, Ashutosh, Kumar1 aPrasanna, Ponnappa, Kechanda1 aVinod, C., P.1 aChakraborty, Sudip1 aPeter, Sebastian, C. uhttps://library.ncl.res.in/content/morphology-tuned-pt3ge-accelerates-water-dissociation-industrial-standard-hydrogen02500nas a2200301 4500008004100000022001400041245012000055210006900175260000900244300001200253490000700265520151200272653001801784653002001802653001201822653001901834653001301853100001501866700001901881700001801900700002801918700002201946700002001968700002801988700002702016700002502043856013002068 2022 eng d a2155-543500aNoble-metal-free heterojunction photocatalyst for selective CO2 reduction to methane upon induced strain relaxation0 aNoblemetalfree heterojunction photocatalyst for selective CO2 re cJAN  a687-6970 v123 a

Sunlight-driven CO2 hydrogenation has drawn tremendous attention. However, selective CH4 formation via CO2 photoreduction is very challenging. Herein, we report a metal oxide semiconductor heterojunction consisting of BiVO4 and WO3 as a photocatalyst for the efficient conversion of carbon dioxide (CO2) selectively to methane (105 mu mol g(-1) h(-1)) under visible light in the absence of a sacrificial agent. Wise selection of the reaction medium and the strategically tuned heterojunction upon strain relaxation suppresses the competitive hydrogen generation reaction. The detailed photophysical, photoelectrochemical, and X-ray absorption spectroscopy studies pointed to the Z-scheme mechanism of electron transfer, which favors superior electron and hole separation compared to the individual components of the composite catalyst and other well-known photocatalysts reported for CO2 reduction. The observations are further corroborated by experimental diffuse reflectance infrared Fourier transform spectroscopy and theoretical density-functional theory calculations, which reveal that the heterojunction has a lower free-energy barrier for CO2 conversion to CH4 due to the larger stabilization of the *CH2O intermediate on the strain-relaxed heterojunction surface, in comparison to the pristine BiVO4 surface. The present work provides fundamental insights for constructing high-performance heterojunction photocatalysts for the selective conversion of CO2 to desired chemicals and fuels.

10aCO2 reduction10aheterostructure10amethane10aPhotocatalysis10aZ-scheme1 aDas, Risov1 aSarkar, Shreya1 aKumar, Ritesh1 aRamarao, Seethiraju, D.1 aCherevotan, Arjun1 aJasil, Mohammed1 aVinod, Chathakudath, P.1 aSingh, Abhishek, Kumar1 aPeter, Sebastian, C. uhttps://library.ncl.res.in/content/noble-metal-free-heterojunction-photocatalyst-selective-co2-reduction-methane-upon-induced02564nas a2200289 4500008004100000022001400041245013800055210006900193260000800262490000700270520158500277653001701862653002401879653001801903653001201921653001901933100001601952700001501968700001601983700001601999700002202015700002702037700002702064700002802091700002502119856013002144 2023 eng d a0935-964800aIntrinsic charge polarization in Bi19S27Cl3 nanorods promotes selective C-C coupling reaction during photoreduction of CO2 to ethanol0 aIntrinsic charge polarization in Bi19S27Cl3 nanorods promotes se cFEB0 v353 a

Obtaining multi-carbon products via CO2 photoreduction is a major catalytic challenge involving multielectron-mediated C-C bond formation. Complex design of multicomponent interfaces that are exploited to achieve this chemical transformation, often leads to untraceable deleterious changes in the interfacial chemical environment affecting CO2 conversion efficiency and product selectivity. Alternatively, robust metal centers having asymmetric charge distribution can effectuate C-C coupling reaction through the stabilization of intermediates, for desired product selectivity. However, generating inherent charge distribution in a single component catalyst is a difficult material design challenge. Here, a novel photocatalyst, Bi19S27Cl3, is presented which selectively converts CO2 to a C-2 product, ethanol, in high yield under visible light irradiation. Structural analysis through transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy reveals the presence of charge polarized bismuth centers in Bi19S27Cl3. The intrinsic electric field induced by charge polarized bismuth centers renders better separation efficiency of photogenerated electron-hole pair. Furthermore, charge polarized centers yield better adsorption of CO* intermediate and accelerate the rate determining C-C coupling step through the formation of OCCOH intermediate. Formation of these intermediates is experimentally mapped by in situ Fourier-transform infrared spectroscopy and further confirmed by theoretical calculation.

10aC-C coupling10acharge polarization10aCO2 reduction10aEthanol10aPhotocatalysis1 aDas, Kousik1 aDas, Risov1 aRiyaz, Mohd1 aParui, Arko1 aBagchi, Debabrata1 aSingh, Ashutosh, Kumar1 aSingh, Abhishek, Kumar1 aVinod, Chathakudath, P.1 aPeter, Sebastian, C. uhttps://library.ncl.res.in/content/intrinsic-charge-polarization-bi19s27cl3-nanorods-promotes-selective-c-c-coupling-reaction01871nas a2200265 4500008004100000022001400041245011700055210006900172260001100241490000700252520097200259653001701231653002401248653001801272653001901290100002601309700001501335700001601350700001601366700002701382700002201409700002801431700002501459856012101484 2023 eng d a1433-785100aWurtzite CuGaS2 with an in-situ-formed CuO layer photocatalyzes CO2 conversion to ethylene with high selectivity0 aWurtzite CuGaS2 with an insituformed CuO layer photocatalyzes CO cFEB 200 v623 a

We present surface reconstruction-induced C-C coupling whereby CO2 is converted into ethylene. The wurtzite phase of CuGaS2. undergoes in situ surface reconstruction, leading to the formation of a thin CuO layer over the pristine catalyst, which facilitates selective conversion of CO2 to ethylene (C2H4). Upon illumination, the catalyst efficiently converts CO2 to C2H4 with 75.1 % selectivity (92.7 % selectivity in terms of R-electron) and a 20.6 mu mol g(-1) h(-1) evolution rate. Subsequent spectroscopic and microscopic studies supported by theoretical analysis revealed operando-generated Cu2+, with the assistance of existing Cu+, functioning as an anchor for the generated *CO and thereby facilitating C-C coupling. This study demonstrates strain-induced in situ surface reconstruction leading to heterojunction formation, which finetunes the oxidation state of Cu and modulates the CO2 reduction reaction pathway to selective formation of ethylene.

10aC-C coupling10acharge polarization10aCO2 reduction10aPhotocatalysis1 aChakraborty, Subhajit1 aDas, Risov1 aRiyaz, Mohd1 aDas, Kousik1 aSingh, Ashutosh, Kumar1 aBagchi, Debabrata1 aVinod, Chathakudath, P.1 aPeter, Sebastian, C. uhttps://library.ncl.res.in/content/wurtzite-cugas2-situ-formed-cuo-layer-photocatalyzes-co2-conversion-ethylene-high02464nas a2200325 4500008004100000245014900041210006900190260000800259300001500267490000700282520139000289653001501679653001501694653001801709653001101727653001601738653001901754100001601773700002601789700001901815700002701834700001501861700001801876700001601894700001901910700002001929700002801949700002501977856013602002 2025 eng d00aDopant and exfoliation induced simultaneous modification of charge density and C―C coupling sites for efficient CO2 photoreduction to ethylene0 aDopant and exfoliation induced simultaneous modification of char cJUL ae2024234710 v643 a

The photochemical conversion of CO2 into C2+ products has emerged as an attractive method for synthesizing valuable chemicals and fuels using abundant solar energy. However, the challenge lies in enhancing the efficiency and selectivity of C2+ product formation. In this study, we employed a heteroatom doping strategy to optimize the photocatalytic parameters and achieve excellent efficiency and selectivity in the photocatalytic CO2 reduction to C2+ product formation. Our experimental analysis revealed that the local electronic structure of the catalyst, modified by In-doping, enables enhanced efficiency. Additionally, the incorporation of Cu facilitates the coupling of C1 intermediates, resulting in excellent selectivity towards C2+ products. The CO2 reduction performance is further enhanced through exfoliation, which increases the exposure of active sites and extends the charge carrier lifetime by reducing the charge diffusion length. We report that the rate of formation of C2H4 reached 54.3 mu molh(-1)g(-1) with an outstanding selectivity of 91% over the exfoliated CuIn-doped AgBiP2S6 catalyst. By elucidating the role of heteroatom doping and exfoliation in enhancing both the efficiency and selectivity of C2+ product formation, our study contributes to advancing the development of sustainable and efficient photocatalytic CO2 conversion technologies.

10aC & horbar10aC coupling10aCO2 reduction10aDoping10aExfoliation10aPhotocatalysis1 aDas, Kousik1 aChakraborty, Subhajit1 aKediya, Siddhi1 aSingh, Ashutosh, Kumar1 aDas, Risov1 aMondal, Soumi1 aRiyaz, Mohd1 aGoud, Devender1 aDutta, Nilutpal1 aVinod, Chathakudath, P.1 aPeter, Sebastian, C. uhttps://library.ncl.res.in/content/dopant-and-exfoliation-induced-simultaneous-modification-charge-density-and-c%E2%80%95c-coupling