02302nas a2200229 4500008004100000022001400041245012500055210006900180260000800249490000700257520147900264653001901743653002201762653002001784653003601804653002301840100001701863700002601880700002401906700001701930856012501947 2024 eng d a1439-423500aSize and morphology dependent activity of Cu clusters for CO2 activation and reduction: a first principles investigation0 aSize and morphology dependent activity of Cu clusters for CO2 ac cDEC0 v253 a

Various Cu-based materials in diverse forms have been investigated as efficient catalysts for electrochemical reduction of CO2; however, they suffer from issues such as higher over potential and poor selectivity. The activity and selectivity of CO2 electro reduction have been shown to change significantly when the surface morphology (steps, kinks, and edges) of these catalysts is altered. In light of this, size and morphology dependent activity of selected copper clusters, Cun (n=2-20) have been evaluated for the activation and reduction of CO2 molecule. The phase-space of these copper clusters is rich in conformations of distinct morphologies starting from planar, 2D geometries to prolate-shaped geometries and also high-symmetry structures. The binding efficiency and the activation of CO2 are highest for medium sized clusters (n=9-17) with prolate-morphologies as compared to small or larger sized CunCO(2) clusters that are existing mainly as planar (triangular, tetragonal etc.) or highly-symmetric geometries (icosahedron, capped-icosahedron etc.), respectively. The best performing (prolate-shaped) CunCO2 conformations are quite fluxional and also they are thermally stable, as demonstrated by the molecular dynamics simulations. Furthermore, on these CunCO(2) conformations, the step-by-step hydrogenation pathways of CO2 to produce value-added products like methanol, formic acid, and methane are exceptionally favorable and energy-efficient.

10aCO2 activation10aCO2 hydrogenation10aCopper clusters10aDensity Functional Theory (DFT)10amolecular dynamics1 aAmin, Seerat1 aKrishnamurty, Sailaja1 aDar, Manzoor, Ahmad1 aJoshi, Krati uhttps://library.ncl.res.in/content/size-and-morphology-dependent-activity-cu-clusters-co2-activation-and-reduction-first03165nas a2200157 4500008004100000022001400041245011300055210006900168260000800237490000600245520256000251100001702811700002602828700002402854856012902878 2025 eng d a2398-490200aBoosting the CO2 reduction activity of Cu double-atom catalysts through coordination environment engineering0 aBoosting the CO2 reduction activity of Cu doubleatom catalysts t cOCT0 v93 a

Double-atom catalysts (DACs) offer a reasonable and scalable route towards carbon neutrality owing to their efficient catalytic features. However, the challenges associated with the flexibility of their coordination structure usually restrict their full potential as efficient catalysts. Herein, we comprehensively examined the impact of coordination environment regulation on the CO2R activity of Cu2-DACs supported on C, N, or B co-doped graphene using ab initio simulations. We highlighted the marked role of the local coordination sphere of Cu2-DACs in modulating their structural stability and charge transfer characteristics, thereby regulating the adsorption of CO2 and various reaction characteristics. Notably, boron- and carbon-coordinated Cu2 centres (Cu2-BxCy) resulted in remarkably strong CO2 adsorption (-0.65 to -2.31 eV), attributed to their amplified electronic interactions with the CO2 molecule. The weak CO2 binding observed on the carbon-nitrogen- and nitrogen-boron-coordinated Cu2 centres (Cu2-NxCy and Cu2-NxBy) further highlighted the role of the coordination environment in facilitating the versatile binding modes of the key reaction species. The varying CO2 interactions in these systems were further comprehended and supported by a multilevel descriptor () combining both geometric and electronic parameters. This descriptor closely mirrored the DFT results, thereby accentuating its effectiveness as a predictive tool to perfectly model the CO2 interactions on these catalysts. Moreover, the dynamic behaviour in the adsorption modes led to partial breakdown of the conventional linear scaling relations between the key CO2 reduction intermediates (*COOH, *CO, and *HCO). Among the numerous types of investigated electrocatalysts, Cu2-B5C1 emerged as a highly active and selective catalyst for methanol production, with a remarkably low limiting potential of -0.54 V, surpassing the performance of several reported Cu-based systems. Besides, our findings underscored the often-overlooked yet crucial role of explicit solvation, which significantly altered both the potential-determining step and product selectivity. These outcomes emphasized the necessity of including solvation effects in realistic electrochemical modelling. Collectively, this study provides a critical mechanistic insight into better understanding the coordination effect on the CO2R and a robust design strategy for next-generation Cu-based DACs, guiding the development of highly efficient and selective catalysts for CO2 electroreduction.

1 aAmin, Seerat1 aKrishnamurty, Sailaja1 aDar, Manzoor, Ahmad uhttps://library.ncl.res.in/content/boosting-co2-reduction-activity-cu-double-atom-catalysts-through-coordination-environment02297nas a2200253 4500008004100000245015700041210006900198260000800267300001100275490000600286520134700292653003301639653003001672653003001702653003401732100001801766700001701784700002401801700002001825700002001845700002601865700002401891856012801915 2026 eng d00aElucidating the oxygen electrocatalytic activity of chromium cobalt spinel oxide supported over the spherical carbon for rechargeable zinc-air batteries0 aElucidating the oxygen electrocatalytic activity of chromium cob cMAY ae703360 v93 a

Cr1.5Co1.5O4 spinel nanoparticles supported over 3D spherical carbon (Cr1.5Co1.5O4/C-800) is synthesized as a bifunctional electrocatalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) for rechargeable zinc air battery (RZAB) applications. The incorporation of Cr into the spinel lattice and the decoration of the active material on a 3D spherical carbon support with intrinsic ORR activity and superior electrical conductivity enable uniform distribution of catalytically active sites, thereby improving bifunctional catalytic activity. The DFT studies were conducted to understand the role of the Cr in modulating the catalytic sites of the active material and to elucidate its effect on tuning the Co sites to enhance the activity. Half-cell studies show that Cr incorporation and spherical carbon support synergistically enhanced catalytic activity, with the Cr1.5Co1.5O4/C-800 catalyst demonstrating an onset potential of 0.93 V (70 mV lower than Pt/C) and an E & half; value of 0.70 V for ORR and an overpotential of 0.369 V at 20 mA cm-2 (eta 20) for OER (0.375 V for the RuO2 catalyst). The catalyst's bifunctional activity was validated in an RZAB, where it outperformed the Pt/C-RuO2 benchmark, delivering superior rate capability and stability and achieving a cycling life exceeding 145 h.

10achromium cobalt spinel oxide10aOxygen Evolution Reaction10aoxygen reduction reaction10arechargeable zinc-air battery1 aKurian, Maria1 aAmin, Seerat1 aPandikassala, Ajmal1 aManoj, Malavika1 aVijayan, Jubina1 aKrishnamurty, Sailaja1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/elucidating-oxygen-electrocatalytic-activity-chromium-cobalt-spinel-oxide-supported-over