Selective Facet Engineering of Ni<sub>12</sub>P<sub>5</sub> Nanoparticle for Maximization of Electrocatalytic Oxidative Reaction of Biomass Chemicals
Souradip Ganguly, Jyotishman Kaishyop, Tuhin Suvra Khan, SK Tarik Aziz, Arnab Dutta, Chanchal Loha, Sirshendu Ghosh
Abstract
Electrocatalytic hydrogen generation is a prime research topic for the large-scale production of hydrogen fuel. High energy demanding oxygen evolution process impedes the production of H 2 at low potentials. Conversion of biomass to value-added chemicals or fuels is appraised as an upcycling process, which is advantageous for resource management. Coupling of hydrogen generation at the cathode with oxidative conversion of biomass to market-demanded chemicals at the anode is a sustainable approach to increase energy efficiency in hybrid electrolysis. For that purpose, Ni-based anode electrocatalysts are in the forefront for ease of formation of hypervalent Ni III species, at a mild anodic potential, which act as an oxidant to propagate the oxidation and dehydrogenation reactions. Herein, we synthesized Ni 12 P 5 nanohexagon via kinetic stabilization of high index { 4 25 ¯ } facets and compared the electrocatalytic activity toward various biomass-derived platform chemicals oxidation with the thermodynamically stable Ni 12 P 5 nanosphere. The Ni 12 P 5 nanohexagon outperforms the current state-of-the-art catalysts regarding mass activity, product conversion, and Faradaic yield. Ease of formation of active species, faster charge transfer, and enhanced adsorption of substrates over { 4 25 ¯ } facets resulted in this superior activity. This shape-directing effects on Ni 12 P 5 ensured potential advantage of 150 mV in hybrid electrolysis over water splitting reaction when ethanol was used as a substrate in a two-electrode electrolyzer cell.