A Ru atomic cluster-installed Co–Co2B nanocatalyst remarkably combats product inhibition while sustaining high turnover frequency of hydrogen production

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024-08, Vol.12 (31), p.20256-20269
• Main Authors: Borah, Rajani Kumar, Singh, Priti, Dixit, Mudit, Vernekar, Amit A
• Format: Article
• Language: English
• Subjects: Ammonia; Ammonium; Atomic clusters; Borates; Byproducts; Catalysis; Catalysts; Catalytic activity; Cluster analysis; Dehydrogenation; Economic impact; Frequency dependence; Hydrogen; Hydrogen production; Multitasking; Product inhibition; Reaction kinetics; Sustainable production
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d4ta03527e

Product inhibition poses a persistent challenge in catalysis, adversely affecting reaction rates and selectivity, leading to substantial economic losses in industrial settings. This phenomenon is particularly pronounced in sustainable hydrogen production, where byproduct-induced inhibition often obstructs catalyst regeneration and sustained catalytic activity. Despite numerous reports highlighting the issues associated with product inhibition, studies directly addressing this critical problem while maintaining a high turnover frequency (TOF) of the catalyst throughout the cycle remain unexplored. In this work, we have engineered a unique catalyst comprising Ru atomic clusters (ACs) installed on the surface of Co–Co2B (10% RuACs/Co–Co2B) that remarkably combats product inhibition by borates during ammonia borane (AB) dehydrogenation, while sustaining the catalyst's efficacy in hydrogen production throughout the reaction cycle. The hydrogen generation proceeds with a superior rate (26559.14 ± 169.67 mL min−1 gcat−1) and a high TOF (1032.2 ± 114.6 molH2 molRu−1 min−1) that dehydrogenates AB in only 9 s. Through a comprehensive analysis combining detailed experimental evidence, computational studies, and successive half-life analyses, we have uncovered significant charge reorganization between the Ru atomic clusters and the Co–Co2B support, which cooperatively facilitates rapid kinetics and greatly enhances the removal of the byproduct, ammonium tetramethoxyborate (AMB), from the catalyst's surface. This unique chemistry to combat product inhibition without compromising high rate and TOF distinguishes the 10% RuACs/Co–Co2B catalyst from others reported in the literature. Our findings not only hold significant promise for a sustainable hydrogen economy but open up avenues for the fundamental engineering of atomically clustered multitasking catalysts capable of addressing product inhibition in various crucial reactions.