Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Дек. 12, 2024

Rh-hydride phases were believed to be key causes of the exceptional catalytic ability Rh catalysts under H2 reductive conditions. Here, we utilize large-scale machine-learning-based global optimization explore millions bulk, surface, and nanoparticle structures in contact with H2, which rules out presence subsurface/interstitial H as thermodynamically stable ambient Instead, an Rh–H affinity is identified for surface atoms nanoparticles that can accommodate a high concentration adsorbed H, ratio reaching ∼2.5, featuring six-H-coordinated Rh, [RhH6]. Such [RhH6] species forming at edged sites are found intermediates electrochemical hydrogen evolution reaction (HER) on Rh. Guided by theory, our synthesized concave nanocubes density achieve Tafel slope 28.4 mV dec–1 low overpotential 36.1 jECSA = 1 mA cm–2, outperforms commercial Pt/C other morphologies catalysts. Our results clarify active phase nanosystems guide catalyst design precise morphology control nanocatalysts

Язык: Английский