Accelerating H* Redistribution via Hydrogen Spillover for Enhanced Electrochemical Hydrogen Production From Formaldehyde
Xuanni Lin, Xi Chen, Qiannan Liu, Zhengfei Chen, Weixiao Lin, Cheng‐Jie Yang, Xiahan Sang, Zhongjian Li, Bin Yang, Chung‐Li Dong, Qiang Zhou, Lecheng Lei, Ming Qiu, Liming Dai, Yang HouABSTRACT
Producing hydrogen from formaldehyde oxidation reaction (FOR) offers a promising low‐energy approach for generating clean fuel. However, the FOR involves continuous C─H bond cleavage of adsorbed intermediates to generate abundant surface H*. This necessitates rapid transfer and consumption of H* to sustain fast oxidation kinetics. Herein, we developed a hydrogen‐spillover strategy to redistribute these surface H* to accelerate FOR kinetics by constructing RhCu single‐atom alloy supported on a Cu single‐atom‐rich carbon matrix (RhCu@Cu SA NC). In this design, Cu incorporation creates a favorable landscape for H* migration toward the Cu SA NC support, which acts as efficient H* acceptors and H─H coupling centers. Verified through multiple analyses, this hydrogen‐spillover mechanism is demonstrated to enhance FOR activity by accelerating H* redistribution. Consequently, RhCu@Cu SA NC shows outstanding FOR performance, achieving a current density of 800 mA cm − 2 at 0.39 V with nearly 100% H 2 selectivity and excellent durability. When integrated into a hybrid alkali‐acid cell, it provides an open circuit voltage of 1.72 V and peak power density of 152.6 mW cm − 2 with stable H 2 production for over 1200 h at 10 mA cm − 2 . These results demonstrate that hydrogen spillover boosts oxidative electrocatalysis, providing a general design principle for multicomponent catalysts with coordinated hydrogen dynamics.