Light‐Promoted Hydrazine Dehydrogenation over Ni/NH ₂ ‐MIL‐125: Unraveling Mechanisms for Efficient Hydrogen Production

Abstract Developing efficient, low‐cost, and durable catalysts for the complete dehydrogenation of hydrous hydrazine (N 2 H 4 ·H 2 O) remains a significant challenge. Herein, a high‐performance, visible‐light‐responsive Ni‐loaded amino‐functionalized MIL‐125 (Ni/NH 2 ‐MIL‐125) catalyst is fabricated via a facile chemical reduction method, which, for the first time, enables visible‐light‐enhanced N 2 H 4 dehydrogenation using a non‐precious metal catalyst. Under visible light irradiation, Ni/NH 2 ‐MIL‐125 achieves a turnover frequency (TOF) of 220.2 h −1 at 323 K, more than twice that in the dark (108.1 h −1 ) and outperforms most reported non‐precious metal catalysts. Characterizations and theoretical calculations reveal that the enhanced light‐promoted activity arises from light‐induced electron transfer from the NH 2 ‐MIL‐125 to the Ni active sites, which synergistically strengthens N 2 H 4 adsorption and lowers the energy barrier for N─H bond cleavage, the rate‐determining step. This work establishes visible‐light promotion as a powerful strategy to enhance non‐precious metal catalysis and offers a promising avenue for nitrogen‐based hydrogen storage systems.