Synergy of electron transfer and hydrogen spillover at Pd‐ <scp> SnO ₂ </scp> interface for efficient direct <scp> H ₂ O ₂ </scp> synthesis

Abstract Pd‐based catalysts often suffer from low H 2 O 2 selectivity and productivity due to O‐O bond cleavage. Herein, we address this challenge by constructing a well‐defined Pd‐SnO 2 interface on carbon nanotubes through a precisely controlled N 2 ‐thermal treatment. This key step ensures the reduction of Pd oxides while maintaining SnO 2 in an oxidized state, inducing moderate electron transfer from SnO 2 to Pd. The optimized Pd‐SnO 2 /CNTs catalyst exhibits outstanding H 2 O 2 productivity of 38,925 mol·kg Pd −1 ·h −1 , with 47.1% H 2 conversion and 52.7% H 2 O 2 selectivity, alongside excellent stability over five cycles. DFT simulations and experimental analysis reveal the Pd‐SnO 2 interface induces a moderate downshift in the d ‐band center of Pd, weakening the adsorption of reaction species on Pd 0 sites. A synergistic dual‐site mechanism occurs via H 2 dissociation and spilled‐over H* species on Pd 0 , while adjacent SnO 2 domains act as active sites for the sequential hydrogenation of activated O 2 , leading to the selective formation of H 2 O 2 .