An Electrocatalytic/Heterogeneous Catalytic Cascade for Selective Production of Propylene Oxide via Anodic H 2 O 2 Generation

Abstract Propylene oxide, a key intermediate with wide applications in the plastics industry, is still mainly produced by energy‐intensive and environmentally non‐sustainable processes. Electrochemically assisted epoxidation of propylene is emerging as a sustainable and atom‐efficient method for highly selective synthesis of propylene oxide. Here, we introduce a cascade strategy that combines anodic H 2 O 2 generation with propylene epoxidation at a porous layer of immobilized titanium silicate (TS‐1). A ZnWO 4 electrocatalyst was developed for efficient anodic H 2 O 2 generation. To maximize local reactant concentrations, we designed an integrated TS‐1‐immobilized gas diffusion layer, which facilitates rapid propylene transport to the triple‐phase boundaries, while preventing TS‐1 loss and avoiding separation issues common in solution‐phase heterogeneous catalytic systems. Furthermore, an acetonitrile‐bicarbonate containing electrolyte system was optimized to facilitate direct utilization of H 2 O 2 for propylene epoxidation, leading to 98% H 2 O 2 utilization efficiency and over 97% selectivity for propylene oxide. This work offers a safer and greener alternative for propylene oxide production and broadens the application of electrochemically generated H 2 O 2 from water oxidation for selective oxygenation reactions.