A Stable Perovskite Sensitized Photonic Crystal P−N Junction with Enhanced Photoelectrochemical Hydrogen Production

The slow photon effect in inverse opal photonic crystals represents a promising approach to manipulate the interactions between light and matter through the design of material structures. This study introduces a novel ordered inverse opal photonic crystal (IOPC) sensitized with perovskite quantum dots (PQDs), demonstrating its efficacy for efficient visible‐light‐driven H 2 generation via water splitting. The rational structural design contributes to enhanced light harvesting. The sensitization of the IOPC with PQDs improves optical response performance and enhances photocatalytic H 2 generation under visible light irradiation compared to the IOPC alone. The designed photoanode exhibits a photocurrent density of 3.42 mA cm −2 at 1.23 V vs RHE. This work advances the rational design of visible light‐responsive photocatalytic heterostructure materials based on wide band gap metal oxides for photoelectrochemical applications.