Selective, Stable, Bias‐Free, and Efficient Solar Hydrogen Peroxide Production on Inorganic Layered Materials

Abstract

Abstract The importance of hydrogen peroxide (H 2 O 2 ) continues to grow globally. Deriving the oxygen reduction reaction (ORR) toward the 2e – pathway to form H 2 O 2 is crucial for high H 2 O 2 productivity. However, most selective electrocatalysts following the 2e – pathway comprise carbon‐containing organic materials with intrinsically low stability, thereby limiting their commercial applicability. Herein, layered double hydroxides (LDHs) are used as inorganic matrices for the first time. The LDH catalyst developed herein exhibits near‐100% 2e – ORR selectivity and stably produces H 2 O 2 with a concentration of ≈108.2 mm cm –2 photoanode in 24 h in a two‐compartment system (with a photoanode) with a solar‐to‐chemical conversion efficiency of ≈3.24%, the highest among all reported systems. Density functional theory calculations show that 2e – ORR selectivity is promoted by atomically dispersed cobalt atoms in (012) planes of the LDH catalyst, while a free energy gap between the * O and OOH – states is an important factor.