Electrochemical Reactors for Continuous Decentralized H2O2 Production

The global utilization of H2O2 is currently around 4 million tons per year and is expected to continue to increase in the future. H2O2 is mainly produced by the anthraquinone process, which involves multiple steps in terms of alkylanthraquinone hydrogenation/oxidation in organic solvents and liquid–liquid extraction of H2O2. The energy‐intensive and environmentally unfriendly anthraquinone process does not meet the requirements of sustainable and low‐carbon development. The electrocatalytic two‐electron (2 e−) oxygen reduction reaction (ORR) driven by renewable energy (e.g. solar and wind power) offers a more economical, low‐carbon, and greener route to produce H2O2. However, continuous and decentralized H2O2 electrosynthesis still poses many challenges. This Minireview first summarizes the development of devices for H2O2 electrosynthesis, and then introduces each component, the assembly process, and some optimization strategies. Electrochemical reactors for continuous decentralized H2O2 production are described in this Minireview, with separate discussions of flow field plates, catalyst layers, gas diffusion layers, membranes, shapes, and electrolyte compartments. The key factors of these parts and the optimization strategies for assembling flow cells are summarized. Insights and perspectives on key components are given.