Hydrogen peroxide (H2O2) is an important chemical commodity. Currently, the anthraquinone auto-oxidation (AO) process is the dominant method for producing hydrogen peroxide worldwide. However, alternative generation methods are being extensively investigated, most notably photocatalytic H2O2 synthesis. State-of-the-art heterogeneous photocatalysts can now produce H2O2 from water and O2 with apparent quantum yields (AQYs) of approximately 20% at 420 nm and solar-to-chemical conversion (SCC) efficiencies of several percent. Unlike electrochemical and other emerging methods, photocatalysis can, in principle, deliver H2O2 of high purity, i.e., H2O2 aqueous solution that is free of electrolytes and other foreign species. However, in the efforts of optimizing the structure of photocatalysts and achieving higher AQY, SCC and the yield rate of H2O2 (mol[H2O2] g−1[photocatalyst] h−1), the community appears to drift away from another key performing indicator (KPI), which is exceptionally important to make photocatalysis competitive not only to other emerging methods, but also the AO process. This KPI is concentration of H2O2 achieved in photocatalysis. This quantity is still in the range of few millimoles per litter (mM). In this opinion article, we articulate importance of this KPI and the viable, in our opinion, strategies of increasing this value by means of heterogeneous photocatalysis.
- Open Access
- Opinion
Defining Key Performing Indicators for Economically Feasible H2O2 Production by Means of Photocatalysis
Author Information
Received: 03 Mar 2026 | Revised: 21 Apr 2026 | Accepted: 29 Apr 2026 | Published: 07 May 2026
Abstract
Keywords
hydrogen peroxide | photocatalysis | solar-to-chemical conversion efficiency | quantum yield | concentration | heterogeneous catalysis
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