Photocatalytic water splitting

With the goal of achieving large-scale H2 production from renewable resources, water splitting into H2 and O2 using semiconductor photocatalysts (sometimes called artificial photosynthesis) has been studied for five decades. Unfortunately, the lack of rigour and reproducibility in the data collection and analysis of experimental results has hindered progress in the field. This Primer provides a comprehensive overview of proper characterization and evaluation of photocatalysts for overall water splitting. In particular, the Primer covers various pitfalls in photocatalysis research, best practices for reproducibility and reliable methods for conducting rigorous experiments. The recommendations are intended to reduce false positives in the literature and to promote progress towards a practical technology for producing H2 from water by using sunlight.

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Acknowledgements

S.N. acknowledges support by a Grant-in-Aid for Research Activity Start-up (JP21K20555). F.E.O. acknowledges support from the US Department of Energy, Office of Science, Office of Basic Energy Sciences (Award Number DOE-SC0015329). X.W. acknowledges support from the National Natural Science Foundation of China (22032002 and U1905214). T.E.M. acknowledges support from the Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Energy Biosciences, Department of Energy (contract DE-SC0019781). K.M. acknowledges financial support by a Grant-in-Aid for Scientific Research (B) (JP22H01862), a Grant-in-Aid for Transformative Research Areas (A) “Supra-ceramics” (JP22H05148) and a Core-to-Core Program (JPJSCCA20200004) (JSPS).

Author information

Authors and Affiliations

  1. Department of Chemistry, School of Science, Tokyo Institute of Technology, Tokyo, Japan Shunta Nishioka & Kazuhiko Maeda
  2. Department of Chemistry, University of California, Davis, Davis, CA, USA Frank E. Osterloh
  3. State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, P. R. China Xinchen Wang
  4. Department of Chemistry, University of Pennsylvania, Philadelphia, PA, USA Thomas E. Mallouk
  5. International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, Japan Thomas E. Mallouk
  6. Living Systems Materialogy (LiSM) Research Group, International Research Frontiers Initiative (IRFI), Tokyo Institute of Technology, Yokohama, Kanagawa, Japan Kazuhiko Maeda
  1. Shunta Nishioka