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. Photocatalytic water splitting produces clean H2 gas by converting light to chemical energy. In this Primer, Nishioka et al. describe reliable methods for conducting experiments and the proper characterization and evaluation techniques to improve reproducibility in this field.