Abstract

Recent advances in the field of integrated solar hydrogen technologies are presented. Economic, technical, and practical aspects are discussed, pinpointing the major current bottlenecks for solar hydrogen devices to reach the market. Solar hydrogen devices have the potential to reach high solar‐to‐hydrogen conversion efficiencies, to be produced at low cost and have promising durability. Major research challenges remain to reach that target. This overview departs from considerations at macroscale and discusses the features of individual components of devices at the different length scales down to nanoscale. For the device itself as well as for each of its components, perspectives for improvement are presented.