Progress in photocapacitors: a review

In recent years, there has been a gradual increase in the development and research of photocapacitors as integrated devices, which hold the potential to address the intermittent output problem of solar cells. However, the overall efficiency of existing photocapacitors is much lower than that of the photovoltaic devices they employ, greatly limiting their usability. As photocapacitors are at the intersection of photovoltaic devices and supercapacitors, the development of these devices is still in its initial stage, and the related research is faced with numerous challenges. This review provides a constructive introduction to the classification of photocapacitors and briefly outlines the development process. Finally, the problems of photocapacitors that need to be solved are pointed out.