Recent Progress of Methods to Enhance Photovoltaic Effect for Self‐Powered Heterojunction Photodetectors and Their Applications in Inorganic Low‐Dimensional Structures

An important class of photoelectronic devices, self‐powered photodetectors, has attracted worldwide attention because of its crucial role in both basic scientific research and commercial/public applications. Thanks to a special synergistic effect, excellent photoelectric properties, and outstanding mechanical stability, the study of heterojunction devices can provide valuable insights and new possibilities for the future of self‐powered photodetectors. This paper reviews the recent years of fundamental research of photovoltaic efficiency based on the ferroelectric‐enhanced photovoltaic effect, the pyro‐phototronic effect, and the piezo‐phototronic effect. It also highlights important topics related to heterojunctions and materials that are suitable for self‐powered photodetectors. The article concludes with an outlook of the future development in this important and rapidly advancing field. This review reports the recent progress in the fundamental investigations of self‐powered heterojunction photodetectors and highlights the five years of fundamental research of photovoltaic efficiency based on the ferroelectric‐enhanced photovoltaic effect, pyro‐phototronic effect, and piezo‐phototronic effect. This paper summarizes the application of these theories in metal oxide‐based heterojunctions, perovskite‐based heterojunctions, and sulfide‐based heterojunctions self‐powered photodetectors.