Self-Powered High-Responsivity Photodetectors Enhanced by the Pyro-Phototronic Effect Based on a BaTiO3/GaN Heterojunction.

Perovskite and semiconductor materials are always the focus of research because of their excellent properties, including pyroelectric, photovoltaic effects, and high light absorption. On basis of this, the design of combining BaTiO3 (BTO) thin films with a GaN layer to form a heterojunction structure with a pyro-phototronic effect has achieved an efficient self-powered BTO/GaN ultraviolet photodetector (PD) with high responsivity and a fast response speed. With cooling and prepolarization treatments, the photocurrent peak and plateau have been enhanced by up to 1348 and 1052%, and the response time of the pyroelectric and common photoelectric current are improved from 0.35 to 0.16 s and from 3.27 to 2.35 s with a bias applied, respectively. The self-powered BTO/GaN PD combined with a pyro-phototronic effect provides a new idea and optimization for realizing ultrafast ultraviolet sensing at room temperature, making it a promising candidate in environmentally friendly and economical ultraviolet optoelectronic devices.