Enhanced photocurrent via ferro-pyro-phototronic effect in ferroelectric BaTiO₃ materials for a self-powered flexible photodetector system

Some ferroelectric materials have demonstrated both pyroelectric and photovoltaic effects for scavenging thermal and solar energies. However, how to couple pyroelectric and photovoltaic effects in ferroelectric materials remains a challenge. Here, a ferro-pyro-phototronic effect based on coupling pyroelectric and photovoltaic effects has been utilized to enhance the photocurrent in a ferroelectric BaTiO₃-based flexible photodetector system. As compared with a purely photovoltaic system, the corresponding current peak and plateau were 451.9% and 17.2% higher in the coupled photovoltaic-pyroelectric system, respectively. The results can be explained by ferro-pyro-phototronic effect with an induced energy band bending. As a demonstration of its potential application, we developed a sensing system that is suitable for detecting and recognizing both light and temperature variations by recording the electrical signals mapped as an array.