Visible or Near-infrared Light Self-powered Photodetectors Based on Transparent Ferroelectric Ceramics.

Transparent ferroelectrics, with promising prospect in transparent optoelectronic devices, have unique advantages in self-powered photodetection. The self-powered photodetectors based on photovoltaic effect have quicker response and higher stability compared with those based on pyroelectric effect. However, the ferroelectric ceramics previously applied are always opaque and have no infrared light stimulated photovoltaic effect. Thus, it would be very meaningful to design photodetectors based on infrared light stimulated photovoltaic effect or/and transparent ferroelectric ceramics. In this work, highly optical transparent pristine PLZT and bandgap engineered Ni doped PLZT ceramics with excellent piezoelectric/ferroelectric properties were prepared by hot-pressing sintering. Stable and excellent photovoltaic performance was obtained for pristine PLZT and bandgap engineered PLZT. The value of short-circuit current density is at least two orders of magnitude larger than those in PLZT reported in previous works. The transparent PLZT and Ni doped PLZT ferroelectric ceramics are applied as self-powered photodetectors for the first time for 405 nm and near infrared light, respectively. The devices based on PLZT under 405 nm light exhibit high detectivity (7.15×107 Jones) and quick response (9.5 ms for rise and 11.5 ms for decay), and those devices based on Ni doped PLZT, under near infrared light filtered from AM 1.5 G simulated sunlight, also exhibit high detectivity (6.86×107 Jones) and short response time (8.5 ms), both presenting great potential for future transparent photodetectors.