Enhanced photoconductivity performance of microrod-based Sb2Se3 device

Antimony selenide is a potential material among 2D materials for photovoltaic applications due to its broad absorption range from visible to NIR. In thin-film photodetector, the formation of Sb2O3 limits the device's photocurrent and low bias operation. This work compares a Sb2Se3 microrod-based device and a thin film-based device. Because of the lower bandgap than the film-based Sb2Se3, the microrod-based device showed a broadband photoresponse in near-IR and visible regions. The photocurrent was measured at 1064 nm wavelength with variable power for the microrod-based device. The device offered a responsitivity of 0.036 mA/W and external quantum efficiency of 42 % at 1064 nm and 12 mW/cm2 power density. Also, the photocurrent increased from nano-Amps to the micro-Amps for the rod. Given the high response and low bias operation, the present device paves a path for a new device with a simple processing method.