Enhancement of CsPbBr3 Perovskite Single-Crystal Photodetector Performance via Zr Ion Implantation

All-inorganic halide perovskite single crystals haveattractedsignificant attention in optoelectronic fields on account of theiroutstanding optoelectronic properties. Photodetectors (PDs) basedon CsPbBr3 single crystal exhibit high responsivity (R) and external quantum efficiency (EQE) due to the directoptical band gap, large optical absorption throughout the visiblespectrum range, and long-term stability. Herein, we prepared the centimeter-sizeCsPbBr(3) perovskite single crystal and utilized Zr ion implantationto modify the photoelectric properties of single crystals. The opticalband gap of the CsPbBr3 single crystal decreases from 2.24to 2.12 eV, and the absorption intensity increases after Zr ion implantation.The R and EQE of the CsPbBr3 single crystalphotodetector modified by Zr ion implantation are 1.0 A W-1 and 294%, respectively, with a light intensity of 3.8 mW cm(-2) and a 5 V bias under 425 nm illumination, which areten times larger than that of the pristine devices. Meanwhile, thefirst-principles calculation results show that the introduction ofZr ions decreases the band gap and that the Zr 4d orbit contributesto the conduction band minimum (CBM), which facilitates carrier transportin Zr ion implanted CsPbBr3 single crystals. The resultsshow that Zr ion implantation is an effective strategy to improvethe performance of the CsPbBr3 single-crystal-based PDs.