Anion–cation synergistic doping strategy on a Ga2O3 scaffold for improving electron extraction and transport in a CH3NH3PbCl3-based photodetector

Abstract

Efficient electron extraction and transport are crucial for high-performance perovskite devices. Herein, an anion–cation synergistic doping strategy is adopted on the electron transport layer of the CH₃NH₃PbCl₃-based photodetector. The cation Zn²⁺ doping decreases the oxygen vacancies and suppresses carrier recombination. In the meantime, the anion CH₃COO⁻ doping controls the longitudinal dimension and accelerates electron transport. On this basis, the comprehensive performances of the photodetector are significantly improved. Impressively, the device responds rapidly to the UVA waveband with a peak responsivity of 70.57 mA W⁻¹ and a switching ratio exceeding 10⁴ in self-powered mode. In contrast, the corresponding values are only 8.02 mA W⁻¹ and 870 in the pristine device, respectively. Moreover, the peak detectivity is up to 1.21 × 10¹² Jones under zero bias. Benefiting from these encouraging properties, the photodetector reveals excellent imaging capacity and a high-resolution optical image has been achieved. These results demonstrate that anion–cation synergistic doping is a simple but effective strategy to improve the electron extraction and transport in perovskite devices.