No abstract

Photovoltaic performances of CsPbI 2 Br solar cells are still lower than those of hybrid inorganic–organic perovskite solar cells, and researchers are exploring ways to improve their efficiencies. Due to its higher thermal stability in comparison with the generally studied hybrid inorganic–organic perovskites, all-inorganic CsPbI 2 Br has recently attracted great attention. By utilizing the combination of MnCl 2 and ZnCl 2 particles doping to modulate film growth, it is found that MnCl 2 and ZnCl 2 particles infiltrate into the holes of the CsPbI 2 Br lattice through the growth procedure, leading to suppressed nucleation and reduced growth rate. The combination assists to achieve higher CsPbI 2 Br crystalline grains for increased J sc as high as 15.66 mA cm −2 and FF as large as 73.37%. It is indicated that a specific combination of ZnCl 2 -MnCl 2 doping can fundamentally improve the film surface morphology, reduce trap density, and suppress the recombination of carriers. Consequently, power conversion efficiency (PCE) is significantly improved from 13.47 to 14.15% compared with the reference device without doping.

Due to their outstanding performance, low cost, ease of fabrication, diverse photonic, and optoelectronic applications, metal halides perovskite have attracted extensive interest in photodetector applications. Currently, devices made by metal oxides, metal sulfides, and 2D materials had achieved good responsivity, but suffered from high dark current, slow response speed, small on-off ratio, and poor stability. Whole performances of these photodetectors are not satisfactory. Here, a lateral perovskite (CH3NH3PbBr3)/Ethanolamine/TiO2 (in ethanol) trilayer photodetector is designed for achieving high performance. EA treatment enhances electron extraction and reduces undesired recombination. This trilayer device shows good performances with low dark current of 1.5 × 10−11 A, high on-off ratio of 2700, high photodetectivity of 1.51 × 1012 Jones, high responsivity of 0.13 A W−1, and high stability, comparative to conventional single layer devices. This work provides the way to improve the performance of metal halide perovskite photodetectors.