Optimizing Optoelectronic Performances by Controlling Halide Compositions for MAPb(ClxI1-x)3 Single Crystals
This article aims at investigating the structures of iodide/chloride mixed-halide perovskites and correlating the I: Cl ratio with their optoelectronic performances. A series of 8 MAPb(ClxI1-x)3 (x=0, 0.01, 0.04, 0.05, 0.06, 0.20, 0.99, 1) single crystals were successfully grown. The crystals with different doping concentrations showed different optical-absorption and PL emission. The band gaps were successfully tuned from 1.46 to 2.92 eV. The photodetectors were designed using 8 crystals, among which the MAPb(Cl0.2I0.8)3 single crystal exhibits superior photocurrent to dark current ratio (Ilight/Idark ratio of 1547 when the incident light is ~1609μW/cm2, 546nm). This detailed investigation on Cl/I mixed halide lead methylammonium perovskites is important for optimizing device performances through composition tuning.