Oriented growth and enhanced photocurrent of Fe doped centimeter-size long CsPbBr ₃ single crystal

Abstract Metal halide perovskites have demonstrated potential in light-emitting diodes, solar cells, and photodetectors due to their outstanding ionic and carrier properties. Elemental doping is considered an effective strategy for optimizing optoelectronic performance. This study reports high-quality CsPbBr ₃ single crystals, up to a centimeter in length, obtained via an antisolvent method. The crystal size, ranging from nanometers to micrometers, is measured by dynamic light scattering. We investigated the doped crystal structure, morphology, and optoelectronic properties. The Fe-doped crystal shows enhanced photocurrent and stability. At low doping (2%), it significantly enhances crystal quality and optoelectronic response: the photocurrent and responsivity of the doped crystal increase substantially under ultraviolet light. The photocurrent increased from 0.06 μ A to 1.2 μ A, showing at least one order of enhancement over that of the undoped. The responsivity rose to 6.05 mA W ⁻¹ , while the resistivity decreased to 1.1*10 ⁵ Ω cm. These crystals exhibited excellent stability and reproducibility during multiple on/off switching tests.