Defect density is one of the most significant characteristics of perovskite single crystals (PSCs) that determines their optical and electrical properties, but few strategies are available to tune this property. Here, we demonstrate that voltage regulation is an efficient method to tune defect density, as well as the optical and electrical properties of PSCs. A three-step carrier transport model of MAPbBr₃ PSCs is proposed to explore the defect regulation mechanism and carrier transport dynamics via an applied bias. Dynamic and steady-state photoluminescence measurements subsequently show that the surface defect density, average carrier lifetime, and photoluminescence intensity can be efficiently tuned by the applied bias. In particular, when the regulation voltage is 20 V (electrical poling intensity is 0.167 V μm⁻¹), the surface defect density of MAPbBr₃ PSCs is reduced by 24.27%, the carrier lifetime is prolonged by 32.04%, and the PL intensity is increased by 112.96%. Furthermore, a voltage-regulated MAPbBr₃ PSC memristor device shows an adjustable multiresistance, weak ion migration effect and greatly enhanced device stability. Voltage regulation is a promising engineering technique for developing advanced perovskite optoelectronic devices.

缺陷密度是钙钛矿单晶 (PSC) 最重要的特征之一，决定了它们的光学和电学特性，但很少有策略可以调整这种特性。在这里，我们证明了电压调节是调节缺陷密度以及 PSC 的光学和电学特性的有效方法。MAPbBr ₃的三步载流子输运模型PSC 被提议通过施加的偏置来探索缺陷调节机制和载流子传输动力学。随后的动态和稳态光致发光测量表明，表面缺陷密度、平均载流子寿命和光致发光强度可以通过施加的偏压进行有效调整。特别是当调节电压为20 V（电极化强度为0.167 V μm ^-1）时，MAPbBr ₃ PSCs的表面缺陷密度降低了24.27%，载流子寿命延长了32.04%，PL强度为增长了 112.96%。此外，电压调节的 MAPbBr ₃PSC忆阻器器件显示出可调多阻、弱离子迁移效应，大大增强了器件稳定性。电压调节是开发先进钙钛矿光电器件的有前途的工程技术。