Potential strategies such as surface passivation and perovskite material halide mixing may protect material surfaces, improve luminescence, and reduce charge traps for device stability. In this study, we used deep level transient spectroscopy to investigate the effect of CdSe/ZnS core-shell quantum dots (QDs) on defect states and carrier transport in methylammonium (MA) lead halide perovskites (CH₃NH₃PbX₃ where X = I, Br). In MAPbI₃ and MAPbI₂Br films with CdSe/ZnS QDs, the density of hole traps located at E_v + 0.37 eV and E_v + 0.56 eV was reduced dramatically. Deep traps at E_v + 0.78 eV and E_v + 1.08 eV were removed, and one broad electron trap signal dominated. Film photoresponsivity under 600-nm wavelength light and a bias voltage of −0.7 V was 10 and 18 mA/W, which is 100 and 27 times larger than the 0.1 and 0.67 mA/W of bare perovskites (PS), respectively. This demonstrates that carrier transport was enhanced due to defect suppression. Our findings on defect suppression and photoresponsivity enhancement provide an important direction for optimizing high-performance PS device fabrication.

诸如表面钝化和钙钛矿材料卤化物混合之类的潜在策略可以保护材料表面，改善发光并减少电荷陷阱，从而提高设备的稳定性。在这项研究中，我们使用深层瞬态光谱研究了CdSe / ZnS核壳量子点（QDs）对甲基铵（MA）卤化钙钛矿（CH ₃ NH ₃ PbX ₃，其中X = I，Br）。在具有CdSe / ZnS QD的MAPbI ₃和MAPbI ₂ Br薄膜中，位于E _v  + 0.37 eV和E _v  + 0.56 eV的空穴陷阱的密度大大降低。E _v  + 0.78 eV和E _v处的深陷阱 + 1.08 eV被去除，一个宽电子陷阱信号占主导地位。在600 nm波长的光和-0.7 V的偏置电压下，膜的光响应性分别为10和18 mA / W，分别是裸钙钛矿（PS）的0.1和0.67 mA / W的100和27倍。这表明由于缺陷抑制而提高了载流子传输。我们在缺陷抑制和光响应增强方面的发现为优化高性能PS器件制造提供了重要方向。