Ultrafast interfacial charge transfer regulation in organo-metal perovskites through bandgap engineering

Selecting suitable materials for electron transport layers and optimizing their electronic properties are crucial for enhancing the performance of organic light-emitting diode. However, the harsh deposition conditions and high costs associated with traditional charge transport layers indicate significant potential for further optimization. Herein, we investigate charge transfer at organic-perovskite heterojunctions and explore how bandgap engineering can be utilized to modulate interfacial charge dynamics. Using transient absorption and time-resolved photoluminescence spectroscopy, we demonstrate that charge transfer at the interface of organic-perovskite heterojunction can be regulated and enhanced by increasing the energy level offset, which is achieved through the adjustment of the halide ion ratio in the perovskite material. These findings provide insights into interfacial charge transfer mechanisms and confirm the feasibility of bandgap engineering as a strategy for tailoring charge-transfer properties in organic optoelectronic devices.