Recently, a collaborative research team led by Yang Yingguo and colleagues from Fudan University's School of Microelectronics, in conjunction with researchers such as Tang Aiwei from Beijing Jiaotong University, Lu Haizhou from Southeast University, and Ji Wenyu from Jilin University, has achieved a remarkable breakthrough in the study of the regulation and underlying mechanisms of the light-emitting interface in electroluminescent diodes (LEDs). Utilizing a 'one-step method', the team successfully constructed a three-dimensional/two-dimensional ordered heterojunction perovskite thin film. This innovation has significantly boosted the external quantum efficiency of green PeLEDs to an impressive 42.9% (with third-party certification confirming 42.3%), setting a new global benchmark. This strategy employs interface-induced crystallization to create a vertical gradient structure, effectively steering excitons away from defect-prone areas. As a result, the photoluminescence quantum efficiency has surged from 85% to 97%, while light extraction efficiency has reached 45.4%. Furthermore, the research shed light on the pivotal role of PEIE polymers in fostering the formation of ordered perovskite heterostructures, offering fresh insights for the design of high-performance LEDs. These significant findings have been published in the esteemed journal 'Nature'.