“Quantum dot light-emitting diodes (QLEDs) are an important development direction for the new generation of display technology, and their electron transport layer (ETL) usually uses zinc oxide (ZnO) material. However, the high electron mobility of ZnO can easily lead to carrier injection imbalance in the emissive layer (EML), and surface defects such as oxygen vacancies can cause non radiative recombination. This study innovatively introduces hexagonal boron nitride (h-BN), a typical two-dimensional material, to construct an electron barrier layer between EML and ZnO interface. The experimental results show that the introduction of h-BN effectively improves the internal carrier balance of the device and significantly suppresses the luminescence quenching caused by ZnO defects. After h-BN interface modification, the external quantum efficiency (EQE) and current efficiency (CE) of QLED devices reached 17.31% and 18.80 cd/A, respectively, achieving an improvement of 12.4% and 7.43% compared to the reference device. This study not only reveals the innovative application value of two-dimensional materials in QLED devices, but also provides new research ideas for their in-depth development in the field of display technology.”