유기-무기물 첨가제 도입을 통하여 표면 결함이 제어된 고성능 페로브스카이트 나노결정 발광 다이오드 연구

Abstract

Halide perovskite nanocrystals (PNCs) demonstrate exceptional characteristics such as remarkable color purity, adjustability of emission wavelength, and a high photoluminescence quantum yield (PLQY). The efficiency and stability of perovskite light emitting diodes (LED) are influenced by the PLQY of the emitting layer and the density of traps. Thus, it is crucial to enhance the radiative recombination process through the reduction of surface defects in PNCs. In this thesis, I explored the utilization of cadmium acetate (CdAc) treatments with organic ligand engineering to passivate surface defects in PNCs. Our findings also indicate that the incorporation of cadmium ions can effectively reduce the formation energy of defects in PNCs via CdAc treatment. The results demonstrate that the implementation of CdAc treatment resulted in a decrease in the non-radiative recombination and defect density of PNCs. The optimized CdAc treated PNCs exhibited an enhanced PLQY of 96.02% in the green region (514 nm), as well as an efficient external quantum efficiency (EQE) of 20.79% when utilized in LED devices.