| 초록 |
Halide perovskites are promising material for thin film photovoltaic applications due to their high absorption coefficient in visible wavelength region, low exciton binding energies, and long diffusion lengths of photo-generated electrons and holes within perovskite films. Also, they can produce very narrow FWHM of photo/electroluminescence spectrum (~ 20nm), which makes also promising in light-emitting applications such as LEDs, and lasers. [1] But, for commercialization, lead-containing issue on perovskite materials need to be considered. Here in, we synthesized lead-free, bismuth and antimony based A3B2X9 nancorystals (A = Cs, B = Bi, Sb, X = Br) using Ligand mediated re-precipitation method. Noticeably, by adding HBr additives into precursor solutions in the synthesis step, the PL intensities as well as PLQY (Photoluminescence quantum yield) of nanocrystals gradually increased. With optimization of synthesis protocol, we obtained high PLQY of 29 % with PL FWHM of 70 nm (PL peak position = 390 nm). Detailed experiments, and analysis will be presented. |
