| 초록 |
Perovskite solar cells based on methylammonium trihalide (CH3NH3PbI3 and CH3NH3PbI3-xClx) have recently emerged as promising materials. Especially, the mixed halide perovskite absorber (CH3NH3PbI3-xClx) generally shows a long electron-hole diffusion length over 1um while CH3NH3PbI3 has a relatively short electron-hole diffusion length ~100 nm. So, the ratio of chlorine in perovskite solar cells is a very critical parameter, but there are few systematic researches on it. Here, to control the ratio of chlorine, we prepared the mixed halide perovskite solar cells employing new two-step solution process. Although this two-step process doesn’t much change the ratio of chorine in perovskite absorber, we found that the slightly change of chlorine ratio obviously affected on the PCE. The quantitative composition, packing mode, and morphology of this mixed halide perovskite was confirmed by energy dispersive X-ray spectroscopy, X-ray diffraction, and scanning electron microscope, respectively. |
