| 초록 |
Perovskite solar cells based on methylammonium halide (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 1 μm while CH3NH3PbI3 has a relatively short electron-hole diffusion length ~100 nm. So, the ratio of chloride in perovskite solar cells is a very critical parameter, but there are few systematic researches on it. Here, to control the ratio of chloride, we prepared the mixed halide perovskite solar cells employing new two-step solution process. Although this two-step process does not much change the ratio of chloride in perovskite absorber, we found that the slightly change of chloride ratio obviously affected on the power conversion efficiency (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. |
