@article {12502,
	title = {Direct Observation of Long Electron-Hole Diffusion Distance in CH3NH3PbI3 Perovskite Thin Film},
	journal = {Sci RepSci RepSci Rep},
	volume = {5},
	year = {2015},
	note = {Li, YuYan, WeiboLi, YunlongWang, ShufengWang, WeiBian, ZuqiangXiao, LixinGong, QihuangengEngland2015/09/30 06:00Sci Rep. 2015 Sep 29;5:14485. doi: 10.1038/srep14485.},
	pages = {14485},
	abstract = {In high performance perovskite based solar cells, CH3NH3PbI3 is the key material. We carried out a study on charge diffusion in spin-coated CH3NH3PbI3 perovskite thin film by transient fluorescent spectroscopy. A thickness-dependent fluorescent lifetime was found. By coating the film with an electron or hole transfer layer, [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) or 2,2{\textquoteright},7,7{\textquoteright}-tetrakis(N,N-di-p-methoxyphenylamine)-9,9{\textquoteright}-spirobifluorene (Spiro-OMeTAD) respectively, we observed the charge transfer directly through the fluorescence quenching. One-dimensional diffusion model was applied to obtain long charge diffusion distances in thick films, which is ~1.7 mum for electrons and up to ~6.3 mum for holes. Short diffusion distance of few hundreds of nanosecond was also observed in thin films. This thickness dependent charge diffusion explained the formerly reported short charge diffusion distance (~100 nm) in films and resolved its confliction to thick working layer (300-500 nm) in real devices. This study presents direct support to the high performance perovskite solar cells and will benefit the devices{\textquoteright} design.},
	isbn = {2045-2322 (Electronic)2045-2322 (Linking)},
	author = {Y. Li and Yan, W. and Y. Li and S. Wang and Wang, W. and Bian, Z. and L. Xiao and Gong, Q.}
}
