Department of Chemistry and Center for NanoScience (CeNS) , LMU Munich , Butenandtstrasse 5-13 , 81377 München , Germany.
Experimental Physics VI , Julius Maximilian University of Würzburg , 97074 Würzburg , Germany.
ACS Appl Mater Interfaces. 2018 Apr 11;10(14):11414-11419. doi: 10.1021/acsami.8b00990. Epub 2018 Mar 28.
We tune the Fermi level alignment between the SnO electron transport layer (ETL) and Cs(FAMA)Pb(IBr) and highlight that this parameter is interlinked with current-voltage hysteresis in perovskite solar cells (PSCs). Furthermore, thermally stimulated current measurements reveal that the depth of trap states in the ETL or at the ETL-perovskite interface correlates with Fermi level positions, ultimately linking it to the energy difference between the Fermi level and conduction band minimum. In the presence of deep trap states, charge accumulation and recombination at the interface are promoted, affecting the charge collection efficiency adversely, which increases the hysteresis of PSCs.
我们调整了 SnO 电子传输层（ETL）和 Cs(FAMA)Pb(IBr)之间的费米能级排列，并强调了这一参数与钙钛矿太阳能电池（PSC）中的电流-电压滞后有关。此外，热刺激电流测量表明，在 ETL 或 ETL-钙钛矿界面处的陷阱态深度与费米能级位置相关，最终将其与费米能级和导带最小值之间的能量差联系起来。在深陷阱态存在的情况下，界面处的电荷积累和复合会得到促进，从而对电荷收集效率产生不利影响，这会增加 PSC 的滞后现象。
