Unveiling the Low‐Temperature Pseudodegradation of Photovoltaic Performance in Planar Perovskite Solar Cell by Optoelectronic Observation. Issue 18 (30th June 2016)

• Record Type: Journal Article
• Authors: Cao, Runan; Xu, Fei; Zhu, Jiabin; Ge, Sheng; Wang, Wenzhen; Xu, Haitao; Xu, Run; Wu, Yanglin; Ma, Zhongquan; Hong, Feng; Jiang, Zuimin
• Is Part Of: Advanced energy materials. Volume 6:Issue 18(2016)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2016-06-30
• Subjects: current–voltage characteristics -- ion migration -- perovskite solar cells -- quantum efficiency -- temperature dependence; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.201600814
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract : The time evolution of the current–voltage characteristic of planar heterojunction perovskite solar cell (PSC) is studied within an operating temperature range of 200–325 K. The photovoltaic (PV) performance of PSC is found to be influenced by five carrier transport pathways, which strongly depend on operating temperature and light illumination. At low temperature, a severe degradation of PV performance is presented but temporary. This is attributed to ion accumulation at the TiO2 /CH3 NH3 PbI3 and hole transport material/CH3 NH3 PbI3 interfacial regions, as an origin of screening effect of built‐in field, evidenced by the low external quantum efficiency (EQE). By light illumination at open‐circuit, a steady PV performance will be reached and the stabilization time increases with decreasing temperature. The recovery of PV performance is attributed to ion diffusion in CH3 NH3 PbI3 layer in the absence of electric field. The EQE observations indicate that photogenerated carriers are separated and collected efficiently after a long time light illumination due to a reduction of the screening effect. At high temperature, because of the low ion density at interfacial regions, the PV performance shows a quick response to light. These findings may help understanding of the mechanism of temperature‐dependent photogenerated carrier transport in the PSC. Abstract : The degradation of photovoltaic performance in perovskite solar cells is observed when the operating temperature goes down to 200 K. After light illumination at open‐circuit, the photovoltaic performance is significantly improved. A difference in carrier separation and collection efficiency is shown by external quantum efficiency measurement. This is attributed to the reduced screening effect of built‐in field.