TY - JOUR
T1 - Pinning Down the Anomalous Light Soaking Effect toward High-Performance and Fast-Response Perovskite Solar Cells
T2 - The Ion-Migration-Induced Charge Accumulation
AU - Zhang, Teng
AU - CHEUNG, Sin Hang
AU - Meng, Xiangyue
AU - Zhu, Lei
AU - Bai, Yang
AU - Ho, Carr Hoi Yi
AU - Xiao, Shuang
AU - Xue, Qingzhong
AU - SO, Shu Kong
AU - Yang, Shihe
N1 - Funding Information:
This work was supported by HK-RGC General Research Funds (GRF Nos. 16312216 and 16300915), the HK Innovation and Technology Fund (ITS/219/16), and the Shenzhen Peacock Plan (2016).
PY - 2017/10/19
Y1 - 2017/10/19
N2 - The light soaking effect (LSE) is widely known in perovskite solar cells (PVSCs), but its origin is still elusive. In this study, we show that in common with hysteresis, the LSE is owed to the ion migration in PVSCs. Driven by the photovoltage, the mobile ions in the perovskite materials (MA+/I-) migrate to the selective contacts, forming a boosted P-i-N junction resulting in enhanced charge separation. Besides, the mobile ions (MA+) can soften and suture the PCBM/perovskite interface and thus reduce the trap density, in keeping with a higher open-circuit voltage. Finally, almost LSE-free PVSCs can be prepared by using 0.1 wt % MAI-doped PCBM as the electron transport material, whereas overdoping (1 wt % MAI doping) makes the LSE even more pronounced due to excess mobile ions that need time to migrate to reach a new quasi-static state.
AB - The light soaking effect (LSE) is widely known in perovskite solar cells (PVSCs), but its origin is still elusive. In this study, we show that in common with hysteresis, the LSE is owed to the ion migration in PVSCs. Driven by the photovoltage, the mobile ions in the perovskite materials (MA+/I-) migrate to the selective contacts, forming a boosted P-i-N junction resulting in enhanced charge separation. Besides, the mobile ions (MA+) can soften and suture the PCBM/perovskite interface and thus reduce the trap density, in keeping with a higher open-circuit voltage. Finally, almost LSE-free PVSCs can be prepared by using 0.1 wt % MAI-doped PCBM as the electron transport material, whereas overdoping (1 wt % MAI doping) makes the LSE even more pronounced due to excess mobile ions that need time to migrate to reach a new quasi-static state.
UR - http://www.scopus.com/inward/record.url?scp=85031811682&partnerID=8YFLogxK
U2 - 10.1021/acs.jpclett.7b02160
DO - 10.1021/acs.jpclett.7b02160
M3 - Journal article
AN - SCOPUS:85031811682
SN - 1948-7185
VL - 8
SP - 5069
EP - 5076
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 20
ER -
