|
The performance of polymer/perovskite solar cells (PSCs/PVKSCs) is highly dependent on the interfacial contact between the active layer and electrodes. Water/alcohol soluble interfacial materials, which enable orthogonal processing of high-performance multi-layer PSCs can greatly improve the interfacial contact as well as device performance. Traditional interfacial materials are not compatible with the large-area processing of PSCs using roll-to-roll techniques. Here, we present a series of self-doped interfacial materials with controlled doping properties and high mobility for the interface optimization of PSCs. Self-doped interfacial materials containing n-type conjugated backbone and polar side chains are prepared. It was shown that neutral amino groups undergo photo-induced doping process while the bromide-quaternized groups employ a self-doped mechanism.1 Further study on the counterions of the self-doped interfacial materials shows that the counterions can also induce different self-assembling and doping behavior with different strength, leading to varied charge-transporting properties. 2 More importantly, these self-doped interfacial materials can enable high-performance (>10%) PSCs and still work efficiently in varied thickness, which match well with the requirement of the fabrication of large-area PSCs. Based on the development of self-doped interfacial materials, a high-performance interconnecting layer for tandem solar cells was also developed, which can boost the power conversion efficiency (PCE) of tandem solar cells to 11.35%.3 Moreover, these interfacial materials can passivate the surface traps of perovskite to improve the electron extraction properties of PVKSC, leading to high-performance PVKSCs even when the thickness of interfacial material is more than 200 nm.4 The successful development of self-doped interfacial materials offers a better processing window for potential fabrication of PSCs/PVKSCs using large-area processing method.
1 J. Am. Chem. Soc. 2016, 138, 2004-2013.
2 Mater. Horiz. 2017, 4, 88-97.
3 Adv. Mater. 2016, 28, 4817-4823.
4 Adv. Energy Mater. 2016, 1501534.
|
