TY - JOUR
T1 - Highly efficient polymer solar cells based on low-temperature processed ZnO: application of a bifunctional Au@CNTs nanocomposite
AU - Li, Chang
AU - Wang, Ge
AU - Gao, Yajun
AU - Wang, Chen
AU - Wen, Shanpeng
AU - Li, Huayang
AU - Wu, Jiaxin
AU - Shen, Liang
AU - Guo, Wenbin
AU - Ruan, Shengping
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This study was supported by the International Cooperation and Exchange Project of Jilin Province (20170414002GH, 20180414001GH), the National Natural Science Foundation of China (Grant No. 15 11574110), the Project of Science and Technology Development Plan of Jilin Province (Grant 16 No. Grant No. 201602041013GX, 20180414020GH), the Project of Jilin Provincial 17 Development and Reform Commission (2018C040-2), Opened Fund of the State Key Laboratory on Applied Optics, and the China Postdoctoral Science Foundation (Grant No. 2014T70288, 2 2013M541299).
PY - 2019
Y1 - 2019
N2 - Although ZnO electron transport layers (ETL) contribute to the world record for single-junction polymer solar cells, its sintering temperature, which is higher than 200 °C, imposes limits on the application of low-cost flexible devices. In this study, we report a modified low-temperature processed ZnO ETL by incorporating a composited nanostructure (Au@CNTs). Compared to the doping-free ZnO, the introduction of Au@CNTs improves the device performance in various aspects, through the initial charge generation until the following dissociation and transport processes. Furthermore, visible light soaking of the cells triggers the electric trap filling effect within the ZnO matrix, enabling the ZnO ETL to perform better in the electron extraction and transport and then reduces the interfacial recombination rate. Photoluminescence spectra together with Kelvin probes indicate that the visible light arouses a hot charge injection from Au nanoparticles (on CNTs) into ZnO, which populates the ZnO trap states and is responsible for the observed performance enhancement. As a result, a promising power conversion efficiency of 10.67% was achieved based on a state-of-the-art PTB7-Th:PC71BM photoactive system. Thus, we demonstrate that Au@CNTs nanocomposites have the potential to contribute toward promising ETL design for efficient polymer solar cells.
AB - Although ZnO electron transport layers (ETL) contribute to the world record for single-junction polymer solar cells, its sintering temperature, which is higher than 200 °C, imposes limits on the application of low-cost flexible devices. In this study, we report a modified low-temperature processed ZnO ETL by incorporating a composited nanostructure (Au@CNTs). Compared to the doping-free ZnO, the introduction of Au@CNTs improves the device performance in various aspects, through the initial charge generation until the following dissociation and transport processes. Furthermore, visible light soaking of the cells triggers the electric trap filling effect within the ZnO matrix, enabling the ZnO ETL to perform better in the electron extraction and transport and then reduces the interfacial recombination rate. Photoluminescence spectra together with Kelvin probes indicate that the visible light arouses a hot charge injection from Au nanoparticles (on CNTs) into ZnO, which populates the ZnO trap states and is responsible for the observed performance enhancement. As a result, a promising power conversion efficiency of 10.67% was achieved based on a state-of-the-art PTB7-Th:PC71BM photoactive system. Thus, we demonstrate that Au@CNTs nanocomposites have the potential to contribute toward promising ETL design for efficient polymer solar cells.
UR - http://hdl.handle.net/10754/652970
UR - https://pubs.rsc.org/en/Content/ArticleLanding/2019/TC/C8TC05653F#!divAbstract
UR - http://www.scopus.com/inward/record.url?scp=85062352945&partnerID=8YFLogxK
U2 - 10.1039/c8tc05653f
DO - 10.1039/c8tc05653f
M3 - Article
SN - 2050-7526
VL - 7
SP - 2676
EP - 2685
JO - Journal of Materials Chemistry C
JF - Journal of Materials Chemistry C
IS - 9
ER -