Low-temperature-processed ZnO thin films as electron transporting layer to achieve stable perovskite solar cells
- 181 Downloads
Morphology and surface property of ZnO thin films as electron transporting layer in perovskite solar cells are crucial for obtaining high-efficient and stable perovskite solar cells. In this work, two different preparation methods of ZnO thin films were carried out and the photovoltaic performances of the subsequent perovskite solar cells were investigated. ZnO thin film prepared by sol–gel method was homogenous but provided high series resistance in solar cells, leading to low short circuit current density. Lower series resistance of solar cell was obtained from homogeneous ZnO thin film from spin-coating of colloidal ZnO nanoparticles (synthesized by hydrolysis–condensation) in a mixture of 1-butanol, chloroform and methanol. The perovskite solar cells using this film achieved the highest power conversion efficiency (PCE) of 4.79% when poly(3-hexylthiophene) was used as a hole transporting layer. In addition, the stability of perovskite solar cells was also examined by measuring the photovoltaic characteristic for six consecutive weeks with the interval of 2 weeks. It was found that using double layers of the sol–gel ZnO and ZnO nanoparticles provided better stability with no degradation of PCE in 10 weeks. Therefore, this work provides a simple method for preparing homogeneous ZnO thin films in order to achieve stable perovskite solar cells, also for controlling their surface properties which help better understand the characteristics of perovskite solar cells.
KeywordsPerovskite solar cells ZnO thin film Stable Sol–gel Nanoparticles
This research was financially supported by Chiang Mai University and the Development and Promotion of Science and Technology Talents Project (DPST) (Research Fund for DPST Graduate with First Placement No. 25/2557). The authors thank Dr. Chawalit Bhoomanee for help in the device preparation and measurement. The authors would like to acknowledge the scholarship from School of Renewable Energy, Maejo University, and the Energy Policy and Planning Office, Ministry of Energy, Thailand.
This research was financially supported by Chiang Mai University and the Development and Promotion of Science and Technology Talents Project (DPST) (Research Fund for DPST Graduate with First Placement No. 25/2557). This work was also supported by National Research Council of Thailand.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Idigoras, J., Todinova, A., Sanchez-Valencia, J.R., Barranco, A., Borras, A., Anta, J.A.: The interaction between hybrid organic–inorganic halide perovskite and selective contacts in perovskite solar cells: an infrared spectroscopy study. Phys. Chem. Chem. Phys. 18, 13583–13590 (2016)CrossRefGoogle Scholar
- Kim, H.-S., Lee, C.-R., Im, J.-H., Lee, K.-B., Moehl, T., Marchioro, A., Moon, S.-J., Humphry-Baker, R., Yum, J.-H., Moser, J.E., Grätzel, M., Park, N.-G.: Lead iodide perovskite sensitized all-solid-state submicron thin film mesoscopic solar cell with efficiency exceeding 9%. Sci. Rep. (2012). https://doi.org/10.1038/srep00591 CrossRefGoogle Scholar
- Mahmud, M.A., Elumalai, N.K., Upama, M.B., Wang, D., Puthen-Veettil, B., Haque, F., Wright, M., Xu, C., Pivrikas, A., Uddin, A.: Controlled Ostwald ripening mediated grain growth for smooth perovskite morphology and enhanced device performance. Sol. Energy Mater. Sol. Cells 167, 87–101 (2017)CrossRefGoogle Scholar
- Mallick, P.: Effect of solvent on the microstructure and optical band gap of ZnO nanoparticles. Nanoelectron. Mater. Dev. 55, 187–192 (2017)Google Scholar
- Ruankham, P., Wongratanaphisan, D., Gardchareon, A., Phadungdhitidhada, S., Choopun, S., Sagawa, T.: Full coverage of perovskite layer onto ZnO nanorods via a modified sequential two-step deposition method for efficiency enhancement in perovskite solar cells. Appl. Surf. Sci. 410, 393–400 (2017)ADSCrossRefGoogle Scholar
- Shen, K., Sun, H.L., Ji, G., Yang, Y., Jiang, Z., Song, F.: Fabrication and characterization of organic–inorganic hybrid perovskite devices with external doping. Nanoelectron. Mater. Dev. Chapter 6, 95–116 (2016)Google Scholar
- Shibayama, N., Kanda, H., Yusa, S., Fukumoto, S., Baranwal, A.K., Segawa, H., Miyasaka, T., Ito, S.: All-inorganic inverse perovskite solar cells using zinc oxide nanocolloids on spin coated perovskite layer. Nano Converg. 4(18), 1–5 (2017)Google Scholar
- Ye, M., Liu, X., Iocozzia, J., Liu, X., Lin, Z.: Nanostructured materials for high efficiency perovskite solar cells. In: Li, Q. (ed.) Nanomaterials for Sustainable Energy, NanoScience and Technology, pp. 1–39. Springer, Cham (2016)Google Scholar
- Zhao, Y.H., Zhang, K.C., Wang, Z.W., Huang, P., Zhu, K., Li, Z.D., Li, D.H., Yuan, L.G., Zhou, Y., Song, B.: Comprehensive study of sol − gel versus hydrolysis–condensation methods to prepare ZnO films: electron transport layers in perovskite solar cells. ACS Appl. Mater. Interfaces. 9(31), 26234–26241 (2017)CrossRefGoogle Scholar