@article{048683d40f7047469f0f45e07fd36a5b,
title = "Improved Performance of Carbon Electrode Perovskite Solar Cells Using Urea Treatment in Two-Step Processing",
abstract = "Perovskite solar cell has made a steady research progress with superior photovoltaic power conversion efficiency (PCE) over 25%. The quality of perovskite film is a key factor affecting device efficiency. Lewis bases such as urea, DMSO and thiourea etc. have been applied in perovskite precursor solutions for one step processing to effectively control the film morphology. Herein, we report urea treatment in a two-step processing for obtaining high quality methylammonium lead triiodide perovskite (CH3NH3PbI3) film, which is accomplished by immersing the PbI2 film into the mixture solution of urea/methylammonium iodide (MAI). The optimized urea concentration in the MAI solution is 0.4 mg/mL, leading to larger-sized and better crystalline perovskite grains than that without urea additive. The main function of the urea additive is the formation of the adduct MAI⋅PbI2⋅O=C(NH2)2, retarding the crystallization process of the perovskite film. The steady-state and time-resolved photoluminescence measurements revealed that perovskite CH3NH3PbI3 grown using optimized concentration of urea has prolonged carrier lifetime and reduced carrier recombination. Finally, the carbon-based perovskite solar cells fabricated from the optimal urea concentration of 0.4 mg/mL achieved the enhanced photovoltaic performance with the highest PCE of 13.10% and an average value of 11.34%, in comparison to devices without urea treatment exhibiting an average PCE of only 8.67%.",
keywords = "Lewis base additive, carbon-based perovskite solar cell, grain size, urea",
author = "Tingting Xu and Xuelin Sun and Weiwei Cao and Xiulan Qin and Ashim Gurung and Shaoshen Lv and Yonghua Chen and Lixin Chen and Wei Huang and Qiquan Qiao",
note = "Funding Information: The authors sincerely thank financial support from the National Natural Science Foundation of China (51972274, 51502246), China Postdoctoral Science Foundation (2019M653730), Natural Science Basis Research Plan in Shaanxi Province (2019JM-328), the Fundamental Research Funds for the Central Universities (310201911cx035). The Seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University (ZZ2019231, ZZ2019035). We would like to thank Dr. Zhou Yang from Shaanxi normal University for helping steady-state and time-resolved fluorescence measurement. We would like to thank the Analytical & Testing Center of NPU for the SEM and AFM measurements. This work has been supported by NSF MRI (1428992), NASA EPSCoR (NNX15AM83A), U.S. – Egypt Science and Technology (S&T) Joint Fund, SDBoR R&D Program and EDA University Center Program (ED18DEN3030025). This work is derived from the Subject Data supported in whole or part by NAS and USAID, and any opinions, findings, conclusions, or recommendations expressed in the paper are those of the authors alone, and do not necessarily reflect the views of USAID or NAS. Funding Information: The authors sincerely thank financial support from the National Natural Science Foundation of China (51972274, 51502246), China Postdoctoral Science Foundation (2019M653730), Natural Science Basis Research Plan in Shaanxi Province (2019JM‐328), the Fundamental Research Funds for the Central Universities (310201911cx035). The Seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University ( ZZ2019231, ZZ2019035). We would like to thank Dr. Zhou Yang from Shaanxi normal University for helping steady‐state and time‐resolved fluorescence measurement. We would like to thank the Analytical & Testing Center of NPU for the SEM and AFM measurements. This work has been supported by NSF MRI (1428992), NASA EPSCoR (NNX15AM83A), U.S. – Egypt Science and Technology (S&T) Joint Fund, SDBoR R&D Program and EDA University Center Program (ED18DEN3030025). This work is derived from the Subject Data supported in whole or part by NAS and USAID, and any opinions, findings, conclusions, or recommendations expressed in the paper are those of the authors alone, and do not necessarily reflect the views of USAID or NAS. Publisher Copyright: {\textcopyright} 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim",
year = "2020",
month = may,
day = "1",
doi = "10.1002/cnma.201900681",
language = "English (US)",
volume = "6",
pages = "806--815",
journal = "ChemNanoMat",
issn = "2199-692X",
publisher = "Wiley-VCH Verlag",
number = "5",
}