The Effects of CsBr Concentration on the Inorganic Cesium Lead Bromide Perovskite Film Properties and the Performances of Carbon-Based HTM-Free Perovskite Solar Cells

Main Article Content

Vallop Homrahad
Madsakorn Towannang
Pantiwa Kumlangwan
Wirat Jarernboon*
Samuk Pimanpang
Vittaya Amornkitbambung


Inorganic cesium lead bromide (ICLB) perovskite films were prepared onto an FTO conductive substrate by a two-step spin-dipping method. PbBr2 films were first coated onto the FTO substrate, and then they were immersed into CsBr solutions at various concentrations: 0.04, 0.06, 0.08, 0.10, and 0.12 M, forming the ICLB perovskite films. The surface morphology of the perovskite films prepared from the CsBr concentrations under 0.08 M had a uniform crystalline surface, but the CsBr concentrations above 0.08 M gave the film a non-uniform structure. XRD spectra of all ICLB films compose of mixed phases of monoclinic-CsPbBr3 and tetragonal-CsPb2Br5. The direct optical bandgap of 2.3 eV corresponded to the CsPbBr3 phase, and the indirect optical bandgap of 2.87-3.10 eV corresponded to the CsPb2Br5 phase. Carbon-based hole-transport-material (HTM) free CsPb2Br5 - CsPbBr3 perovskite solar cells were assembled, and the CsPb2Br5 - CsPbBr3 perovskite solar cells prepared from 0.08 M CsBr concentration delivered the highest efficiency of 2.6%. This was because the 0.08 M-perovskite film had good uniformity, low pinhole defect, and low PbBr2 impurities. Good cell stability, with an efficiency reduction of 10.0% of the initial value after 816 h under ambient environment, was achieved from the 0.08 M CsBr concentration cells.

Keywords: CsBr; inorganic cesium lead bromide perovskite; solar cells; hole transport material free

*Corresponding author: Tel.: (+66) 866408352 Fax: (+66) 043202374



Download data is not yet available.

Article Details

Original Research Articles


Kojima, A., Teshima, K., Shirai, Y. and Miyasaka, T., 2009. Organometal halide perovskites as visible-light sensitizers for photovoltaic cells. Journal of the American Chemical Society, 131, 6050-6051.

Im, J.H., Lee, C.R., Lee, J.W., Park, S.W. and Park, N.G., 2011. 6.5% efficient perovskite quantum-dot-sensitized solar cell. Nanoscale, 3, 4088-4093.

Kim, H.S., Lee, C.R., Im, J.H., Lee, K.B., Moeh T., Marchioro, A., Moon, S.J., Humphry-Baker, R., Yum, J.H., Moser, J.E., Gratzel, M. and Park, N.G., 2012. Lead iodide perovskite sensitized all-solid-state submicron thin film mesoscopic solar cell with efficiency exceeding 9%. Scientific Reports, 2, 591-597.

Burschka, J., Pellet, N., Moon, S.J., Humphry-Baker1, R., Gao1, P., Nazeeruddin, M.K. and Gratzel, M., 2013. Sequential deposition as a route to high-performance perovskite-sensitized solar cells. Nature, 499, 316-319.

Zhou, H., Chen, Q., Li, G., Luo, S., Song, T., Duan, H.S., Hong, Z., You, J., Liu, Y. and Yang, Y., 2014. Interface engineering of highly efficient perovskite solar cells. Science, 345, 542-546.

Yang, W.S., Noh, J.H., Jeon, N.J., Kim, Y.C., Ryu, S., Seo, J. and Seok, S., 2015. High-performance photovoltaic perovskite layers fabricated through intramolecular exchange. Science, 348, 1234-1237.

Bi, D., Tress, W., Dar, M.I., Gao, P., Luo, J., Renevier, C., Schenk, K., Abate, A., Giordano, F., Baena, J.P.C., Decoppet, J.D., Zakeeruddin, S.M., Nazeeruddin, M.K., Gratzel, M. and Hagfeldt, A., 2016. Efficient luminescent solar cells based on tailored mixed-cation perovskites. Science Advances, 2, 1501170,

Li, X., Bi, D., Yi, C., Décoppet, J.D., Luo, J., Zakeeruddin, S.M., Hagfeldt, A. and Grätzel M., 2016. A vacuum flash-assisted solution process for high-efficiency large-area perovskite solar cells. Science, 353, 58-62.

Green, M.A., Dunlop, E.D., Hohl-Ebinger, J., Yoshita, M., Kopidakis, N. and Ho-Baillie, A.W.Y., 2020. Solar cell efficiency tables (version 55). Progress in Photovoltaics, 28, 3-15.

Niu, G., Li, W., Meng, F., Wang, L., Dong, H. and Qiu, Y., 2014. Study on the stability of CH3NH3PbI3 films and the effect of post-modification by aluminum oxide in all-solid-state hybrid solar cells. Journal of Materials Chemistry A, 2, 705-710.

Wang, Z., Chenab, B. and Rogach, A.L., 2017. Synthesis, optical properties and applications of light-emitting copper nanoclusters. Nanoscale Horizons, 62, 135-146.

Zhang, X., Xu, B., Zhang, J., Gao, Y., Zheng, Y., Wang, K. and Sun, W., 2016. All-inorganic perovskite nanocrystals for high-efficiency light emitting diodes: dual-phase CsPbBr3-CsPb2Br5 composites. Advanced Functional Materials, 26, 4595-4600.

Wang, H.C., Lin, S.Y., Tang, A.C., Singh, B.P., Tong, H.C., Chen, C.Y., Lee, Y.C., Tsai, T.L. and Liu, R.S., 2016. Mesoporous silica particle integrated with all-inorganic CsPbBr3 perovskite quantum-dot nanocomposite (MP-PQDs) with high stability and wide color gamut used for backlight display. Angewandte Chemie International Edition, 55, 8056-8061.

Li, J., Gao, R., Gao, F., Lei, J., Wang, H., Wu, X., Li, J., Liu, H., Hua, X. and Liu, S.F., 2019. Fabrication of efficient CsPbBr3 perovskite solar cells by single-source thermal evaporation. Journal of Alloys and Compounds, 818, 152903,

Li, X., Tan, Y., Lai, H., Li, S., Chen, Y., Li, S., Xu, P. and Yang. J., 2019. All-inorganic CsPbBr3 perovskite solar cells with 10.45% efficiency by evaporation-assisted deposition and setting intermediate energy levels. ACS Applied Materials and Interfaces, 11, 29746-29752.

Chang, X., Li, W., Zhu, L., Liu, H., Geng, H., Xiang, S., Liu J. and Chen, H., 2016. Carbon-based CsPbBr3 perovskite solar cells: all-ambient processes and high thermal stability. ACS Applied Materials and Interfaces, 8, 33649-33655.

Kulbak, M., Gupta, S., Kedem, N., Levine, I., Bendikov, T., Hodes, G. and Cahen, D., 2016. Cesium enhances long-term stability of lead bromide perovskite-based solar cells. The Journal of Physical Chemistry Letters, 7, 167-172.

Sutton, R.J., Eperon, G.E., Miranda, L., Parrott, E.S., Kamino, B.A., Patel, J.B., Horantner, M.T., Johnston, M.B., Haghighirad, A.A., Moore, D.T. and Snaith, H.J., 2016. Bandgap-tunable cesium lead halide perovskites with high thermal stability for efficient solar cells. Advanced Energy Materials, 6, 1502458, htpps://

Liang, J., Wang, C., Wang, Y., Xu, Z., Lu, Z., Ma, Y., Zhu, H., Hu, Y., Xiao, C., Yi, X., Zhu, G., Lv, H., Ma, L., Chen, T., Tie, Z., Jin, Z. and Liu, J., 2016. All-inorganic perovskite solar cells. Journal of the American Chemical Society, 138, 15829-15832.

Li, J., Zhang, H., Wang, S., Long, D., Li, M., Guo, Y., Zhong, Z., Wu, K., Wang, D. and Zhang, T., 2017. Synthesis of all-inorganic CsPb2Br5 perovskite and determination of its luminescence mechanism. RSC Advances, 7, 54002-54007.

Wang, L., Liu, H., Zhang, Y. and Mohammed, O.F., 2020. Photoluminescence origin of zero dimensional Cs4PbBr6 perovskite. ACS Energy Letters, 5, 87-99.

Murtaza, G. And Ahmad, I., 2011. First principle study of the structural and optoelectronic properties of cubic perovskites CsPbM3 (M= Cl, Br, I). Physica B Condensed Matter, 406, 3222-3229.

Qian, J., Xu, B. and Tian, W.A., 2016. Comprehensive theoretical study of halide perovskites ABX3. Organic Electronics, 37, 61-73.

Yang, L., Wang, T., Min, Q., Liu, B., Liu, Z., Fan, X., Qiu, J., Xu, X., Yu, J. and Yu, X., 2019. High water resistance of monoclinic CsPbBr3 nanocrystals derived from zero-dimensional cesium lead halide perovskites. ACS Omega, 4, 6084-6091.

Zhang, X., Jin, Z., Zhang, J., Bai, D., Bian, H., Wang, K., Sun, J., Wang, Q. and Liu, S.F., 2018. All-ambient processed binary CsPbBr3–CsPb2Br5 perovskites with synergistic enhancement for high-efficiency Cs–Pb–Br-based solar cells. ACS Applied Materials and Interfaces, 10, 7145-7154.

Duan, J., Zhao, Y., He, B. and Tang, Q., 2018. High-purity inorganic perovskite films for solar cells with 9.72% efficiency. Angewandte Chemie International Edition, 57, 3787-3791.

Eijkelenkamp, A.J.H. and Vos, K., 1976. Reflectance measurements on single crystals of PbFCl, PbFBr, and PbBr2. Physica Status Solidi (b), 76, 769-778.

Tauc, J., 1968. Optical properties and electronic structure of amorphous Ge and Si. Materials Research Bulletin, 3, 37-46.

Kortüm, G., Braun, W. and Herzog, G., 1963. Principles and techniques of diffuse-reflectance spectroscopy. Angewandte Chemie International Edition, 2, 333-341.

Maes, J., Balcaen, L., Drijvers, E., Zhao, Q., De Roo, J., Vantomme, A., Vanhaecke, F., Geiregat, P. and Hens, Z., 2018. Light absorption coefficient of CsPbBr3 perovskite nanocrystals. The Journal of Physical Chemistry Letters, 9, 3093-3097.

Dursun, I., Bastiani, M.D., Turedi, B., Alamer, B., Shkurenko, A., Yin, J., El-Zohry, A.M., Gereige, I., AlSaggaf, A., Mohammed, O.F., Eddaoudi, M. and Bakr, O.M., 2017. CsPb2Br5 single crystals: Synthesis and characterization. ChemSusChem Communications, 10, 3746-3749.

Tang, M., He, B., Dou, D., Liu, Y., Duan, J., Zhao, Y., Chen, H. and Tang, Q., 2019. Toward efficient and air-stable carbon-based all-inorganic perovskite solar cells through substituting CsPbBr3 films with transition metal ions. Chemical Engineering Journal, 375, 121930,

Kumar, N., Rani, J. and Kurchania, R. 2021. Advancement in CsPbBr3 inorganic perovskite solar cells: Fabrication, efficiency and stability. Solar Energy, 221, 197-205.

Li, Y., Yang, X. and Xie, A., 2021. Preparation of surface modified CsPbBr3@CsPb2Br5 nanocrystals with high stability by a pseudo-peritectic method. Journal of Luminescence, 236, 118154,