Enhancing performance of low-temperature processed CsPbI₂Br all-inorganic perovskite solar cells using polyethylene oxide-modified TiO₂

Abstract

CsPbX₃-based (X = I, Br, Cl) inorganic perovskite solar cells (PSCs) prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability. However, the high trap state density and serious charge recombination between low-temperature processed TiO₂ film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs. Here a thin polyethylene oxide (PEO) layer is employed to modify TiO₂ film to passivate traps and promote carrier collection. The impacts of PEO layer on microstructure and photoelectric characteristics of TiO₂ film and related devices are systematically studied. Characterization results suggest that PEO modification can reduce the surface roughness of TiO₂ film, decrease its average surface potential, and passivate trap states. At optimal conditions, the champion efficiency of CsPbI₂Br PSCs with PEO-modified TiO₂ (PEO-PSCs) has been improved to 11.24% from 9.03% of reference PSCs. Moreover, the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs.

Keywords

polyethylene oxide-modified TiO₂ film / low-temperature process / CsPbI₂Br-based all-inorganic perovskite solar cells / photovoltaic performance

References

[[1]] L. Chu, S.B. Zhai, W. Ahmad, et al., High-performance large-area perovskite photovoltaic modules, Nano Res. Energy, 1(2022), No. 2, art. No. 9120024.

[[2]] Z.T. Wang, Q.W. Tian, H. Zhang, et al., Managing multiple halide-related defects for efficient and stable inorganic perovskite solar cells, Angew. Chem. Int. Ed., 62(2023), No. 30, art. No. e202305815.

[[3]] Zhang SY, He J, Guo X, et al.. Crystallization dynamic control of perovskite films with suppressed phase transition and reduced defects for highly efficient and stable all-inorganic perovskite solar cells. ACS Mater. Lett., 2023, 5(6): 1497,

[[4]] Eperon GE, Paterno GM, Sutton RJ, et al.. Inorganic caesium lead iodide perovskite solar cells. J. Mater. Chem. A, 2015, 3(39): 19688,

[[5]] J.X. Zhang, G.Z. Zhang, P.Y. Su, et al., 1D choline-PbI₃-based heterostructure boosts efficiency and stability of CsPbI₃ perovskite solar cells, Angew. Chem. Int. Ed., 62(2023), No. 25, art. No. e202303486.

[[6]] Q.S. Zeng, X.Y. Zhang, C.M. Liu, et al., Inorganic CsPbI₂Br perovskite solar cells: The progress and perspective, Sol. RRL, 3(2019), No. 1, art. No. 1800239.

[[7]] Dong HP, Li Y, Wang SF, et al.. Interface engineering of perovskite solar cells with PEO for improved performance. J. Mater. Chem A, 2015, 3(18): 9999,

[[8]] L. Yan, Q.F. Xue, M.Y. Liu, et al., Interface engineering for all-inorganic CsPbI₂Br perovskite solar cells with efficiency over 14%, Adv. Mater., 30(2018), No. 33, art. No. 1802509.

[[9]] S.M. Yang, H. Zhao, Y. Han, C.Y. Duan, Z.K. Liu, and S.F. Liu, Europium and acetate co-doping strategy for developing stable and efficient CsPbI₂Br perovskite solar cells, Small, 15(2019), No. 46, art. No. 1904387.

[[10]] E.C. Shen, J.D. Chen, Y. Tian, et al., Interfacial energy level tuning for efficient and thermostable CsPbI₂Br perovskite solar cells, Adv. Sci., 7(2020), No. 1, art. No. 1901952.

[[11]] Q.Y. Guo, J.L. Duan, J.S. Zhang, et al., Universal dynamic liquid interface for healing perovskite solar cells, Adv. Mater., 34(2022), No. 26, art. No. 2202301.

[[12]] Zhou HP, Chen Q, Li G, et al.. Interface engineering of highly efficient perovskite solar cells. Science, 2014, 345(6196): 542,

[[13]] He JJ, Ge B, Hou Y, Yang S, Yang HG. A dendrite-structured RbX (X=Br, I) interlayer for CsPbI₂Br perovskite solar cells with over 15 % stabilized efficiency. ChemSusChem, 2020, 13(20): 5443,

[[14]] Zhao AR, Han Y, Che YH, et al.. High-quality borophene quantum dot realization and their application in a photovoltaic device. J. Mater. Chem. A, 2021, 9(42): 24036,

[[15]] Wang WR, Lin Y, Zhang GZ, et al.. Modification of compact TiO₂ layer by TiCl₄–TiCl₃ mixture treatment and construction of high-efficiency carbon-based CsPbI₂Br perovskite solar cells. J. Energy Chem., 2021, 63: 442,

[[16]] Duan CH, Wen QY, Fan Y, Li J, Liu ZD, Yan KY. Improving the stability and scalability of all-inorganic inverted CsPbI₂Br perovskite solar cell. J. Energy Chem., 2022, 68: 176,

[[17]] Y. Jing, X. Liu, Y. Xu, et al., Amorphous antimony sulfide nanoparticles construct multi-contact electron transport layers for efficient carbon-based all-inorganic CsPbI₂Br perovskite solar cells, Chem. Eng. J., 455(2023), art. No. 140871.

[[18]] S. You, H. Wang, S.Q. Bi, et al., A biopolymer heparin sodium interlayer anchoring TiO₂ and MAPbI₃ enhances trap passivation and device stability in perovskite solar cells, Adv. Mater., 30(2018), No. 22, art. No. 1706924.

[[19]] Tan J, Dou J, Duan JL, Zhao YY, He BL, Tang QW. A trifunctional polyethylene oxide buffer layer for stable and efficient all-inorganic CsPbBr₃ perovskite solar cells. Dalton Trans., 2023, 52(13): 4038,

[[20]] Tian K, Lu Y, Liu R, Loh XJ, Young DJ. Low-threshold amplified spontaneous emission from air-stable CsPb-Br₃ perovskite films containing trace amounts of polyethylene oxide. ChemPlusChem, 2021, 86(11): 1537,

[[21]] Z. Uddin, J.H. Ran, E. Stathatos, and B. Yang, Improving thermal stability of perovskite solar cells by thermoplastic additive engineering, Energies, 16(2023), No. 9, art. No. 3621.

[[22]] J.J. Yang, X. Yu, X.B. Lu, et al., Bifunctional passivation for efficient and stable low-temperature processed all-inorganic CsPbIBr₂ perovskite solar cells, Surf. Interfaces, 32(2022), art. No. 102097.

[[23]] P.L. Qin, T. Wu, Z.C. Wang, et al., Vitrification transformation of poly(ethylene oxide) activating interface passivation for high-efficiency perovskite solar cells, Sol. RRL, 3(2019), No. 10, art. No. 1900134.

[[24]] Arora N, Dar MI, Hinderhofer A, et al.. Perovskite solar cells with CuSCN hole extraction layers yield stabilized efficiencies greater than 20%. Science, 2017, 358(6364): 768,

[[25]] Chen Q, Zhou HP, Hong ZR, et al.. Planar heterojunction perovskite solar cells via vapor-assisted solution process. J. Am. Chem. Soc., 2014, 136(2): 622,

[[26]] Nejand BA, Ahmadi V, Gharibzadeh S, Shahverdi HR. Cuprous oxide as a potential low-cost hole-transport material for stable perovskite solar cells. ChemSusChem, 2016, 9(3): 302,

[[27]] Aftab A, Ahmad MI. A review of stability and progress in tin halide perovskite solar cell. Sol. Energy, 2021, 216: 26,

[[28]] Snaith HJ, Abate A, Ball JM, et al.. Anomalous hysteresis in perovskite solar cells. J. Phys. Chem. Lett., 2014, 5(9): 1511,

[[29]] J.Y. Li, B.Y. Huang, E.N. Esfahani, et al., Touching is believing: Interrogating halide perovskite solar cells at the nanoscale via scanning probe microscopy, NPJ Quantum Mater., 2(2017), art. No. 56.

[[30]] B.P. Nguyen, G.Y. Kim, W. Jo, B.J. Kim, and H.S. Jung, Trapping charges at grain boundaries and degradation of CH₃NH₃Pb(I_1−xBr_x)₃ perovskite solar cells, Nanotechnology, 28(2017), No. 31, art. No. 315402.

[[31]] Heo JH, You MS, Chang MH, et al.. Hysteresis-less mesoscopic CH₃NH₃PbI₃ perovskite hybrid solar cells by introduction of Li-treated TiO₂ electrode. Nano Energy, 2015, 15: 530,

[[32]] Boopathi KM, Mohan R, Huang TY, et al.. Synergistic improvements in stability and performance of lead iodide perovskite solar cells incorporating salt additives. J. Mater. Chem. A, 2016, 4(5): 1591,

[[33]] Liu YF, Wu ZL, Dou YX, et al.. Formamidinium-based perovskite solar cells with enhanced moisture stability and performance via confined pressure annealing. J. Phys. Chem. C, 2020, 124(23): 12249,

[[34]] Y. Dong, W.J. Shen, W. Dong, et al., Chlorobenzenesulfonic potassium salts as the efficient multifunctional passivator for the buried interface in regular perovskite solar cells, Adv. Energy Mater., 12(2022), No. 20, art. No. 2200417.

[[35]] Gao YX, Dong YN, Huang KQ, et al.. Highly efficient, solution-processed CsPbI₂Br planar heterojunction perovskite solar cells via flash annealing. ACS Photonics, 2018, 5(10): 4104,

[[36]] J.R. Zhang, D.L. Bai, Z.W. Jin, et al., 3D–2D–0D interface profiling for record efficiency all-inorganic CsPbBrI₂ perovskite solar cells with superior stability, Adv. Energy Mater., 8(2018), No. 15, art. No. 1703246.

[[37]] Y. Xu, F.L. Liu, R.S. Li, et al., Mxene regulates the stress of perovskite and improves interface contact for high-efficiency carbon-based all-inorganic solar cells, Chem. Eng. J., 461(2023), art. No. 141895.

[[38]] Y.W. Duan, K. He, L. Yang, J. Xu, W.J. Zhao, and Z.K. Liu, 24.20%-efficiency MA-free perovskite solar cells enabled by siloxane derivative interface engineering, Small, 18(2022), No. 48, art. No. 2204733.

[[39]] Zhao YX, Nardes AM, Zhu K. Mesoporous perovskite solar cells: Material composition, charge-carrier dynamics, and device characteristics. Faraday Discuss., 2014, 176: 301,

[[40]] Park M, Kim JY, Son HJ, Lee CH, Jang SS, Ko MJ. Low-temperature solution-processed Li-doped SnO₂ as an effective electron transporting layer for high-performance flexible and wearable perovskite solar cells. Nano Energy, 2016, 26: 208,

[[41]] Yu ZH, Chen BL, Liu P, et al.. Stable organic-inorganic perovskite solar cells without hole-conductor layer achieved via cell structure design and contact engineering. Adv. Funct. Mater., 2016, 26(27): 4866,

[[42]] Lin LY, Yeh MH, Lee CP, Chou CY, Vittal R, Ho KC. Enhanced performance of a flexible dye-sensitized solar cell with a composite semiconductor film of ZnO nanorods and ZnO nanoparticles. Electrochim. Acta, 2012, 62: 341,

[[43]] Yang S, Yue WB, Zhu J, Ren Y, Yang XJ. Graphene-based mesoporous SnO₂ with enhanced electrochemical performance for lithium-ion batteries. Adv. Funct. Mater., 2013, 23(28): 3570,

[[44]] Mahmud MA, Elumalai NK, Upama MB, et al.. Single vs mixed organic cation for low temperature processed perovskite solar cells. Electrochim. Acta, 2016, 222: 1510,

[[45]] Li XM, Jia PC, Meng FW, et al.. Propylamine hydrobromide passivated tin-based perovskites to efficient solar cells. Int. J. Miner. Metall. Mater., 2023, 30(10): 1965,

[[46]] H.R. Sun, J. Zhang, X.L. Gan, et al., Pb-reduced CsPb_0.9Zn_0.1I₂Br thin films for efficient perovskite solar cells, Adv. Energy Mater., 9(2019), No. 25, art. No. 1900896.

[[47]] W. Chen, Y.H. Wu, J. Fan, et al., Understanding the doping effect on NiO: Toward high-performance inverted perovskite solar cells, Adv. Energy Mater., 8(2018), 19, art. No. 1703519.

[[48]] J.J. Tian, Q.F. Xue, X.F. Tang, et al., Dual interfacial design for efficient CsPbI₂Br perovskite solar cells with improved photostability, Adv. Mater., 31(2019), No. 23, art. No. 1901152.

[[49]] Azmi R, Oh SH, Jang SY. High-efficiency colloidal quantum dot photovoltaic devices using chemically modified heterojunctions. ACS Energy Lett., 2016, 1(1): 100,

[[50]] Y. Zhou, X. Zhang, X.B. Lu, et al., Promoting the hole extraction with Co₃O₄ nanomaterials for efficient carbon-based CsPbI₂Br perovskite solar cells, Sol. RRL, 3(2019), No. 4, art. No. 1800315.

[[51]] Duan JL, Zhao YY, He BL, Tang QW. High-purity inorganic perovskite films for solar cells with 9.72 % efficiency. Angew. Chem. Int. Ed, 2018, 57(14): 3787,

[[52]] Zhang M, Gao W, Zhang FJ, et al.. Efficient ternary non-fullerene polymer solar cells with PCE of 11.92% and FF of 76.5%. Energy Environ. Sci., 2018, 11(4): 841,