Graphene-Enhanced TiO₂/Sr₃SbI₃ Architectures for High-Efficiency N719 Solar Cells
Abstract
In this study, we present for the first time a simulation-based design of dye-sensitized solar cell (DSSC) architecture, incorporating a TiO₂–graphene nanocomposite as the electron transport layer (ETL) with varying graphene doping concentrations (0.5%, 1%, 1.5%, 5%, 10%, and 20%). Strontium antimony iodide (Sr₃SbI₃) was employed as the hole transport layer (HTL), and the widely studied N719 dye was used as the light-absorbing material. While TiO₂ and N719 remain among the most commonly utilized materials in DSSCs, their performance in this configuration was evaluated through numerical simulations using the AFORS-HET tool. To optimize device performance, various factors were systematically investigated, including current density–voltage (J–V) characteristics, quantum efficiency (QE), energy band alignment, front and rear contact behavior, series and shunt resistances, and temperature dependence. The effect of incorporating graphene into TiO₂ on the ETL performance was examined in detail. Among the studied configurations, the TiO₂+1.5%Gr nanocomposite exhibited the highest power conversion efficiency (PCE), attributed to enhanced charge extraction and reduced interfacial recombination. The DSSC employing pristine TiO₂ as the ETL demonstrated a Voc of 0.44 V, a Jsc of 35.41 mA/cm², a fill factor (FF) of 76.22%, and a PCE of 12.08%. In comparison, the device using the TiO₂+1.5%Gr nanocomposite as the ETL achieved improved values: a Voc of 0.46 V, a Jsc of 35.46 mA/cm², a FF of 76.18%, and a PCE of 12.56%. These improvements are indicative of superior electrical conductivity, better energy level alignment, and reduced interfacial charge recombination.
Downloads
References
M.Q. Kareem, G.S. Jassim, R.F. Obaid, M.H. Shadhar, M.M. Kadhim, H.A. Almashhadani, A. Sarkar, Nile red based dye D–π–A as a promising material for solar cell applications, Chem. Pap. 76 (2022) 6167–6174. https://doi.org/10.1007/s11696-022-02290-1. University of Kirkuk.
M.Q. Kareem, M.M. Ameen, S.A. Hassan, S.M. Shareef, Synthesis of Tetrahedrite Zincian Nanocomposites via solvothermal process at low temperature, Ceram. Int. 50 (2024) 40005–40013. https://doi.org/10.1016/j.ceramint.2024.07.385. University of Kirkuk.
M. Kulbak, D. Cahen, G. Hodes, How important is the organic part of lead halide perovskite photovoltaic cells? Efficient CsPbBr3 cells, J. Phys. Chem. Lett. 6 (2015) 2452–2456.
M.H. Mohammadi, D. Fathi, M. Eskandari, NiO@GeSe core-shell nano-rod array as a new hole transfer layer in perovskite solar cells: A numerical study, Sol. Energy 204 (2020) 200–207. https://doi.org/10.1016/j.solener.2020.04.038.
A. ESHAGHI, A.A. AGHAEI, Effect of TiO2–graphene nanocomposite photoanode on dye-sensitized solar cell performance, Bull. Mater. Sci. 38 (2015) 1177–1182. https://doi.org/10.1007/s12034-015-0998-5.
G.G. Njema, J.K. Kibet, N. Rono, C.C. Ahia, Numerical simulation of a novel high performance solid‐state dye‐sensitised solar cell based on N719 dye, IET Optoelectron. 18 (2024) 96–120.
M.M. Tavakoli, P. Yadav, R. Tavakoli, J. Kong, Surface Engineering of TiO 2 ETL for Highly Efficient and Hysteresis‐Less Planar Perovskite Solar Cell (21.4%) with Enhanced Open‐Circuit Voltage and Stability, Adv. Energy Mater. 8 (2018). https://doi.org/10.1002/aenm.201800794.
D.K. Gorle, N. Chander, A simulation approach for device structure and thickness optimization of silicon heterojunction solar cells featuring TiO2 as carrier-selective contact, Mater. Today Proc. 39 (2021) 1916–1920. https://doi.org/10.1016/j.matpr.2020.08.312.
A.C. Ozurumba, N. V. Ogueke, C.A. Madu, E. Danladi, C.P. Mbachu, A.S. Yusuf, P.M. Gyuk, I. Hossain, SCAPS-1D simulated organometallic halide perovskites: A comparison of performance under Sub-Saharan temperature condition, Heliyon 10 (2024) e29599. https://doi.org/10.1016/j.heliyon.2024.e29599.
P. Sawicka-Chudy, M. Sibiński, G. Wisz, E. Rybak-Wilusz, M. Cholewa, Numerical analysis and optimization of Cu 2 O/TiO 2 , CuO/TiO 2 , heterojunction solar cells using SCAPS, J. Phys. Conf. Ser. 1033 (2018) 012002. https://doi.org/10.1088/1742-6596/1033/1/012002.
H. Al Dmour, SCAPS Numerical Analysis of Graphene Oxide /TiO2 Bulk Heterojunction Solar Cell Sensitized byN719 Ruthenium Dye, East Eur. J. Phys. (2023) 555–561. https://doi.org/10.26565/2312-4334-2023-3-65.
I.B.A. Ghani, M. Khalid, H. Yan, Y. El Arfaoui, B. Nawaz, J. Wang, Maximizing RbGeI3 perovskite solar cell efficiency through advanced TiO2/graphene nanocomposite electron transport layer, Optik (Stuttg). 320 (2025) 172116.
K. Patel, P.K. Tyagi, Multilayer graphene as a transparent conducting electrode in silicon heterojunction solar cells, AIP Adv. 5 (2015) 1–11. https://doi.org/10.1063/1.4927545.
Z.H. Li, J.N. Han, S.G. Cao, Z.H. Zhang, Graphene/MoSi2X4: A class of van der Waals heterojunctions with unique mechanical and optical properties and controllable electrical contacts, Appl. Surf. Sci. 614 (2023) 156095. https://doi.org/10.1016/j.apsusc.2022.156095.
T. Mahmoudi, Y. Wang, Y.-B. Hahn, Graphene and its derivatives for solar cells application, Nano Energy 47 (2018) 51–65. https://doi.org/10.1016/j.nanoen.2018.02.047.
M.Q. Kareem, S.S. Alimardan, W.M. Mohammad, I.M. Khudhair, Tailoring ETL/HTL combinations for high-performance ITO/i-ZnO/ZnS/SnSe/SnTe solar cells: A simulation approach, Results in Surfaces and Interfaces 18 (2025) 100411. https://doi.org/10.1016/j.rsurfi.2024.100411.
F. Jahantigh, M.J. Safikhani, The effect of HTM on the performance of solid-state dye-sanitized solar cells (SDSSCs): a SCAPS-1D simulation study, Appl. Phys. A 125 (2019) 276.
Gagandeep, M. Singh, R. Kumar, V. Singh, Graphene as charge transport layers in lead free perovskite solar cell, Mater. Res. Express 6 (2019) 115611. https://doi.org/10.1088/2053-1591/ab4b02.
J.T.-W. Wang, J.M. Ball, E.M. Barea, A. Abate, J.A. Alexander-Webber, J. Huang, M. Saliba, I. Mora-Sero, J. Bisquert, H.J. Snaith, R.J. Nicholas, Low-Temperature Processed Electron Collection Layers of Graphene/TiO 2 Nanocomposites in Thin Film Perovskite Solar Cells, Nano Lett. 14 (2014) 724–730. https://doi.org/10.1021/nl403997a.
M. Dadashbeik, D. Fathi, M. Eskandari, Design and simulation of perovskite solar cells based on graphene and TiO2/graphene nanocomposite as electron transport layer, Sol. Energy 207 (2020) 917–924. https://doi.org/10.1016/j.solener.2020.06.102.
M.Q. Kareem, H.A. Muhammad, W.M. Mohammad, Synthesis and characterization of La2S3-Mercaptoacetic acid nanocomposite films for enhanced gas sensing applications, Mater. Chem. Phys. 339 (2025) 130709. https://doi.org/10.1016/j.matchemphys.2025.130709.
M.Q. Kareem, S.M.S. Shareef, M.M. Ameen, S.A. Hassan, S.S. Alimardan, Probing the Morphology, Structure, and Optical Properties of Copper Samarium Borate Oxide Nanostructures, Baghdad Sci. J. (2024). https://doi.org/10.21123/bsj.2024.10351.
M.S. Islam, M.F. Rahman, M.R. Islam, Q. Mahmood, M. mana Al-Anazy, M.Z. Hasan, A. Ghosh, M. Husain, N. Rahman, M.K. Hossain, A.R. Chaudhry, A. Irfan, Investigation strain effects on the electronic, optical, and output performance of the novel inorganic halide perovskite Sr3SbI3 solar cell, Chinese J. Phys. 88 (2024) 270–286. https://doi.org/10.1016/j.cjph.2024.01.011.
A. Ghosh, A. Bakkar, Momina, N. Asmat, F. Ahmed, M.F.I. Buian, M. Sajid, J.R. Rajabathar, A.M. Karami, A. Nandi, M.A. Islam, Enhancing solar cell efficiency beyond 27% through the implementation of an efficient charge transport layer utilizing an innovative inorganic perovskite Sr3PI3, J. Phys. Chem. Solids 190 (2024) 112029. https://doi.org/10.1016/j.jpcs.2024.112029.
M.S. Reza, M.F. Rahman, A. Kuddus, M.K.A. Mohammed, A.K. Al-Mousoi, M.R. Islam, A. Ghosh, S. Bhattarai, R. Pandey, J. Madan, M.K. Hossain, Boosting efficiency above 28% using effective charge transport layer with Sr 3 SbI 3 based novel inorganic perovskite, RSC Adv. 13 (2023) 31330–31345. https://doi.org/10.1039/D3RA06137J.
H. Sung, N. Ahn, M.S. Jang, J. Lee, H. Yoon, N. Park, M. Choi, Transparent Conductive Oxide‐Free Graphene‐Based Perovskite Solar Cells with over 17% Efficiency, Adv. Energy Mater. 6 (2016). https://doi.org/10.1002/aenm.201501873.
M.K. Mim, S.K. Biswas, Performance Analysis of Sr 3 SbI 3 ‐Based Perovskite Solar Cell Using SCAPS‐1D Software, Adv. Mater. Sci. Eng. 2025 (2025). https://doi.org/10.1155/amse/7134012.
M.F. Rahman, M. Rahman, M.F. Hossain, B. Islam, S.R. Al Ahmed, A. Irfan, A Numerical Strategy for Achieving Efficiency Exceeding 32% with a Novel Lead‐Free Dual‐Absorber Solar Cell Using Ca 3 SbI 3 and Sr 3 SbI 3 Perovskites, Adv. Photonics Res. 6 (2025). https://doi.org/10.1002/adpr.202400148.
A. Klein, C. Körber, A. Wachau, F. Säuberlich, Y. Gassenbauer, S.P. Harvey, D.E. Proffit, T.O. Mason, Transparent conducting oxides for photovoltaics: Manipulation of fermi level, work function and energy band alignment, Materials (Basel). 3 (2010) 4892–4914.
F. De Angelis, S. Fantacci, A. Selloni, Alignment of the dye’s molecular levels with theTiO2 band edges in dye-sensitized solar cells: a DFT–TDDFT study, Nanotechnology 19 (2008) 424002.
M. Dhonde, K. Sahu, V.V.S. Murty, Cu-doped TiO2 nanoparticles/graphene composites for efficient dye-sensitized solar cells, Sol. Energy 220 (2021) 418–424.
S. Chala, N. Sengouga, F. Yakuphanoglu, Modeling the effect of defects on the performance of an n-CdO/p-Si solar cell, Vacuum 120 (2015) 81–88. https://doi.org/10.1016/j.vacuum.2015.05.019.
R. Pandey, R. Chaujar, Numerical simulation of rear contact silicon solar cell with a novel front surface design for the suppression of interface recombination and improved absorption, Curr. Appl. Phys. 16 (2016) 1581–1587. https://doi.org/10.1016/j.cap.2016.09.002.
C.-H. Huang, W.-J. Chuang, Dependence of performance parameters of CdTe solar cells on semiconductor properties studied by using SCAPS-1D, Vacuum 118 (2015) 32–37. https://doi.org/10.1016/j.vacuum.2015.03.008.
H. Park, D. Kim, E.-C. Cho, S.Q. Hussain, J. Park, D. Lim, S. Kim, S. Dutta, M. Kumar, Y. Kim, J. Yi, Effect on the reduction of the barrier height in rear-emitter silicon heterojunction solar cells using Ar plasma-treated ITO film, Curr. Appl. Phys. 20 (2020) 219–225. https://doi.org/10.1016/j.cap.2019.09.009.
C. Yadav, S. Kumar, Numerical simulation for optimization of ultra-thin n-type AZO and TiO2 based textured p-type c-Si Heterojunction Solar Cells, (2021). https://doi.org/10.21203/rs.3.rs-225454/v1.
O. Ahmad, A. Rashid, M.W. Ahmed, M.F. Nasir, I. Qasim, Performance evaluation of Au/p-CdTe/Cs2TiI6/n-TiO2/ITO solar cell using SCAPS-1D, Opt. Mater. (Amst). 117 (2021) 111105. https://doi.org/10.1016/j.optmat.2021.111105.
Z. Shi, A.H. Jayatissa, The impact of graphene on the fabrication of thin film solar cells: Current status and future prospects, Materials (Basel). 11 (2017). https://doi.org/10.3390/ma11010036.
M. Sk, S. Ghosh, 16.35 % efficient Cs2GeSnCl6 based heterojunction solar cell with hole-blocking SnO2 layer: DFT and SCAPS-1D simulation, Optik (Stuttg). 267 (2022) 169608. https://doi.org/10.1016/j.ijleo.2022.169608.
A. Chetia, D. Saikia, S. Sahu, Design and optimization of the performance of CsPbI3 based vertical photodetector using SCAPS simulation, Optik (Stuttg). 269 (2022) 169804. https://doi.org/10.1016/j.ijleo.2022.169804.
P. Roy, S. Tiwari, A. Khare, An investigation on the influence of temperature variation on the performance of tin (Sn) based perovskite solar cells using various transport layers and absorber layers, Results Opt. 4 (2021) 100083. https://doi.org/10.1016/j.rio.2021.100083.
B. Swatowska, W. Powroźnik, H. Czternastek, G. Lewińska, T. Stapiński, R. Pietruszka, B.S. Witkowski, M. Godlewski, Application properties of ZnO and AZO thin films obtained by the ALD method, Energies 14 (2021) 6271.
M. O’Byrne, B. Kerzabi, M. Abbarchi, A. Lifschitz, T. Zamora, V. Malgras, A. Gourdin, M. Modaresialam, D. Grosso, M. Putero, Investigation of the anatase-to-rutile transition for TiO2 sol-gel coatings with refractive index up to 2.7, Thin Solid Films 790 (2024) 140193.
J.W. Weber, V.E. Calado, M.C.M. Van De Sanden, Optical constants of graphene measured by spectroscopic ellipsometry, Appl. Phys. Lett. 97 (2010).
A. Dubey, R. Kumar, A. Chanda, Structural and Optical Study of TiO2-Graphene Composite Films, J. Sci. Res. 67 (2023).
N.S. Noorasid, F. Arith, A.Y. Firhat, A.N. Mustafa, A.S.M. Shah, SCAPS numerical analysis of solid-state dye-sensitized solar cell utilizing copper (I) iodide as hole transport layer, Eng. J. 26 (2022) 1–10.
A. Ghosh, M.F. Islam Buian, M. Maniruzzaman, M.M. Hossain, A.K. Azad, A.A. Miazee, I. Ragab, A.A. Hassan, H.A. Alrafai, S.K. Alla Abdelrahim, Numerical analysis and device modelling of a lead-free Sr 3 PI 3 /Sr 3 SbI 3 double absorber solar cell for enhanced efficiency, RSC Adv. 14 (2024) 26437–26456. https://doi.org/10.1039/D4RA05079G.
P.B. Rathod, S.A. Waghuley, Synthesis and study of optical properties of graphene/TiO2 composites using UV-VIS spectroscopy, J. Appl. Spectrosc. 83 (2016) 586–591.
A. Jamshidvand, R. Keshavarzi, V. Mirkhani, M. Moghadam, S. Tangestaninejad, I. Mohammadpoor-Baltork, N. Afzali, J. Nematollahi, M. Amini, A novel Ru (II) complex with high absorbance coefficient: efficient sensitizer for dye-sensitized solar cells, J. Mater. Sci. Mater. Electron. 32 (2021) 9345–9356.
S. Lee, S.J. Tark, C.S. Kim, D.Y. Jeong, J.C. Lee, W.M. Kim, D. Kim, Influence of front contact work function on silicon heterojunction solar cell performance, Curr. Appl. Phys. 13 (2013) 836–840. https://doi.org/10.1016/j.cap.2012.12.013.
J. Villanueva, J.A. Anta, E. Guillén, G. Oskam, Numerical simulation of the current− voltage curve in dye-sensitized solar cells, J. Phys. Chem. C 113 (2009) 19722–19731.
M.S. Reza, M.F. Rahman, A. Kuddus, M.S. Reza, M.A. Monnaf, M.R. Islam, S. Bhattarai, S. Al-Qaisi, L. Ben Farhat, S. Ezzine, Improving the efficiency of a new perovskite solar cell based on Sr3SbI3 by optimizing the hole transport layer, Energy & Fuels 38 (2024) 2327–2342.
Z. Khan, M.I. Khan, M. Ismail, M. Farooq, Harnessing Sr₃SbI₃ Perovskites with Optimized Charge Transport Layers for High-Efficiency Solar Energy Conversion, Results Eng. (2025) 106954.
M.K. Mim, S.K. Biswas, Performance Analysis of Sr3SbI3‐Based Perovskite Solar Cell Using SCAPS‐1D Software, Adv. Mater. Sci. Eng. 2025 (2025) 7134012.
F. Biccari, F. Gabelloni, E. Burzi, M. Gurioli, S. Pescetelli, A. Agresti, A.E. Del Rio Castillo, A. Ansaldo, E. Kymakis, F. Bonaccorso, Graphene‐based electron transport layers in perovskite solar cells: A step‐up for an efficient carrier collection, Adv. Energy Mater. 7 (2017) 1701349.
T. Sewela, R.O. Ocaya, T.D. Malevu, Recent insights into the transformative role of Graphene‐based/TiO2 electron transport layers for perovskite solar cells, Energy Sci. Eng. 13 (2025) 4–26.
D. Zhang, B. Li, P. Hang, J. Xie, Y. Yao, C. Kan, X. Yu, Y. Zhang, D. Yang, Mitigated front contact energy barrier for efficient and stable perovskite solar cells, Energy Environ. Sci. 17 (2024) 3848–3854.
R. Safa Sultana, A.N. Bahar, M. Asaduzzaman, K. Ahmed, Numerical modeling of a CdS/CdTe photovoltaic cell based on ZnTe BSF layer with optimum thickness of absorber layer, Cogent Eng. 4 (2017).
C. Wang, R.C.I. MacKenzie, U. Würfel, D. Neher, T. Kirchartz, C. Deibel, M. Saladina, Transport resistance dominates the fill factor losses in record organic solar cells, Adv. Energy Mater. (2025) 2405889.
S.S. Ali, W.S. Mohamed, H.A. Mohamed, Effect of series and shunt resistance on the performance of CZTSe thin film solar cell, Sohag J. Sci. 10 (2025) 75–79.
T. Moot, J.B. Patel, G. McAndrews, E.J. Wolf, D. Morales, I.E. Gould, B.A. Rosales, C.C. Boyd, L.M. Wheeler, P.A. Parilla, Temperature coefficients of perovskite photovoltaics for energy yield calculations, ACS Energy Lett. 6 (2021) 2038–2047.
I. Alam, M.A. Ashraf, Effect of different device parameters on tin-based perovskite solar cell coupled with In2S3 electron transport layer and CuSCN and Spiro-OMeTAD alternative hole transport layers for high-efficiency performance, Energy Sources, Part A Recover. Util. Environ. Eff. 46 (2024) 17080–17096.
A.S. Abdullah, F. Ahmad, M.H.I. Ibrahim, M.H. Ibrahim, A numerical simulation of novel solid-state dye-sensitized solar cell based on kesterite as the electrolyte, Results Opt. 14 (2024) 100625. https://doi.org/10.1016/j.rio.2024.100625.
M. Mehrabian, S. Dalir, Numerical simulation of highly efficient dye sensitized solar cell by replacing the liquid electrolyte with a semiconductor solid layer, Optik (Stuttg). 169 (2018) 214–223. https://doi.org/10.1016/j.ijleo.2018.05.059.
B.K. Korir, J.K. Kibet, S.M. Ngari, Simulated performance of a novel solid-state dye-sensitized solar cell based on phenyl-C61-butyric acid methyl ester (PC61BM) electron transport layer, Opt. Quantum Electron. 53 (2021) 368. https://doi.org/10.1007/s11082-021-03013-8.
N. Dematage, E.V.A. Premalal, A. Konno, Employment of CuI on Sb2S3 Extremely Thin Absorber Solar Cell: N719 Molecules as a Dual Role of a Recombination Blocking Agent and an Efficient Hole Shuttle, Int. J. Electrochem. Sci. 9 (2014) 1729–1737. https://doi.org/10.1016/S1452-3981(23)07886-0.
Copyright (c) 2025 Central Asian Journal of Theoretical and Applied Science
This work is licensed under a Creative Commons Attribution 4.0 International License.
