Numerical optimization of photovoltaic performance of cesium titanium bromide perovskite solar cells using dual copper oxide hole transport layers

P. R. Jubu; O. D. Abi; Z. S. Mbalaha; I. K. Nwokolo; A. O. Aransiola; C. Amakom; K. Udofia; A. A. Goje; I. I. Ayogu; D. S. Igba; M. M. Gururani; E. E. Oguzie

doi:10.46481/asr.2026.5.2.488

Authors

P. R. Jubu
Africa Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria;

Department of Industrial Physics, Joseph Sarwuan Tarka University Makurdi (Federal University of Agriculture Makurdi) P.M.B. 2373, Makurdi, Benue State, Nigeria
O. D. Abi
Department of Physics, Joseph Sarwuan Tarka University P.M.B. 2373, Makurdi, Benue State, Nigeria
Z. S. Mbalaha
Department of Industrial Physics, Joseph Sarwuan Tarka University Makurdi (Federal University of Agriculture Makurdi) P.M.B. 2373, Makurdi, Benue State, Nigeria
I. K. Nwokolo
Africa Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria
A. O. Aransiola
Africa Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria;

Department of Electronic and Electrical Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria
C. Amakom
Africa Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria;

Department of Physics, Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria
K. Udofia
Africa Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria;

Department of Physics, Akwa Ibom State University, Akwa Ibom State, Nigeria
A. A. Goje
Africa Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria;

Department of Applied Physics, Federal Polytechnic Damaturu, Nigeria
I. I. Ayogu
Africa Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria
D. S. Igba
Department of Industrial Physics, Joseph Sarwuan Tarka University Makurdi (Federal University of Agriculture Makurdi) P.M.B. 2373, Makurdi, Benue State, Nigeria
M. M. Gururani
Department of Physics, M.B. Government P.G. College, Haldwani (Uttarakhand), India
E. E. Oguzie
[email protected]

Africa Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria;

Department of Chemistry, Federal University of Technology Owerri (FUTO), P.M.B. 1526 Owerri, Imo State, Nigeria

Keywords:

Cs2TiBr6 perovskite, Perovskite solar cell, Cu2O/CuO, HTL-free perovskite solar cell

Abstract

This work provides a comprehensive numerical evaluation by using SCAPS-1D software for designing efficient lead-free Cs₂TiBr₆-based perovskite solar cells (PSCs) based on all-inorganic carrier transport layers. The copper oxide hole transport layer (HTL) is introduced in the Cs₂TiBr₆-based PSC for the first time, recording a power conversion efficiency (PCE) that is superior to the values reported in the literature. The prototype FTO/CeO_x/Cs₂TiBr₆/Cu₂O/CuO/Au cell achieved a power conversion efficiency (PCE) of 8.67%. Optimization of several factors, including layer thickness, defect density, interface defect density, back metal contact, electron capture cross-section, and absorber bandgap, yielded an enhanced PCE of 30.75% for the optimized FTO/CeO_x/Cs₂TiBr₆/Cu₂O/CuO/Pt PSC. Simplified device architectures were investigated. The simple FTO/CeO_x/Cs₂TiBr₆/Cu₂O/Pt cell delivered a comparable PCE of 30.76%. The HTL-free FTO/CeO_x/Cs₂TiBr₆/Pt design recorded a lower PCE of 22.32%. The optimized Cu₂O/CuO HTL-assisted device exhibited robust thermal performance, with only a modest decrease in PCE (30.99% to 28.16%) with increasing temperature (290 K--400 K). The improved photovoltaic performance of the optimized HTL-assisted devices can be attributed to enhancement in light absorption and carrier generation. An increased built-in field and improved carrier collection also contributed to this improvement. The higher work function of Pt (5.7 eV) formed a better ohmic back contact with the optimized devices, further improving carrier collection.

Dimensions

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Numerical optimization of photovoltaic performance of cesium titanium bromide perovskite solar cells using dual copper oxide hole transport layers

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