American Journal of Energy Research
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American Journal of Energy Research. 2024, 12(1), 1-7
DOI: 10.12691/ajer-12-1-1
Open AccessArticle

Modeling and Analysis of a Mixed Sn-Ge Lead Free Perovskite Based Solar Cells

S. Seck1, , A. Sow1, M. S. Mané1, A. Ndiaye1, E. M. Keita1, B. Ndiaye1, B. Mbow1 and C. Sène1

1Physics Department, Faculty of Sciences and Technology, Laboratory of Semiconductors and Solar Energy, University Cheikh Anta Diop, Dakar Country

Pub. Date: February 16, 2024

Cite this paper:
S. Seck, A. Sow, M. S. Mané, A. Ndiaye, E. M. Keita, B. Ndiaye, B. Mbow and C. Sène. Modeling and Analysis of a Mixed Sn-Ge Lead Free Perovskite Based Solar Cells. American Journal of Energy Research. 2024; 12(1):1-7. doi: 10.12691/ajer-12-1-1


Recently, organic/inorganic hybrid perovskite materials have attracted particular interest in the research community for future generations of photovoltaic systems, due to their manufacturing process ease by solution treatment, their low cost and exceptional optoelectronic properties. Owing mainly to these superior optoelectronic properties and the long carrier lifetime in these materials, perovskite-based photovoltaic devices have achieved high conversion efficiencies up to 25%. However, the presence of lead which is very environmental and human harmful together with the stability issues of these materials constitute major problems encountered in the development of photovoltaic devices based on these materials. Faced with these problems, a large number of alternative absorber materials based on lead-free perovskites and/or inorganic perovskites are increasingly being explored. In this work, we carried out a modeling study of photovoltaic devices using the CH3NH3Sn1-yGeyI3 lead-free perovskite as absorbing material. The ZnO(n+)/Cu2O(n)/CH3NH3Sn1-yGeyI3(p) structure is considered for this purpose in which 0≤y≤1. The evolution of the internal quantum efficiency is analyzed as a function of the relative proportion of tin and germanium in the perovskite and also as a function of various other parameters including the thickness of the base and the minority carrier diffusion length in this material. The substitution of lead by metals such as tin and/or germanium leads to lead-free perovskites having opto-electronic properties adapted to the production of high-performance photovoltaic devices. Materials of high optoelectronic and structural properties are in particular obtained for Ge content in the perovskite less than 0.50. In this range of the Ge content, our study shows that the best photovoltaic devices are obtained for values of the germanium (Ge) content close to 0.25

perovskite photovoltaic cell quantum efficiency diffusion length absorber thickness

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