Optimization of CsPb0.75Sn0.25IBr2-based perovskite solar cells using different hole transport materials by SCAPS-1D

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Résumé

In recent years, there has been a significant increase in the literature on all-inorganic perovskite solar cells
(PSCs), which are potential candidates for resolving the impasse linked to the high volatility of the organic part
of hybrid perovskites. Among the light absorbers in CsPb1-xSnxIBr2 type, CsPb0.75Sn0.25IBr2 exhibits better film
quality, good phase stability under illumination and no phase segregation due to its low hysteresis. This makes
the CsPb0.75Sn0.25IBr2 light absorber is a viable alternative that combines efficiency and stability in photovoltaic
solar cells. In this paper, we used the SCAPS-1D simulation software to model the FTO/TiO2/CsPb0.75Sn0.25IBr2/
Spiro-OMeTAD/Au photovoltaic solar cell, with an initial power conversion efficiency (PCE) of 14.13 %. A study
was carried out to optimize the performance of the cell by varying the parameters of several layers. We studied
the effect of the absorber layer thickness, defect density, doping concentration and Auger recombination rate; the
effect of the TiO2 layer doping concentration and the TiO2/CsPb0.75Sn0.25IBr2 interface defect density. We also
considered the influence of changing the hole transport layer (HTL) and the back contact on the cell perfor
mance. Thus, we have modeled and optimized two solar cells, one using Spiro-OMeTAD, an organic HTL, and the
other NiO, an inorganic HTL, with efficiencies of up to 17,41 %. These efficiencies are significantly higher than
those obtained in a theoretical study (PCE =13.82 %) and in an experimental study (PCE =11.53 %). This study
suggests a way forward for the development of all-inorganic PSCs, offering improved efficiency and phase
stability.

Mots-clés

CsPb0.75Sn0.25IBr2 HTLs Perovskite Optimization SCAPS-1D