Performance improvement of HTL-free perovskite solar cells with the graded approach by numerical simulation

• Published in: The Journal of physics and chemistry of solids 2024-01, Vol.184, p.111691, Article 111691
• Main Authors: Bhattarai, Sagar, Hossain, M. Khalid, Madan, Jaya, Pandey, Rahul, Samajdar, D.P., Ansari, Mohd Zahid, Hossain, Ismail, Ezzine, Safa, Amami, Mongi
• Format: Article
• Language: English
• Subjects: Perovskite absorber; Power conversion efficiency; Quantum efficiency; SCAPS
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/j.jpcs.2023.111691

In the exponential growth of perovskite solar cells (PSCs), there remains certain concerns regarding the wide-range incident photons absorption. The doubly graded lead-free absorber in the PSC has been recommended for solving these problems. The absorber material in the PSC is based on the lead-free as well as tin-based perovskite i.e., CH3NH3SnI3, that is one of the precarious parameters due to the non-toxic behavior as well as the lower band gap of 1.3 eV that can be useful in broad visible absorption spectrum than the traditional CH3NH3PbI3 layer. Furthermore, the quantum efficiency (QE) as well as the power conversion efficiency (PCE) in the double-graded configuration of the PSC can be improve. The outcomes of the present numerical simulations examine the solar cells' single and double grading strategy. Further, we use a novel approach of HTL-free PSC, that can lower the manufacturing cost and the defectivity. The present work compares single and double-grading Perovskite Absorber Layer (PAL) for obtaining high PCE. The results are exciting as the highest open-circuit voltage (VOC) of 0.965V, higher short-current density (JSC) of 35.26 mA/cm2, and high fill factor (FF) of 86.40% in the doubly-graded PSC shows a much-optimized PCE of nearly 29.35% that can be convenient for fabricating much efficient PSC device. •The double graded absorber were simulated for higher performance parameters.•The HTL free along with optimized graded approach enhanced the efficiency.•An optimum power conversion efficiency of 29.35% was achieved using the novel technique.•The current study will pave the way for the development of highly efficient solar cells in the future.•The present work can be valuable for futuristic device optimization of tin-based solar cells.