Achieving efficiency above 30% with new inorganic cubic perovskites X2SnBr6 (X = Cs, Rb, K, Na) via DFT and SCAPS-1D

Md Ferdous Rahman; Tanvir Al Galib; Md Azizur Rahman; Md Hafizur Rahman; Md Harun-Or-Rashid; Md Al Ijajul Islam; Md Monirul Islam; N Dhahri; Ahmad Irfan

doi:10.1039/d4cp01883d

Achieving efficiency above 30% with new inorganic cubic perovskites X₂SnBr₆ (X = Cs, Rb, K, Na) via DFT and SCAPS-1D

Phys Chem Chem Phys. 2024 Dec 17. doi: 10.1039/d4cp01883d. Online ahead of print.

Authors

Md Ferdous Rahman¹, Tanvir Al Galib¹, Md Azizur Rahman¹, Md Hafizur Rahman¹, Md Harun-Or-Rashid¹, Md Al Ijajul Islam¹, Md Monirul Islam¹, N Dhahri², Ahmad Irfan³

Affiliations

¹ Advanced Energy Materials and Solar Cell Research Laboratory, Department of Electrical and Electronic Engineering, Begum Rokeya University, Rangpur 5400, Bangladesh. ferdousapee@gmail.com.
² Department of Physics, College of Science, Northern Border University, Arar, Saudi Arabia.
³ Department of Chemistry, College of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.

PMID: 39688345
DOI: 10.1039/d4cp01883d

Abstract

The solar sector is shifting towards lead-free, inorganic cubic halide perovskites due to their superior structural, electronic, and optoelectronic properties. This study uses density functional theory (DFT) to examine the structural, electronic, and optical properties of X₂SnBr₆ (X = Cs, Rb, K, Na) and assesses their photovoltaic performance through the Solar Cell Capacitance Simulator - One Dimensional (SCAPS-1D). The results show each material has a direct band gap at the Γ-point, low optical losses, and high absorption, making them promising for solar and optoelectronic applications. For Cs₂SnBr₆, Rb₂SnBr₆, K₂SnBr₆, and Na₂SnBr₆ absorbers with TiO₂ electron transport layer (ETL), power conversion efficiencies (PCE) of 29.22%, 27.25%, 30.62%, and 29.51% were achieved, with open-circuit voltages (V_OC) of 1.02, 0.87, 0.83, and 0.77 V, short-circuit currents (J_SC) of 32.27, 36.72, 42.69, and 45.48 mA cm^-2, and fill factors (FF) of 88.38, 85.18, 85.96, and 81.85%, respectively. Variations in X-cation size notably influence bandgap energy, band structure, and optoelectronic properties, impacting solar cell efficiency. This study supports the development of lead-free hybrid solar cells and other optoelectronic devices.