An In‐Depth Investigation of the Combined Optoelectronic and Photovoltaic Properties of Lead‐Free Cs₂AgBiBr₆ Double Perovskite Solar Cells Using DFT and SCAPS‐1D Frameworks

Abstract

In the backdrop of today's environmental priorities, where toxicity and stability hinder lead‐based perovskite solar cell (PSC) progress, the emergence of lead‐free alternatives like Cs2AgBiBr6 perovskites has gained significance. This study revolves around the comprehensive evaluation of Cs2AgBiBr6 as a potential photovoltaic (PV) material, using density functional theory (DFT) calculations with CASTEP. Revealing a vital bandgap of 1.654 eV and emphasizing the contributions of Ag‐4d and Br‐4p orbitals, this analysis also underscores Ag atoms' dominance in charge distribution. Optically, Cs2AgBiBr6 exhibits UV absorption peaks around 15 eV, intensifying with photon energy up to 3.75 eV, hinting at its promise for solar applications. Guided by DFT, forty configurations involving various electron transport layers (ETLs) and hole transport layers (HTLs) are explored. Among these, CNTS emerges as the prime HTL due to ideal absorber alignment. The spotlight architecture, FTO/AZnO/Cs2AgBiBr6/CNTS/Au, boasts exceptional efficiency (23.5%), Voc (1.38 V), Jsc (21.38 mA cm−2), and FF (79.9%). In contrast, FTO/CdZnS/Cs2AgBiBr6/CNTS/Au achieves a slightly lower 23.15% efficiency. Real‐world intricacies are probed, encompassing resistances, temperature, current–voltage (J–V) traits, and quantum efficiency (QE), enhancing practical relevance. These findings are thoughtfully contextualized within prior literature, showcasing the study's contributions to non‐toxic, inorganic perovskite solar technology. This work aspires to positively steer sustainable PV advancement.

Theoretical Simulation on Enhancing the Thin-Film Copper Zinc Tin Sulfide Solar Cell Performance Using MoS2, MoOx, and CuI as Efficient Hole Transport Layers

“…SCAPS-1D stands out as a precision tool, taking into meticulous consideration a multitude of factors, including the layer thickness, carrier concentration, defect density, buffer layers, metal work function, and back HTL. − It comprehensively addresses the complexities of semiconductor device behavior by solving the fundamental equations governing their operation, including the Poisson equation and continuity equations for both electrons and holes, as depicted in eqs – . This sophisticated software serves as a crucial tool in unraveling the intricate workings of the solar cell structure. ∂ ∂ x ( ε 0 ε R δ ψ δ x ) = prefix− q ( p − n + N D + − N A − + ρ def q ) prefix− ∂ J n ∂ x − R n + G = ∂ n ∂ t prefix− ∂ J p ∂ x − R p + G = ∂ p ∂ t Here, we explore the complex physics of our solar cell through an analysis of the important variables and formulas.…”