Ambient condition synthesis of Cs2AgBiBr6-double perovskite and its solar cell performances

Abstract

In the fast-advancing world of photovoltaic technologies, lead-free perovskite solar cells (PSCs) are gaining noteworthy attention due to their high tendency to offer a combination of environmental sustainability and improved stability. Here, we have explored the impact of temperature variations on the synthesis and the performance of Cs2AgBiBr6 as lead-free double perovskite solar cell, with a significant focus on boosting both power conversion efficiency (PCE) and ambient condition processability. Cs2AgBiBr6 thin films are synthesized using a spin-coating technique under ambient conditions, followed by annealing at 200–300°C. Various comprehensive characterization techniques are employed to analyze the structural, morphological, and optical properties of the films. Phase-pure Cs2AgBiBr6 films with excellent crystallinity and minimal defects result in smoother surface morphology and enhanced carrier transport properties at an improved annealing temperature of 275°C. Notably, for the very first time, we have used CuSCN as a hole transport layer (HTL) and silver as a contact for the fabrication of Cs2AgBiBr6-based PSCs that exhibited a PCE of 1.75% along with an improved ambient condition processability. These findings could play a vital role in designing and developing high-performance PSCs with environmental sustainability. © 2025 Elsevier B.V.