Evaluating the photocatalytic potential of the lead-free double perovskite halide Cs2AgBiBr6 for rhodamine-B degradation

The 21st-century challenge is to discover materials for energy and environmental recovery. Metal halide perovskites are ideal for photovoltaic and optoelectronic applications due to their tunable bandgap, high absorption, broad spectrum, and charge mobility. Improving their properties involves structural characterization to link composition, atomic organization, and performance. Correlating theoretical and experimental results is essential for optimizing their applications. This study examines Cs2AgBiBr6, synthesized mechanochemically, for rhodamine-B photodegradation. Its structure, determined by synchrotron X-ray diffraction and electron microscopy, confirms a double perovskite with the Fm 3 ̅ m space-group. UV-Vis spectroscopy reveals a 2.8 eV (X→L) indirect band gap transition. Cs2AgBiBr6 achieved a 100 % rhodamine-B degradation in 75 minutes, indicating high photocatalytic efficiency. This highlights Cs2AgBiBr6's versatility in photocatalytic and optoelectronic technologies.