First-Principles Analysis on the Optoelectronic, Structural, Elastic and Transport Characteristics of Novel Fluoroperovskites Cs2TlAgF6 for Green Technology

Cs-based perovskites hold immense significance in the field of green technology due to their unique properties, offering promising avenues for efficient, low-cost devices. In this theoretical work, DFT has been employed to extensively scrutinize the physical properties of double fluoroperovskites Cs2TlAgF6. The modified Becke Johnson functional was used to take exchange-correlation effects into consideration accurately. From the calculated value of formation energy, volume optimization curve, Goldsmith tolerance factor and octahedral tilting, the structural stability is demonstrated. The band structure of Cs2TlAgF6 depicts a direct bandgap of 2.21 eV, proving its semiconducting nature. This study also assessed the mechanical properties in detail, showing the ductile character of Cs2TlAgF6. A thorough examination of optical characteristics reveals the potential application in a variety of photovoltaic devices due to its strong absorption in visible region. The transport attributes are accessed through large ZT value and other thermal parameters. With its exceptional heat-to-electricity conversion properties, this material shows promise for applications in thermoelectric devices, offering a sustainable way to generate electricity from waste heat. The larger value 0.788 of ZT depicts that material exhibit sufficient potential for generating energy from waste heat.