A Theoretical Insight into the Physical Characteristics of Double Perovskite Rb2TlInBr6 for Renewable Energy Applications

Metal halide perovskites have gained prominence in optoelectronics recently, thanks to their unique optical and electrical properties, along with their adaptable morphologies. The current work reports the electronic, structural, mechanical, optical, and thermoelectric traits of Rb₂TlInBr₆ for the very first time. The confirmation of thermodynamic stability is evidenced by the negative value of the formation energy, while structural stability is established by calculating values for the tolerance factor and octahedral tilting. Elastic constants (C_ij) and mechanical attributes are evaluated to assess perovskites’ ability to resist external strains. Electronic band structures computed with GGA and mBJ potentials depict a semiconducting nature containing indirect bandgap of 1.8 and 2.42 eV, respectively. Optical characteristics of Rb₂TlInBr₆ ensure that it can be used effectively for optoelectronic applications. An insight into the thermoelectric characteristic is assessed through BoltzTraP code. The electrical conductivity and ZT reveal the ability of Rb₂TlInBr₆ to be utilized in green energy devices.