An effective strategy of indium half-doping to stabilize the structure and improve optoelectronic characteristics of Tl-Co based double perovskite: First principles study

Abstract

Doping can improve the structural stability and photoelectric properties of perovskite materials. In this study, indium element was added into Tl-Co double based perovskite material to stabilize its structure and improve its photoelectric performance. The results show that the doped material Cs2In0.5Tl0.5CoX6(X = I, Br, Cl) has better ductility and stability than the original Cs2TlCoI6 by elastic constants and phonon spectra. Moreover, indium doping can improve the band structure of Tl-Co double-base perovskite materials, such as changing the band value to the optimal band gap value of solar energy absorber and transforming from indirect band structure to quasi-direct band structure. In terms of optical properties, indium doping can expand the wavelength range of the material's light absorption, making its absorption spectrum more matching with the simulated AM1.5 spectrum. Cs2In0.5Tl0.5CoCl6 is proposed to be a promising candidate for optoelectronic applications based on its structural stability, bandgap value and optical absorption spectrum.

Keywords

• Indium doping
• Double perovskite
• Structural stability
• Optimal bandgap
• Solar absorber