First-principles calculations to investigate structural and electronic properties of novel halides ZrIX (X = Cl, Br) for photovoltaic application

Abstract

In order to meet the increasing need for proficient photovoltaic materials, the electronic, structural, optical, and photovoltaic performance of ZrX2 (X = Cl, Br, I) and ZrIX (X = Cl, Br) monolayers have been examined by extensive Density Functional Theory (DFT) based calculation. The energetic, dynamic, and thermal stability of ZrIX (X = Cl, Br) monolayers have been verified by cohesive energy, phonon spectra, and molecular dynamics calculations respectively. Under the equilibrium state, the electronic properties show that ZrICl and ZrIBr monolayers exhibit semiconductor behavior with an indirect bandgap of 1.46 eV and 1.32 eV, respectively with HSE06 functional. The impact of strain on electronic and optical properties is also calculated. To check the optical performance of the ZrIX (X = Cl, Br) monolayer, its dielectric function, absorption coefficient, reflectivity, Transmittance, conductivity, and refractive index have been obtained. The absorption coefficient indicates that ZrIX (X = Cl, Br) monolayers have starting absorption in the visible region and utmost absorption in the UV region. This indicates that ZrIX (X = Cl, Br) monolayers have potential for optoelectronic and photovoltaic applications. The solar parameters have been computed using Shockley-Queisser's method. In addition, the calculated solar power conversion efficiency of 15.91 % for ZrICl and 14.13 % for ZrIBr monolayer indicates its light absorber capacity in the solar energy harvesting domain.