Ab initio Calculation of CuSbSe2 in Bulk and Monolayer for Solar Cell and Infrared Optoelectronic Applications

Abstract

Bala Idris, Abdullahi Lawal, Dauda Abubakar, Saddiq Abubakar Dalhatu and Buhari Aminu Balesa

The production of efficient, less toxic, and low-cost solar cell devices is still faced with numerous challenges. However, copper antimony selenide (CuSbSe₂) appears to be the more promising material due to cost-effectiveness, ease of availability, and less toxicity. Therefore, the exploration of the potential of this composite requires, comprehensive analysis of its structural, electronic, and optical properties. To accomplish this purpose, first-principles calculations employing the development of correction terms for the van der Waals interaction has been implemented in this study. Results obtained from structural properties calculations indicated that the role of van der Waals (vdW) interactions on structural properties of layered materials can be predicted from theoretical bases because results obtained for the lattice parameters using vdW on top of PBE were in good correlation with experimental results. The electronic properties investigations gave  values for the electronic band structures, partial and total densities of states. Indirect band gap was observed for bulk CuSbSe₂ with band gap value of 0.83 eV, which was also in agreement with experiment result. By reducing the dimension from bulk to monolayer a direct band gap smaller than that of bulk form was obtained, indicating that CuSbSe₂ is suitable for solar cell and near infrared optoelectronic applications. The optical gap of CuSbSe₂ in bulk and monolayer structure was found to be 0.83 and 0.21 eV respectively. Therefore, CuSbSe₂ can absorb photons, whose energy lies between that of the near infrared to visible light frequency. The study confirmed the importance of van der Waals interaction in predicting, structural, electronic and optical properties of layered materials. Analysis of optical parameters suggested that a device fabricated from these materials can be operated on a wide range of energy scale including solar cells, optical communications and biomedical imaging.