(264f) Electronic Structure of Cu2-Xse Nanoparticles for Plasmonic Catalysis: A Density Functional Theory Study

Copper selenide (Cu_2-XSe) is a non-precious metal plasmonic material with potential for many applications in sensing and catalysis. A detailed understanding of the electronic properties of Cu_2-XSe is important for tailoring and optimization of this material for specific applications. However, calculation of the electronic structure is very challenging because of the high mobility of the Cu atoms. We have used density functional theory to compute the band structure of ideal and defective structures of Cu_2-xSe for x=0, 0.25, and 0.5. The HSE06 hybrid functional is used in conjunction with the +U approach. It is known experimentally that the Cu atoms are disordered in Cu_2-xSe at room temperature. We use ab-initio molecular dynamics simulations explore the impact of Cu disorder on the electronic structure, particularly the band gap. We compare our calculations with experimental data for the band gap as a function of the composition