Investigation of Structural, Electronic, and Optical Properties of CdAg 2 GeSe 4 and HgAg 2 GeSe 4 Amazing Photocatalyst Regarding with ZnAg 2 GeSe 4 and a Comparative Study by DFT Functionals

• Published in: ECS transactions 2022-04, Vol.107 (1), p.15375-15385
• Main Authors: Alam, Md. Monsur, Chakma, Unesco, Kumer, Ajoy, Islam, Md. Shariful, Khandaker, Nusrat Zahan, Hossain, Tomal, Chakma, Purak, Uddin, Jamal
• Format: Article
• Language: English
• ISSN: 1938-5862; 1938-6737
• DOI: 10.1149/10701.15375ecst

CdAg 2 GeSe 4 and HgAg 2 GeSe 4 have been designed by replacing the Zn atom by Cd and Hg atom of ZnAg 2 GeSe 4 for computational studies through first principle methods. In the beginning, five DFT functionals, such as GGA with PBE, GGA with RPBE, GGA with PW91, GGA with WC, and GGA with PBEsol, were used to calculate the electronic band structure and structural geometry for ZnAg 2 GeSe 4 , CdAg 2 GeSe 4 , and HgAg 2 GeSe 4 , and bandgap is at 0.84 eV, 0.92 eV, 0.68 eV, 0.78 eV, and 0.69 eV, with PBE, GGA with RPBE, GGA with PW91, GGA with WC, and GGA with PBEsol, respectively for ZnAg 2 GeSe 4 . The optical properties were calculated, and make a comparative study among ZnAg 2 GeSe 4 , CdAg 2 GeSe 4 , and HgAg 2 GeSe 4 . Finally, GGA with PBE is the most acceptable method, and HgAg 2 GeSe 4 shows higher absorption up to the convenience energy region of the photocatalyst.