Determination of the gibbs formation energy of CuGaSe2 by EMF method

İDER M.

International Journal of Electrochemical Science, vol.15, no.9, pp.9049-9065, 2020 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 15 Issue: 9
  • Publication Date: 2020
  • Doi Number: 10.20964/2020.09.21
  • Journal Name: International Journal of Electrochemical Science
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.9049-9065
  • Keywords: CuGaSe2, EMF, Enthalpy of formation, Gibbs energy of formation, Solid-state electrochemical cell
  • Uşak University Affiliated: Yes

Abstract

The thermodynamic stability of the chalcopyrite CuGaSe2 compound semiconductor was studied. A solid-state electrochemical cell was employed to obtain the standard Gibbs energy of formation of CuGaSe2. The reversible EMF data of the following cell over the range of 818 to 950 K were measured: Pt, Ga(l), Ga2O3(s) // 15 YSZ // Ga2O3(s), Cu2Se(s), CuGaSe2(s), Cu, C, Pt. By using Cu2Se literature data with the EMF results, the following expression for the standard Gibbs energy of formation for CuGaSe2 was obtained: (Gf CuGaSe2) (kJ/mol) =-233.31 + 0.0075T(K) (818 to 950 K). The calculated G°f function shows that the ternary CuGaSe2 compound is more stable than the corresponding CuInSe2 by approximately 10 kJ/mol over the entire temperature range of the present investigation, which is consistent with the current phase diagram information.