Thermodynamic stability and homogeneity of cuprous selenide by emf and coulometric titration

İDER M.

Solid State Ionics, vol.329, pp.140-148, 2019 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 329
  • Publication Date: 2019
  • Doi Number: 10.1016/j.ssi.2018.11.018
  • Journal Name: Solid State Ionics
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.140-148
  • Keywords: Cuprous selenide, Electromotive force measurements, Enthalpy of formation, Gibbs energy of formation, Solid-state electrochemical cell
  • Uşak University Affiliated: Yes

Abstract

The thermodynamic stability of Cu2Se has been measured using the following galvanic cell over the range of 852 to 972 K. Pt,Cus,Cu2Os//15YSZ//Cu2Ses,Cu2Os,Ses,C,PtI The emf of cell I was measured to be E±0.79mV=326.58+0.153TK By combining available Gibnbs energy data from literature, the Gibbs energy of formation of Cu2Se has been found to be (ΔGο fCu2Se±0.15kJmol−1=−0.0295TK−63.02 The homogeneity range of β-Cu2−xSe has been determined by coulometric titration at 900 K on the following cell Pt,Cu2−xSes//15YSZ//Cu2Os,Cus,PtII The Cu mole fraction change between the selenium-rich and the copper-rich boundaries was measured as Δx = 0.012 at 900 K.