Density and viscosity behaviour of EBPBF4, TBPBF4 and HBPBF4 in acetonitrile solutions at different temperatures at T = (293.15–323.15) K. (July 2021)

• Record Type: Journal Article
• Authors: Xu, Jian; Zhao, Leiqiang; Xiong, Donggen; Zhang, Ze; Yu, Ji; Cai, Jianxin; Yang, Zhenyu
• Is Part Of: Journal of chemical thermodynamics. Volume 158(2021)
• Publication Date: 2021-07
• Subjects: Density -- Viscosity -- Quaternary phosphate salt electrolyte -- Apparent molar volume -- Viscosity B-coefficient -- Activation energy of viscous flow; Thermodynamics -- Periodicals; Thermochemistry -- Periodicals; Thermodynamique -- Périodiques; Thermochimie -- Périodiques; Thermochemistry; Thermodynamics; Periodicals; 541.369
• DOI: 10.1016/j.jct.2021.106467
• Languages: English
• ISSNs: 0021-9614

Abstract

Graphical abstract: Highlights: Densities and viscosities of EBPBF4, TBPBF4 and HBPBF4 in AN were measured at different temperatures. Some thermodynamic parameters obtained to analyze the interaction between solutes and solvents. The change of d B/ d T indicates the decreasing hydrodynamic volume of ions with increasing temperature. The larger values of E η and Δ μ 2 0 ≠ - Δ μ 1 0 ≠ indicates that the movement of long chain salts is more difficult in AN solutions. To understand ion and solvent interactions in new electrolyte systems is helpful to promote their commercial application. Abstract: The thermodynamic properties of electrolyte solutions play a great role in super- capacitors. However, the related fundamental properties and rules for new electrolyte solution systems are still scarce. Herein, the densities and viscosities of ethyltributylphosphonium tetrafluoroborate (EBPBF4 ), tetrabutylphosphonium tetrafluoroborate (TBPBF4 ), and hexyltributylphosphonium tetrafluoroborate (HBPBF4 ) in acetonitrile (AN) solutions was measured at temperature range from 293.15 to 323.15 K at atmospheric pressure. The apparent molar volumes, limiting apparent molar volumes, viscosity B-coefficient and some important parameters were also calculated, and used to discuss to ion-ion and ion-solvent interaction in studied systems. The values of d B/ d T in all studied solutions are negative indicating that hydrodynamic volume of ions is decreased by increasing temperature and indicating that all solutes as structure makers in AN medium. Furthermore, activation energy and the contributions of solute to the molar Gibbs energy of activation for the viscous flow of the solution are also discussed by Eyring transition state theory. These results will be helpful to further understand the ion-ion and ion-solvent interaction in new electrolyte systems and promote their design and commercial application.