Thermodynamics of the Cu+/Cu2+-redox equilibrium in soda-silicate and soda-lime-silicate melts

Thermodynamics of the Cu+/Cu2+-redox equilibrium in alumosilicate melts

“…In previous studies, the effect of glass composition on the Cu + /Cu 2+ -redox equilibrium was studied for soda-silicate and soda-lime-silicate [25,26]. For these glass compositions, up to a certain alkali or alkaline earth concentration (basicity), the Cu + /Cu 2+ -ratio increased and then remained constant.…”

“…Two peaks are observed. The peak at positive or less negative potentials is due to the reduction of Cu 2+ to Cu + and that one at more negative potentials is caused by the Cu + /Cu 0 -redox pair [26,27,29]. Both peaks are shifted to smaller potentials with decreasing temperature.…”

Formation and its mechanism of copper metal layers at surface by annealing in reduced atmosphere in CuO–Li2O–Nb2O5–SiO2 glass

“…For instance, Kaufmann and Russel [22,23] have studied the Cu + /Cu 2+ -redox equilibrium in Na 2 O-CaO-SiO 2 melts by using square-wave voltammetry and reported that the Cu + /Cu 2+ ratio increases first with increasing melt basicity and remains constant for optical bacisities Λ > 0.56. Their data indicate that the fraction of Cu + ions in the glasses with Λ > 0.56 are~60% [23].…”

“…It is of interest and of importance to clarify the bonding, coordination, and valence states of copper ions in Li 2 O-Nb 2 O 5 -SiO 2 glasses. Recently, Kaufmann and Russel [22,23] have reported the redox behavior and diffusion of copper ions in Na 2 O-CaO-SiO 2 melts.…”

Effects of composition on redox behaviors of antimony or arsenic ion in silicate melts by differential pulse voltammetry

“…This is the reason why electrochemical techniques developed in aqueous solution are applied to high-temperature glass melts. There are so many reports on redox states of multivalent ions in glass melts using cyclic voltammetry [8][9][10], square-wave voltammetry [2,[11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27], and differential pulse voltammetry [6,10,[28][29][30][31][32][33][34]. Among these papers, Rüssel and co-workers [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] reported the redox states, the equilibrium constants, and thermodynamic data of various types of multivalent ions in some glass melts by using square wave voltammetry.…”