Electrical double layer at alumina/electrolyte interface

Surface acid–base properties and hydration/dehydration mechanisms of aluminum (hydr)oxides

“…Rinsing with H 2 O and drying NaCl pK a1 = 4.9 ± 0.5, pK a2 = 11.3 ± 0.5 [46] at room temperature pK Na = 8.6 ± 0.1, pK Cl = 7.5 ± 0.1 Titration rate not given reduced. Jodin et al [26] also observed these hysteresis phenomena and explained them by the effect of the ionic strength and the solids not being at their point of zero charge at the end of the dialysis process.…”

The Nature of the Surface Charge of Kaolinite

“…Actual values of A~ used in the calculation are listed in Table 1. The charge densities of alumina (Sprycha, 1989b) and silica (Abendroth, 1970), as determined by cation exchange methods, are also shown in Figure 1B for comparison. The surface charge density of the edges of kaolinite is one of order magnitude greater than that of either alumina or silica in the same solution conditions.…”

“…However, our main concern is the surface charge density itself, and consequently the shape of the titration Figure 3. For comparison, the net surface proton charge densities of silica (Bolt, 1957) and alumina (Sprycha, 1989a) are also shown in Figure 3. The aH of the edges of kaolinite is an order of magnitude greater than that of either silica or alumina.…”

Template-Assisted Electrochemical Growth of Hydrous Ruthenium Oxide Nanotubes

“…26 A number of articles have reported that ions can be adsorbed on the surface of alumina. [27][28][29][30] Ru is a typical multivalent noble metal, with oxidation states ranging from −2 to +8. In this work, the most common precursor compound was RuCl 3 , which has an oxidation state of +3.…”