Influence of long-term aqueous exposure on surface properties of plasma-sprayed oxides Cr2O3 and Cr2O3-25 wt% TiO2.

Research paper by Mika M Harju, Mikael M Järn, Per P Dahlsten, Juha-Pekka JP Nikkanen, Jarl B JB Rosenholm, Tapio T Mäntylä

Indexed on: 05 Aug '08Published on: 05 Aug '08Published in: Journal of Colloid and Interface Science


The influence of water exposure on the surface properties of plasma-sprayed Cr(2)O(3) and Cr(2)O(3)-25 wt% TiO(2) was studied. It was shown that both plasma-sprayed materials contained Cr(VI) hydrous oxide phases, which dissolved rapidly at the beginning of water exposure. The dissolution continued slowly during the whole water exposure time. The Cr(VI) dissolution was accompanied by a rapid increase in surface IEP value. Both Cr(2)O(3) and Cr(2)O(3)-25 wt% TiO(2) showed similar dissolution, zeta potential, and surface oxidation states. Thus the addition of TiO(2) did not influence the surface properties of the plasma-sprayed Cr(2)O(3).