Influence of sulfation on electron-acceptor properties of ZrO2 surface

Surface electron-acceptor properties of pure and sulfated zirconium dioxide are studied by EPR method. Sample modification by sulfate ions was carried out through treatment by 0.5 M solution of H2SO4. Sample specific surface constituted 130 and 91 m2/g for ZrO2 and ZrO2-SO42- correspondingly. Zirconium oxide surface sulfation results in insignificant increase of electron acceptor centre concentration, causing electron density shift. Concentration of centres capable of complex formation with complete charge transfer (CCT) on ZrO2-SO42- surface significantly exceeds the number of acceptor centres of the first type. Acceptor centres capable of CCT formation appear on the surface only after its modification by sulfate ions and probably essentially influence ZrO2-SO42- chemical properties