Co_(3)O_(4)-SnO_(2)hybrid oxides were prepared by the coprecipitation method and were used to oxidate methane(CH4)in presence of oxygen.The Co_(3)O_(4)-SnO_(2)with a molar ratio of Co/(Co+Sn)at 0.75 exhibited the highest catalytic activity among all the Co_(3)O_(4)-SnO_(2)hybrid oxides.Experimental results showed that the catalysts were considerably stable in the CH4 combustion reaction,and were verified by X-ray photoelectron spectra(XPS).It was found that Co_(3)O_(4)was the active species,and SnO_(2)acted as a support or a promoting component in the Co_(3)O_(4)-SnO_(2)hybrid oxides.The surface area was not a major factor that affected catalytic activity.The hydrogen temperatureprogrammed reduction(H_(2)-TPR)results demonstrated that the interaction between cobalt and tin oxides accelerated the mobility of oxygen species of Co_(3)O_(4)-SnO_(2),leading to higher catalytic activity.
