钴掺杂二氧化钛的光催化制氢性能
Photocatalytic Activity of Cobalt Doped Titania for H_2 Evolution
Abstract
采用聚合络合法(PCM)制备出钴掺杂二氧化钛(CO/TIO_2)光催化剂.以热重-差示扫描量热同步热分析(TgA-dSC),傅里叶变换红外(fT-Ir)光谱,X射线粉末衍射(Xrd),氮气吸附-脱附,紫外-可见漫反射光谱(uV-VIS drS),X射线光电子能谱(XPS)等手段对材料进行了表征.采用光催化制氧作为探针反应,以氧气的产量评价材料的光催化性能结果表明:采用聚合络合法制备的样品主体成分为锐钛矿晶型的二氧化钛,钴元素呈高度分散,钴的掺杂能够明显提升二氧化钛光催化材料的光催化制氢活性,当钴钛物质的量之比为0.3%时,催化剂具有最佳的光催化制氢活性,达到2499μMOl,是同等条件下制备的无掺杂二氧化钛的近六倍.还对钴离子掺杂增强机理进行了探讨. Cobalt-doped titania(Co/TiO_2) photocatalysts were synthesized by the polymerized complex method(PCM).The materials were characterized by thermogravimetric analysis-differential scanning calorimetry(TGA-DSC),Fourier transform-infrared spectroscopy(FT-IR),X-ray diffraction(XRD),nitrogen adsorption-desorption,ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS) and X-ray photoelectron spectroscopy(XPS).The photocatalytic activity of the samples was evaluated by hydrogen evolution.The results show that anatase type titania exists in the materials and cobalt is evenly dispersed.The activity of the cobalt doped titania was found to be superior to that of pure titania.The maximum activity obtained at 0.3%Co/Ti molar ratio was nearly 6 times as high as that of pure titania.The amount of hydrogen produced was up to 2499μmol.The doping mechanism of cobalt is discussed.