冬瓜基含TiO2炭气凝胶的制备、表征及其光催化性能

以冬瓜和钛酸四丁酯为原料，采用水热法和冷冻干燥法成功制备出含TiO₂炭气凝胶（WTCA），研究了其对罗丹明B废水的光催化降解性能，并考察了水中常见无机盐离子对其光催化效果的影响。利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、拉曼光谱仪（Raman）和荧光光谱仪（FL）等对样品结构和性能进行了表征。XRD、Raman和EDS分析表明复合气凝胶中含有锐钛矿TiO₂和碳元素；SEM和TEM分析表明TiO₂纳米颗粒均匀地负载在具有多级孔洞结构的炭气凝胶的骨架表面；含TiO₂炭气凝胶的光催化活性明显高于纯TiO₂，当负载量达30%时，其对罗丹明B的光催化降解效率最高（降解率达96.11%）。此外，无机盐阴离子对复合气凝胶的光催化效果有一定的抑制作用（CO₃^2- > SO₄^2- > Cl^- > NO₃^-），而无机盐阳离子Na⁺、K⁺、Ca²⁺和Mg²⁺的抑制作用不明显。

Preparation,Characterization and Photocatalytic Property of Wintermelon-based TiO2 Carbonaceous Aerogels

Wintermelon-based TiO₂ carbonaceous aerogel(WTCA) composites were prepared by hydrothermal reaction and freeze drying process with wintermelon and tetrabutyl titanate as precursor. The Rhodamine B(RhB) wastewater was photodegraded by WTCA under visible light irradiation. The effects of various common inorganic salt ions in water on the photodegradation were also studied systematically. The morphology structure and properties of as-prepared samples were characterized by using X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Raman spectrometer,and fluorescence spectroscopy(FL). XRD,Raman and EDS analysis results showed that anatase titanium oxide and carbon element appeared in the WTCA. SEM and TEM analysis results showed that TiO₂ nanoparticles were homogeneously anchored on the skeleton surface of hierarchical carbonaceous aerogels. Meanwhile the composite aerogels exhibited better photodegradation capacities for the RhB than pure TiO₂. The photocatalytic effect of WTCA had the best photocatalytic efficiency(96.11%) when TiO₂ load up to 30%. Moreover,the inorganic salt anion ions had the negative effect on photodegradation effect with the order of CO₃^2- > SO₄^2- > Cl^- > NO₃^- while the inhibitory effects of cationic ions(Na⁺,K⁺,Ca²⁺ and Mg²⁺) were not obvious.