超细氧化钨的制备及其光催化性能研究
Preparation and photocatalytic performance of ultrafine tungsten oxide
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摘要: 以钨酸钠和盐酸为原料,碳纳米管为载体,采用一步法将钨酸颗粒直接沉积在碳纳米管管壁上,形成钨酸-碳纳米管(H2WO4-CNTs)复合物.或采用二步法将钨酸沉淀与碳纳米管复合,形成H2WO4-CNTs复合物.之后,在氧气气氛下进行煅烧,生成了氧化钨粉末.经物理性能测试,2种方法制备的H2WO4-CNTs复合物中钨酸颗粒的平均粒径分别为10 nm和100 nm.氧化钨粉末的平均粒径分别为250 nm和2 μm,比表面积分别为36.53 m2/g和13.99 m2/g.采用紫外可见分光光度计测定了氧化钨的光催化性能,在11 W的日光灯照射下,当光照时间为30 min时,脱色率分别达到93.8 %和79.1 %.结果表明,一步法制备的氧化钨因具有更小的平均粒径和更大的比表面积,表现出更好的物理吸附性能和光催化性能.Abstract: Sodium tungstate and hydrochloric acid are used as raw materials, carbon nanotubes as template, tungsten acid and carbon nanotube composite are prepared respectively by using one-step and two-step method, and then roasted at 600 ℃ for 2 h under oxygen atmosphere. The average particle size of tungsten acid and carbon nanotubes composite prepared one and two step methods are 10 nm and 100 nm respectively. The average particle size of tungsten oxide powders are 250 nm and 2 μm respectively. The specific surface area of tungsten oxide powders is 36.53 m2/g and 13.99 m2/g respectively. The photocatalytic performance of tungsten oxide is studied by the UV-Vis spectrophotometer using 11W fluorescent light as the light source. The degradation rate of tungsten oxide powders can reach 93.8 % and 79.1 %. The physical absorption and photocatalytic activity of tungsten oxide prepared by one-step method is better than that of two-step method because of its smaller particle diameter and higher specific surface area.