固相法制备PTh/TiO_2复合纳米粉可见光催化剂

Preparation of PTh/TiO_2 nanocomposite by solid-state method and its photocatalytic activity under visible light irradiation

利用Sol-gel法制备了TiO2纳米颗粒,然后以无水三氯化铁为氧化剂,室温固相氧化聚合噻吩,得到聚噻吩(Polythiophene,PTh)敏化纳米TiO2形成的PTh/TiO2复合纳米粉。以XRD、TEM、DRS等方法对其相组成、形貌及其光谱特性进行了研究。结果表明,所得纳米TiO2为纯锐钛矿晶型,平均颗粒尺寸为18 nm;PTh/TiO2复合物具有20×80 nm的棒状形貌;DRS中吸收限在605nm处。以甲基橙作为模型试验了产品的光催化性能,结果表明,在太阳光照射下,120 min时PTh/TiO2对甲基橙降解率达85.6%,光催化性能优于纯TiO2、PTh及商品Degussa P25 TiO2光催化剂。探讨了PTh促进TiO2光催化性能的机理。

TiO2 ,PTh and PTh/TiO2 nanopowders were prepared by Sol-gel and solid-state reaction method, respectively. The phase composition, shape and the spectral properties of the products were characterized. The photocatalytic activity was evaluated by the degradation of methyl orange under visible light. TEM result showed that PTh/TiO2 nanocomposite has a rod-like shape with 20 × 80 nm. DRS analysis indicated that the absorption edge of PTh/TiO2 was 605nm. Compared with unmodified TiO2 and bare PTh, PTh/TiO2exhibited largely enhanced activity for photocatalytic degradation of methyl orange under visible light irradiation. The degradation rate of methyl orange of 85.6% could be obtained within 120 min. The mechanism of PTh promoted photocatalysis was discussed simply.