Zr–Al共掺对ZnO光催化剂结构和催化性能的影响

利用水热处理结合焙烧的方法分别制备了Zr、Al掺杂及Zr–Al共掺的ZnO光催化剂。研究了制备的光催化剂样品的相结构和光谱性能;以紫外光(λ=254nm)为光源,酸性橙Ⅱ为降解对象,进行光催化活性测试;考察了Zr、Al掺杂对ZnO光催化剂反应活性的影响。研究表明,制备的产物均为六方晶系纤锌矿结构的ZnO;Zr、Al掺杂及Zr–Al共掺的ZnO样品的光催化活性相对于纯ZnO均有较大程度的提高,而且Zr–Al共掺的ZnO的光催化性能明显优于单一掺杂的。Zr–Al共掺可以明显改善ZnO表面状态,使ZnO具有更丰富的表面羟基,同时可以抑制光生电子–空穴对的复合,从而有利于光催化活性和稳定性的提高。

Effect of Zr-Al Co-Doping on Structure and Photocatalytic Performance of ZnO Photocatalyst

Zr-doped, Al-doped, and Zr–Al co-doped ZnO photocatalysts were prepared via a hydrothermal synthesis method and subsequent calcination treatment. The structure and spectral properties of the prepared photocatalysts were investigated. The photocata- lytic activity of the prepared catalysts was evaluated by the photocatalytic degradation of acid orangeⅡunder an ultraviolet light (λ = 254 nm) irradiation. The results show that the products prepared are a hexagonal wurtzite structure of ZnO. Compared to pure ZnO, the photocatalytic activity of Zr-doped, Al-doped, and Zr–Al co-doped ZnO photocatalyst samples had a greater improvement, and the photocatalytic performance of the Zr–Al co-doped ZnO was significantly better than that of Zr or Al-doped ZnO. The increased photocatalytic activity for the Zr–Al codoped ZnO sample could be attributed to that the Zr–Al co-doped ZnO photocatalyst had the more OH groups on the surface of doped sample than the pure ZnO. The co-doping could effectively suppress the recombination of photo-generated electron–hole pairs, thus favoring the improvement of photocatalytic activity and stability of ZnO.