仿生钛化法制备TiO_(2)-Cu-AC复合光催化剂

Preparation of TiO_(2)-Cu-AC Composite Photocatalyst by Biomimetic Titanification

以海藻为碳源,采用KOH研磨-熔融活化法制备了比表面积2190 m^(2)/g的海藻基活性炭(AC),并利用仿生钛化的方法实现TiO_(2)纳米粒子在AC表面原位生长。进一步复合铜离子获得TiO_(2)-Cu-AC复合光催化剂,用于可见光照射条件下的污染物催化降解。表征结果显示,复合材料中AC、Cu^(2+)与TiO_(2)紧密结合在一起,可见光区吸收较纯TiO_(2)明显增强,禁带宽度降低到2.38 eV,电子-空穴的复合得到了有效抑制。与纯TiO_(2)纳米颗粒相比,TiO_(2)-Cu-AC在可见光照射下降解污染物模型分子罗丹明B的一级反应速率常数是其12.6倍,90 min降解率接近100%。

Using alga as the raw material,the alga-based activated carbon(AC)with a specific surface area of 2190 m^(2)/g was prepared through the KOH grinding-melting activation method.The biomimetic mineralization method was used consequently to complete the in-situ growth of TiO_(2)nanoparticles on the AC surface,and the copper ions were further added to synthesize the TiO_(2)-Cu-AC composite photocatalyst for the catalytic degradation of pollutants under visible light irradiation.The characterization results showed that the AC,Cu^(2+)and TiO_(2)in the composite material are closely combined,the visible light region absorption is significantly enhanced compared to pure TiO_(2),the forbidden band width drops to 2.38 eV,and the fluorescence emission efficiency decreases,indicating that the electron-hole recombination is effective reduced.The photocatalytic performance tests demonstrate that the first-order reaction rate constant of Rhodamine B degradation catalyzed by TiO_(2)-Cu-AC composite material under visible light irradiation reaches 12.6 times of that catalyzed by pure TiO_(2)nanoparticles,and the degradation efficiency after 90 min is close to 100%.