以磷钨酸(PTA)和SiC为原料,采用浸渍法制备了4种不同比例PTA的PTA-SiC光催化剂.采用紫外可见漫反射光谱、傅里叶红外变换光谱、X射线衍射光谱、扫描电镜进行表征,并以罗丹明B(RhB)为降解底物,考察光催化剂的光催化降解性能.结果表明,制备的光催化剂既保持了SiC的载体结构,又保持了PTA的Keggin型结构.PTA的质量分数40％的PTA-SiC光催化降解性能最好,在光照180 min时,RhB的降解率为66％,光降解反应速率常数为5.21×10-3min1.羟基自由基在光催化降解RhB中起决定作用的活性物质.

自2004年发现二维石墨烯以来,二维非金属材料因其丰富多样的性质受到广泛关注.该类材料具有极高的比表面积,可以作为光催化剂和电催化剂,为开发高效的可见光驱动的光催化材料提供了可能.该文综述了4种新型二维非金属材料:二维石墨烯、二维石墨相氮化碳、二维黑磷和二维氮化硼在光催化降解印染废水中的研究进展,并展望了未来的研究方向.

采用两步法制备了不同配比的BiVO4/C3 N4复合物,通过X-射线衍射(XRD)、扫描电子显微镜(SEM)和紫外可见-漫反射光谱(UV-Vis DRS)对BiVO4/C3 N4复合物进行了表征.研究了在氙灯照射下所有材料对罗丹明B的光催化降解性能.结果表明,Bi-C-100型BiVO4/C3 N4复合物的光催化降解能力最强,光照60 min时对罗丹明B的降解率达到82％;降解率达到纯BiVO4和纯C3 N4对罗丹明B的3.3倍和2.6倍.

Four kinds of x wt.% phosphotungstic acid/silicon carbide (PTA/SiC) photocatalysts were prepared by impregnation method with SiC, 12-phosphotungstic acid (PTA) as raw materials. The structure of samples was characterised by X-ray diffraction, ultraviolet–visible diffuse reflectance spectra, scanning electron microscope. The photocatalytic activity of samples was evaluated by the degradation of rhodamine B (RhB) under a xenon lamp (λ≥420 nm). The results indicate that the photocatalysts not only maintained the SiC structure but also kept the Keggin structure of PTA. The 20 wt.% PTA/SiC exhibited the best photocatalytic degradation efficiency reaching up to 77% for 180 min irradiation, and the photo-degradation rate constant was determined to be 7.82 × 10−3 min−1. In the presence of H2O2, the photocatalytic degradation rate of 20 wt.% PTA/SiC composites was increased to 87%, and the photodegradation reaction rate constant was 7.77 × 10−3 min−1. According to free radical trapping experiments, it is proved that hydroxyl radical (·OH) plays an important role in photocatalysis.