g-C_(3)N_(4)/Bi/Bi_(2)WO_(6)光催化材料的协同改性研究

Study on synergistic modification of g-C_(3)N_(4)/Bi/Bi_(2)WO_(6) photocatalyst

以五水合硝酸铋[Bi(NO_(3))_(3)·5H_(2)O]为铋源、二水合钨酸钠(Na_(2)WO_(4)·2H_(2)O)为钨源通过水热法制备出多孔钨酸铋(Bi2WO6),并以纳米板条堆叠形成椭球结构的类石墨相氮化碳(g-C_(3)N_(4))为基底通过溶剂热法在原位还原金属铋(Bi)的同时制备出具有Z型异质结构的g-C_(3)N_(4)/Bi/Bi_(2)WO_(6)(CN/B/BWO)复合光催化材料。采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、氮气吸附-脱附等温线(BET)、紫外-可见吸收光谱(UV-Vis)和光致发光(PL)光谱等检测手段对制备的样品进行了表征。结果表明,金属铋可以作为类石墨相氮化碳和钨酸铋之间的电荷转移媒介,其产生的表面等离子体共振(SPR)效应可协同增强光生电子-空穴对的分离效率和载流子的迁移率,从而提升样品的光催化活性。采用350 W氙灯照射30 min,样品CN/B/BWO-0.7对盐酸四环素(TC-H)的降解率达到99.94%,并对其降解机理进行了探讨。

By using Bi(NO_(3))_(3)·5H_(2)O as the bismuth source and Na_(2)WO_(4)·2H_(2)O as the tungsten source,porous Bi_(2)WO_(6) was prepared by hydrothermal method,and g-C_(3)N_(4)/Bi/Bi_(2)WO_(26)(CN/B/BWO)composite photocatalyst with Z-type heterostructure was prepared by solvothermal method with g-C_(3)N_(4) with ellipsoidal structure formed by stacking nano strips as substrate and in situ reduction of metal Bi.The prepared samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen adsorption desorption isotherm(BET),ultraviolet visible absorption spectrum(UV-vis)and photoluminescence spectrum(PL).The results showed that the metal Bi could be used as the charge transfer medium between g-C_(3)N_(4) and Bi_(2)WO_(6).The surface plasmon resonance(SPR)effect generated by metal Bi could synergistically enhance the separation efficiency of photogenerated electron‑hole pairs and the mobility of carriers,thereby improving the photocatalytic activity of the samples.Under the irradiation of 350 W xenon lamp for 30 min,the degradation rate of tetracycline hydrochloride(TC-H)by sample CN/B/BWO-0.7 was 99.94%,and the degradation mechanism was discussed.