通过热解法-化学剥离法制备层状结构的石墨相氮化碳(g-C3N4),进一步通过水热法制备了一系列不同质量比的二硫化钼/石墨相氮化碳(MoS2/g-C3N4)复合光催化剂。采用场发射扫描电子显微镜(SEM)和元素分布(mapping)分析、X射线衍射(XRD)以及紫外-可见吸收光谱(UV-Vis)对样品的微观结构和光学性能进行表征,在可见光照射下,研究光催化剂对有机染料的光降解性能以及光分解水产氢性能。结果表明:当光催化剂浓度为0.2g/L,可见光照射180min后,其对RhB和MB的降解率分别为78.8%和94.6%,反应常数分别是MoS2和g-C3N4的38.2倍和21.5倍。在可见光照射下,光催化分解水产氢的最高速率为151.4μmol/(g·h)。
The layered g-C3N4 was synthesized by pyrolysis-chemical stripping method,and a series of MoS2/g-C3N4 composite photocatalysts with different mass ratio were prepared by hydrothermal method.The microstructure and optical properties of the samples were characterized by field emission scanning electron microscopy (SEM),elemental mapping,X-ray diffraction (XRD),and UV-Vis absorption spectroscopy (UV-Vis).The photodegradation of organic dyes and photocatalytic split water for hydrogen production were studied under visible light irradiation.When the concentration of photocatalyst was 0.2g/L,the degradation rates of RhB and MB were 78.8% and 94.6% after 180min,and the reaction constants are 38.2 and 21.5 times than those of MoS2 and g-C3N4,respectively.The maximum rate of photocatalytic hydrogen evolution was 151.4μmol/(g·h) under visible light.
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