采用Hummers法合成了氧化石墨烯(GO),然后以三聚氰胺为前驱体,在马弗炉中热聚合合成石墨状氮化碳(g-C3N4),并将GO和三聚氰胺按不同质量比混合均匀后,采用同样方法制备一种全新的GO/g-C3N4复合光催化剂。通过X射线衍射、红外光谱和扫描电镜等手段对所制备的样品进行了表征。结果表明:引入GO不仅使 g-C3N4的大部分结构得到保留,而且没有改变g-C3N4的键合形式,但使g-C3N4表面出现了不规则孔洞和类球状颗粒,大大增大了g-C3N4的比表面积。在LED灯下用亚甲基蓝(MB)水溶液制样进行光催化活性评价,发现复合光催化剂的MB降解率均高于纯g-C3N4(6.41%),且1.00% GO/g-C3N4效果最好(21.84%),提升了3.41倍。最后探究了催化剂用量、温度和循环次数对复合光催化剂性能的影响。
The graphene oxide (GO) was synthesized by hummers method,and then melamine was used as a precursor to thermally synthesize graphitic carbon nitride (g-C3N4) in a muffle furnace.GO and melamine were mixed at different mass ratios.After homogenization,a new GO/g-C3N4 composite photocatalyst was prepared by the same method.The prepared samples were further characterized by XRD,FT-IR and SEM.The results shown that the introduction of GO maintained the bonding form and major structure of g-C3N4,but built irregular holes and spherical particles on its surface,thus greatly increased its specific surface area.The photocatalytic activity test indicated that the degradation rate of the photocatalyst on the methylene blue (MB) in aqueous solution was higher than that of pure g-C3N4 (6.41%) under the LED lamp,and 1.00wt.% GO/g-C3N4 possessed the highest efficiency (21.84%) with 3.41 fold increase.The influence of catalytic concentration,temperature and cycles were also investigated.
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