银量子点修饰的氮化碳及其光解水产氢性能研究

Study on carbon nitride modified by silver quantum dots for photocatalytic hydrogen evolution

将尿素与乙酸银的混合物进行一步煅烧,得到了纳米尺度的银量子点(Ag QDs)修饰的氮化碳。用X射线衍射(XRD)、能谱(EDS)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)表征所得产物。结果表明,在CN100样品中,Ag QDs的大小约为5~7 nm,高度分散在氮化碳纳米片上。在光催化的过程中,Ag QDs不仅作为产氢助催化剂,而且能够快速捕获光生电子,从而显著提升体系的电荷传递和分离效率。产物CN100的光催化分解水产氢速率达到了215μmol h^(-1) g^(-1),约为纯氮化碳的60倍。

Carbon nitride modified by nano-sized silver quantum dots(Ag QDs)photocatalysts were prepared by a one-step calcination method using a mixture of urea and silver acetate.The as-prepared samples were characterized by X-ray diffraction(XRD),energy dispersive X-ray spectroscopy(EDX),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).For the obtained CN100 sample,the size of Ag QDs was 5~7 nm and they dispersed on the carbon nitride nanosheets well.In the photocatalysis process,Ag QDs not only act as H_(2) evolution promoter,but also quickly capture photogenerated electrons,thereby significantly improving the charge transfer and separation efficiency of the system.The photocatalytic H_(2) evolution rate of CN100 was up to 215μmol h^(-1) g^(-1),which is about 60 times that of pristine carbon nitride.