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摘要
以磷酸钠、磷酸铵为磷源,以三聚氰胺为石墨相氮化碳(g-C3N4)前驱体,制备磷掺杂的类石墨相氮化碳(P-CN),探索最优的掺杂制备条件如:磷源选取、掺杂制备温度、合成方法和掺杂比例等。通过X射线衍射仪、紫外-可见漫反射光谱仪、X射线光电子能谱仪、红外光谱仪、荧光光谱仪、透射电镜和扫描电镜等手段对样品进行表征分析,以罗丹明B为降解用污染物测试样品的光催化活性。结果表明:磷元素的掺入抑制了催化剂晶粒的生长,拓宽了样品的可见光响应范围,提高了对可见光的利用率,明显减小了样品的能带宽度,有效抑制了光生电子-空穴的复合,因此显著地提高了样品的光催化性能。且不同掺磷量的样品中P-CN(1∶8)的光催化活性最高,其光催化降解罗丹明B的速率常数是纯g-C3N4的38倍。
Abstract
Phosphorus doping graphitic carbon nitride(P-g-C3N4) with sodium phosphate and ammonium phosphate as phosphorus source,and melamine as precursor of g-C3N4.The optimum preparation conditions such as phosphorus source selection,doping preparation temperature,synthesis method,doping ratio and so on were explored.The samples were characterized by XRD,UV-Vis,XPS,FT-IR,PL,TEM and SEM.The photocatalytic activity of the samples was tested with rhodamine B as the degradation pollutant.The results shown that:the doping of phosphorus inhibited the growth of catalyst grain,broadened the response range of visible light,improved the utilization of visible light,obviously reduced the bandgap width of the sample,effectively suppressed the recombination of photogenerated electrons and holes.So the photocatalytic properties of the samples were improved significantly.And the photocatalytic activity of P-CN(1∶8) was the highest among the samples with different phosphorus content,its rate constant of photocatalytic degradation of rhodamine B was 38 times of pure g-C3N4.
关键词
石墨相氮化碳
/
光催化
/
掺杂
/
罗丹明B
Key words
graphitic carbon nitride
/
photocatalysis
/
doping
/
rhodamine B
磷掺杂石墨相氮化碳及其光催化性能研究[J].
化工新型材料, 2020, 48(4): 196-201 DOI:
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