两种g-C3N4的异质结的第一性原理计算

摘要

运用第一性原理方法计算了两种新型的g-C3N4的异质结g-C3N4/TiO2和g-C3N4/MoS2,其带隙分别为1.281和0.344 eV,两者的带隙相比单层g-C3N4有所减小.两者的VBM主要由N2p电子构成,CBM主要由Ti或Mo3d电子构成,并且两者的HOMO和LUMO都出现了层分离,使得电子空穴复合速度下降,提高了光催化效率.%Heterojunctions g-C3N4/TiO2 and g-C3N4/MoS2 were studied by first principle calculation.The band gaps of g-C3N4/TiO2 and g-C3N4/MoS2 were 1.281 eV and 0.344 eV,which decreased in comparison with that of g-C3N4 single layer.Their VBM are comprised of 2p electron belong to N,while the CBM are mainly com-prised of 3d electrons belong to Ti or Mo.The HOMO and LUMO of heterojunctions detached from the layers, inducing lower recombination velocity of electrons and holes and improving the efficiency of photolysis.