高效复合可见光催化剂Co-C_3N_4的制备及光催化性能研究

Co doped C_3N_4 Photo-Catalyst Preparation and its Properties in Photo-catalysis

以六水合氯化钴与三聚氰胺为前驱体,经改良制备方法获得一种高效率复合可见光催化剂Co-C_3N_4。通过XRD、XPS和TEM等对该催化剂的表面性质进行了表征分析。并以染料罗丹明B为模拟污染物进行了可见光催化降解研究,系统地研究了Co掺杂量对光催化速率的影响,对相关的光催化剂氧化机理进行了推理。结果表明,m(Fe)∶m(g-C_3N_4)=1%时,制备的Co掺杂g-C_3N_4表现出最佳的光催化性能,45min内罗丹明B的降解率高达95.7%。Co的掺杂是以二价阳离子形式结合于C_3N_4的表面,形成了全新的异质结结构。异质结的形成降低了C_3N_4晶体的带隙能,提高了C3N4对可见光的吸收,抑制了光生电子空穴对的复合,从而提高了C_3N_4的光催化性能。

With CoCl2· 6H2O and melamine as precursor, improved the original C3N4 preparation methods for making composite photocatalyst Co-C3N4.The crystal phase and morphology of C0-C3N4 were investigated by XPD XPS SEM and so on.To dye rhodamine B as model compounds to the degradation of rhodamine B as the probe, systemic study the effect of Co doping amount of light catalytic rate, the light catalytic oxidation mechanism of the related reasoning.The results show that the m （Fe） /m （g-C3N4） =1%, the preparation of Co doping g-C3N4 showed best photocatalytic performance, the degradation of rhodamine B within 45 min rate as high as 95.7%.Co doping in the form of bivalent cation combined with the surface of C3N4, formed a new heterojunction structure.The formation of heterojunction can reduce the band gap of C3N4 crystal, improved C3N4 to visible light absorption, inhibited the light pair of composite, so as to improve the photocatalytic performance of C3N4.