AgI/Ag_3PO_4异质结催化剂可见光催化还原CO_2的研究  

Photocatalytic reduction of CO_2 with AgI/Ag_3PO_4 heterojunction catalyst under visible light

作　　者：曾滔[1] 林海燕[1] 余岩 何志桥[1] 宋爽[1] ZENG Tao;LIN Hai-yan;YU Yan;HE Zhi-qiao;SONG Shuang(Colloge of Environment, Zhejiang University of Technology, Hangzhou 310032, China)

机构地区：[1]浙江工业大学环境学院,浙江杭州310032

出　　处：《中国环境科学》2017年第5期1751-1758,共8页China Environmental Science

基　　金：国家自然科学基金资助项目(21607130;21477117);中国博士后科学基金(2016M90548)

摘　　要：首先采用离子交换法制备了四面体Ag_3PO_4,然后在其表面通过沉淀法负载上AgI,形成AgI/Ag_3PO_4异质结催化剂.利用可见光催化还原CO_2考察了催化剂的活性及稳定性,同时研究了AgI与Ag_3PO_4的摩尔比对光催化活性的影响.结果表明,当AgI与Ag_3PO_4的摩尔比在30%时(AgI/Ag_3PO_4-30%),催化剂表现出最高的光催化活性,且CO_2的主要还原产物为CH_4.基于X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、比表面积测试(BET)和紫外-可见(UV-Vis)吸收光谱等表征结果,可以推断Ag_3PO_4和AgI之间形成的p-n异质结能有效分离光生电子和空穴,是催化剂高效活性的主要原因.Photocatalytic conversion of CO2into renewable hydrocarbons using solar energy is one of the potential solutions to both global warming and fuel crisis.Of particular interest in this work,we prepared AgI/Ag3PO4heterojunction catalyst as photocatalyst to convert CO2into value-added products.The synthesis route of AgI/Ag3PO4involved first ion-exchange preparation of tetrahedron Ag3PO4followed by precipitation of AgI.The samples were characterized by X-ray diffraction(XRD),scanning electron microscope(SEM),X-ray photoelectron spectroscopy(XPS),specific surface area test(BET),and ultraviolet-visible absorption spectra(UV-Vis).With the mole ratio of AgI/Ag3PO4being30%,the catalyst showed the best catalytic performance for reduction of CO2,and the major product was CH4.The pronounced photocatalytic performance should be attributed to the efficient separation of the light electrons and holes arisen from the p-n junction between Ag3PO4and AgI.

关 键 词：二氧化碳 催化还原 可见光 磷酸银 碘化银 异质结 

分 类 号：X13[环境科学与工程—环境科学] O643[理学—物理化学]