Z型Ag-Cu_(2)O/BiVO_(4)光催化剂的光催化还原CO_(2)性能

Photocatalytic CO_(2) reduction performance of Z⁃scheme Ag⁃Cu_(2)O/BiVO_(4) photocatalyst

利用简单的化学还原沉积法将Cu_(2)O纳米球和Ag纳米颗粒均匀包裹在十面体BiVO_(4)表面,成功构建了一种具有高效电荷载流子分离/转移特性的Z型异质结光催化剂Ag-Cu_(2)O/BiVO_(4)。Ag-Cu_(2)O/BiVO_(4)在可见光下光催化CO_(2)还原为CO的产率可达5.37μmol·g^(-1)·h^(-1),分别是纯BiVO_(4)和Cu_(2)O的35.8倍和6.25倍。通过X射线粉末衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、X射线能谱(EDS)、紫外可见漫反射光谱(UV-Vis DRS)、光致发光(PL)光谱、瞬态光电流响应(TPC)和电化学阻抗谱(EIS)对Ag-Cu_(2)O/BiVO_(4)的晶体结构、形貌、组成、能带结构和吸光能力等进行了系统表征分析,并提出了其光催化体系还原CO_(2)的催化机理。

A Z‐scheme heterojunction photocatalyst Ag‐Cu_(2)O/BiVO_(4) was successfully constructed with effective charge carrier separation/transfer by uniformly encapsulating Cu_(2)O nanospheres and Ag nanoparticles on the surface of decahedral BiVO_(4) using a simple chemical reduction deposition strategy.The photo‐reduction of carbon dioxide reaction result indicated that the as‐prepared Ag‐Cu_(2)O/BiVO_(4) heterostructure exhibited excellent activity of photo‐reduction CO_(2) with the CO yield of 5.37μmol·g^(-1)·h^(-1),about 35.8 times and 6.25 times of original BiVO_(4) and Cu_(2)O,respectively.Ag‐Cu_(2)O/BiVO_(4) was characterized by X‐ray diffraction(XRD),X‐ray photoelectron spectroscopy(XPS),scanning electron microscope(SEM),energy dispersive X‐ray spectroscopy(EDS),UV‐Vis diffuse reflectance absorption spectra(UV‐Vis DRS),photoluminescence(PL)spectra,transient photocurrent responses(TPC),and electrochemical impedance spectroscopy(EIS),and the possible reaction mechanism for the reduction of CO_(2) in the photocatalytic system was proposed.