纳米八面体形FeP@PC的制备及催化析氢性能

Preparation of UIO-66-based Porous Nano-octahedral FeP@PC for Efficient and Durable Hydrogen Evolution

以UIO-66为载体,经过FeCl3化学气相沉积、原位碳化和磷化及HF刻蚀等步骤制备了多孔FeP@PC催化剂.利用X射线衍射仪、场发射透射电子显微镜、 X射线光电子能谱仪和气体吸附仪等对催化剂的结构、形貌和比表面积等进行了表征;同时采用线性扫描伏安法和电化学阻抗谱等对其电化学性质进行了考察.结果表明, FeP@PC保持了原UIO-66的八面体多孔结构,比表面积为83 m2/g;仅需要过电位156 mV即可驱动电流密度10 mA/cm^2,塔菲尔斜率为84 mV/dec,电荷转移电阻为44Ω,电化学活性表面积为13.9 mF/cm^2;在持续电解12 h和循环1000次后,催化剂的活性几乎没有衰减.

By using UIO-66 as the precursor, porous FeP@PC was prepared by chemical vapor deposition of FeCl3, in-situ carbonization, phosphating and HF etching. The morphology, crystal structure, elemental composition and valence states of FeP@PC were characterized by field emission transmission electron microscopy(FETEM), X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and N2 adsoption-desorption measurements. The results showed that FeP@PC maintained the original porous nano-octahedral structure of UIO-66 and had a high specific surface area of 83 m^2/g. For linear sweep voltammetry and electrochemical impedance spectroscopy measurements, the catalyst FeP@PC only needed overpotential of 156 mV to driven current density of 10 mA/cm^2. Meanwhile, the Tafel slope, the electron-transfer resistance and the electrochemically active surface area of the catalyst were calculated to be 84 mV/dec, 44 Ω and 13.9 mF/cm2, respectively. In order to evaluate the durability and stability of the catalyst, 12 h-chronoamperometry and 1000-cycle cyclic voltammetry measurements were also conducted and no obvious activity decay was observed.