Fe^(3+)协同Ni基金属-有机框架提升电催化析氧反应活性的研究

Study on collaborative strategy between Fe^(3+)and Ni-based metal⁃organic frameworks for boosting electrocatalytic oxygen evolution

采用溶剂热法合成了金属-有机框架材料(phen-Ni),然后通过掺杂异金属Fe^(3+)制备了Fe@phen-Ni电催化剂。利用X射线单晶衍射仪、X射线光电子能谱仪、扫描电子显微镜和透射电子显微镜等对催化剂的物相、形貌及各成分化学状态进行表征。利用线性扫描伏安法(LSV)和电化学阻抗谱(EIS)等研究了Fe@phen-Ni催化剂的电催化析氧(OER)性能。结果表明,当电流密度为10mA/cm^(2)时,Fe@phen-Ni的OER过电位为333mV,与phen-Ni相比显示出更优异的OER催化活性。Fe@phen-Ni电催化活性的提高归因于Fe^(3+)的引入,这不仅增加了电催化剂的活性位点,而且由于Fe^(3+)和Ni^(2+)的协同作用,促进了电子转移,从而提高了电催化活性。该工作不仅证实了异金属离子的掺杂有利于提高电催化析氧活性,而且为基于金属-有机框架材料制备电化学OER催化剂提供了新的思路。

The metal-organic framework materials(phen-Ni)were synthesized by solvothermal method,and then Fe@phen-Ni electrocatalys were prepared by doping heterometallic Fe^(3+).The morphology,crystal structure and chemical composition of Fe@phen-Ni were characterized by X-ray single crystal diffractometer,scanning electron microscope(SEM),transmission electron microscope(TEM)and X-ray photoelectron spectrometer(XPS).The electrochemical oxygen evolution reaction(OER)activity of Fe@phen-Ni was investigated by linear sweep voltammetry(LSV)and electrochemical impedance spectroscopy(EIS).The results exhibited that Fe@phen-Ni had more excellent electrocatalytic performance with an overpotential of 333 mV at the current density of 10 mA/cm^(2) when compared with that of phen-Ni.The improvement could be attributed to the two factors.The introduction of Fe^(3+)increased the active site of the electrocatalyst.The synergistic action of Fe^(3+)and Ni^(2+) promoted the electron transfer.This work not only confirmed that doping of Fe^(3+)was beneficial to improve the electrocatalytic oxygenevolution activity,but also provided a new idea for the preparation of electrocatalytic OER catalysts based on metalorganic frame materials.