Ni_3Fe层状双羟基化合物的水热合成与电化学产氧催化性能研究

Hydrothermal Synthesis and Electrochemical OER Performance of Ni_3Fe-LDH

以硝酸盐为原料,采用一步水热法,调控反应过程中的蒸汽压,制备了不同尺寸和结晶性的Ni_3Fe层状双羟基化合物(Ni_3Fe-LDH)产氧催化剂。通过粉末X射线衍射(XRD)和透射电子显微镜(TEM)对合成的Ni_3Fe-LDH进行表征,发现合成过程中的高压促进Ni_3Fe-LDH晶格中Fe的掺入,造成LHD的平面尺寸显著增大、{003}晶面间距显著增加、同时{003}晶面的堆垛更加无序。通过三电极电化学测试,发现低压下合成Ni_3Fe-LDH在10 mA/cm2的电流密度下过电势仅为290 mV,优于高蒸气压合成的Ni_3Fe-LDH,且具有良好的电化学稳定性。

Ni3Fe layered double hydroxides (LDH) with different crystallinity were prepared by one-step hydrothermal method using nitrate precursors under different vapor pressures. The synthesized Ni3Fe-LDH was characterized by powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). It's found that high vapor pressure was favorable for the incorporation of Fe in the Ni3Fe-LDH crystal lattice, leading to increased lateral size and larger interlayer spacing. Through a three-electrode electrochemical test, it was found that the overpotential of Ni3Fe-LDH synthesized under low vapor pressure was only 290 mV at a current density of 10 mA/cm^2, which was superior to Ni3Fe-LDH synthesized under high vapor pressure.