Ultralow-Content Iron-Decorated Ni-MOF-74 Fabricated by a Metal-Organic Framework Surface Reaction for Efficient Electrocatalytic Water Oxidation
Ultralow-Content Iron-Decorated Ni-MOF-74 Fabricated by a Metal-Organic Framework Surface Reaction for Efficient Electrocatalytic Water Oxidation
复制标题
通过金属有机框架表面反应制备超低含量铁装饰的 Ni-MOF-74，用于高效电催化水氧化
DOI：
10.1021/acs.inorgchem.9b01301
复制
发表时间：
2019-09-02
影响因子：
4.6
通讯作者：
Luo, Feng
中科院分区：
文献类型：
--
作者：
Gao, Zhi;Yu, Zhi Wu;Luo, Feng
过渡金属-有机骨架（MOFs）因其成本低、有机官能团和金属中心多样而被认为是最具吸引力的电催化剂之一。不同于常用的调整多元mof中金属中心比例的策略，本文利用Fe2+与Ni-MOF-74表面羟基之间快速的“苯酚-铁（Fe）”表面反应，在单金属Ni-MOF-74表面装饰了超低含量的Fe2O3。利用这种灵活的方法，可以很好地调节铁的负载，从而制备出一系列不同铁含量的Fe修饰Ni-MOF-74。优化后的0.6 wt % Fe2O3 @Ni-MOF-74在含铁量为0.6 wt %的情况下，只需要264 mV的过电位就能输出10 mA cm(-2)，明显优于无铁Ni-MOF-74 （323 mV）和其他Fe2O3 @Ni-MOF-74，甚至优于商用IrO2基准（300 mV）。x射线光电子能谱结果表明，Fe修饰可以明显调节Ni- mof -74中Ni中心的电子结构，从而增强析氧反应活性。本研究为直接用于电催化工艺的mof基电催化剂的制备开辟了一条新的途径。
Transition-metal-organic frameworks (MOFs) have been regarded as one of the most intriguing electrocatalysts because of its low cost and diversity in functional organic groups and metal centers. Different from the common strategies of tuning the ratio of metal centers in multivariate MOFs, here, ultralow-content Fe2O3 is decorated on the surface of monometallic Ni-MOF-74 based on the fast "phenol-iron (Fe)" surface reaction between Fe2+ and the surface hydroxyl group in Ni-MOF-74. Benefiting from this flexible method, the Fe loading can be finely modulated and thus a series of Fe-decorated Ni-MOF-74 with different Fe contents are prepared. The optimized 0.6 wt % Fe2O3 @Ni-MOF-74 with the Fe loading of 0.6 wt % only needs the overpotential of 264 mV to deliver 10 mA cm(-2), which obviously outperforms Fe-free Ni-MOF-74 (323 mV) and other Fe2O3 @Ni-MOF-74 and is even superior to the commercial IrO2 benchmark (300 mV). X-ray photoelectron spectroscopy results disclose that Fe decoration can obviously modulate the electronic structure of Ni center in Ni-MOF-74, thereby resulting in enhanced oxygen evolution reaction activity. This work opens up a new avenue to fabricate excellent MOF-based electrocatalysts for direct utilization in an electrocatalytic process.