Interfacial Fe−O−Ni−O−Fe Bonding Regulates the Active Ni Sites of Ni‐MOFs via Iron Doping and Decorating with FeOOH for Super‐Efficient Oxygen Evolution

Abstract

The integration of Fe dopant and interfacial FeOOH into Ni-MOFs [Fe-doped-(Ni-MOFs)/FeOOH] to construct FeÀ OÀ NiÀ OÀ Fe bonding is demonstrated and the origin of remarkable electrocatalytic performance of Ni-MOFs is elucidated. X-ray absorption/photoelectron spectroscopy and theoretical calculation results indicate that Fe-OÀ NiÀ OÀ Fe bonding can facilitate the distorted coordinated structure of the Ni site with a short nickel-oxygen bond and low coordination number, and can promote the redistribution of Ni/Fe charge density to efficiently regulate the adsorption behavior of key intermediates with a near-optimal d-band center.Here the Fe-doped-(Ni-MOFs)/FeOOH with interfacial FeÀ OÀ NiÀ OÀ Fe bonding shows superior catalytic performance for OER with a low overpotential of 210 mV at 15 mA cm À 2 and excellent stability with � 3 % attenuation after a 120 h cycle test. This study provides a novel strategy to design high-performance Ni/Fe-based electrocatalysts for OER in alkaline media.

Anchoring Ce-modified Ni(OH)2nanoparticles on Ni-MOF nanosheets to enhances the oxygen evolution performance

“…The cross-linked structure provides transport channels for electrolyte ions and rich surface areas for the anchoring nanoparticles. 32,33 After electrodeposition treatment, small nanosheets deposit on the Ni-MOF nanosheets in Ce(OH) 3 @Ni-MOF (Fig. S2c and d †); floc covers the Ni-MOF nanosheets in Ni(OH) 2 @Ni-MOF (Fig.…”

“…[5][6][7][8] Metal-organic frameworks (MOFs) have received widespread attention due to their high specific surface area and rich metal activity centers. [9][10][11][12] Relying on its own advantages, researchers modified Ni-MOFs by a variety of strategies to optimize the OER performance, such as designing the ultra-thin MOF nanosheet structure, 13,14 introducing heterogeneous atoms, and constructing heterostructures. [15][16][17][18] Therein, heterostructures can increase the contact interface/surface and enhance charge transfer, leading to improved OER activities, 19 such as MnCo 2 O 4 /CeO 2 , 20 CeO 2 -CoS 1.97 , 21 and CoP/CeO x .…”

An efficient vanadium/cobalt metaphosphate electrocatalyst for hydrogen and oxygen evolution in alkaline water splitting

“…9,22,[25][26][27] The transition metal based catalytic materials can form more active metal-oxo/hydroxo during the electrochemical processes, and the electronic structure of the transition metal surface is easier to optimize using a variety of strategies. [28][29][30][31][32] The chemical reaction process on the surface of transition metal compounds is more complex. Although molecular dynamics studies on the kinetic process of an electrochemical reaction on the surface of catalysts have not obtained exact results, it is generally believed that transition metal atoms are the major active sites of catalysts.…”

Exceptional Catalytic Activity of Oxygen Evolution Reaction via Two-Dimensional Graphene Multilayer Confined Metal-Organic Frameworks

“…based materials are known to exhibit high electrocatalytic activity towards OER, however, the easy change of the number and location of active sites for transition-metal oxides, hydroxides, oxyhydroxides and their derivatives is hard to alleviate. [9][10][11][12] Recently, metal-organic frameworks (MOFs) emerged as promising candidates for OER electrocatalysts owing to their large surface area, tunable porosity, as well as diverse compositions and metal centers. 11,13 Despite numerous MOF materials have been developed to catalyze OER, some essential issues remain to be solved.…”