Synergetic Cobalt‐Copper‐Based Bimetal–Organic Framework Nanoboxes toward Efficient Electrochemical Oxygen Evolution

Abstract

The development of efficient oxygen electrocatalysts and understanding their underlying catalytic mechanism are of significant importance for the high‐performance energy conversion and storage technologies. Herein, we report novel CoCu‐based bimetallic metal–organic framework nanoboxes (CoCu‐MOF NBs) as promising catalysts toward efficient electrochemical oxygen evolution reaction (OER), fabricated via a successive cation and ligand exchange strategy. With the highly exposed bimetal centers and the well‐designed architecture, the CoCu‐MOF NBs show excellent OER activity and stability, with a small overpotential of 271 mV at 10 mA cm−2 and a high turnover frequency value of 0.326 s−1 at an overpotential of 300 mV. In combination of quasi in situ X‐ray absorption fine structure spectroscopy and density‐functional theory calculations, the post‐formed CoCu‐based oxyhydroxide analogue during OER is believed to account for the high OER activity of CoCu‐MOF NBs, where the electronic synergy between Co and neighbouring Cu atoms promotes the O−O bond coupling toward fast OER kinetics.

Ultrafast transformation of metal–organic frameworks into advanced oxygen evolution electrocatalysts with good universality and scalability

“…Moreover, the strong electronic interactions would effectively modulate the d-band center of metal sites by charge redistribution. 27,52 As shown in Fig. 4h, the d-band center of Co was calculated to be −1.56 and −1.48 eV for CoNiOOH and Fe–CoNiOOH, respectively.…”

“…Moreover, the strong electronic interactions would effectively modulate the d-band center of metal sites by charge redistribution. 27,52 As shown in Fig. 4h, the d effectively balance the interaction with OER intermediates by enhancing the binding property, especially facilitating the adsorption of *OH and simultaneously improving the OER activity (Fig.…”

“…Additionally, the high-temperature pyrolysis also imposes side-effects on the mechanical stability of OER electrodes resulting from the fragmentation of catalysts and degeneration of substrates. 26 Other strategies for ameliorating the OER performance of MOFs, including morphology regulation, 27 metal node modulation, 28 defect engineering, 29 and inducing lattice strain, 30 also involve either multiple tedious procedures or laborious treatments, which creates obstacles for fabrication of large-size electrodes. Therefore, to engineer MOF-based materials for boosting OER kinetics, developing facile, low-cost, and universal strategies that are suitable for large-scale adoption is highly desirable, which however remains a great challenge.…”

Research progress in improving the oxygen evolution reaction by adjusting the 3d electronic structure of transition metal catalysts

“…Cheng et al used continuous cation and ligand exchange strategies to prepare CoCu-based conductive bimetal MOF nanoboxes (NBs), containing M 1 -O x structures and Co/Cu bimetal sites with multiple metal valence states. 85 As an OER catalyst, the overpotential at 10 mA cm −2 is 271 mV and the high turnover frequency (TOF) at 300 mV is 0.326 s −1 , rendering these NBs one of the best MOF-based/derived OER electrocatalysts. This is mainly due to the electronic interaction of Co with the surrounding Cu atoms, which can promote the gene-ration of *OOH intermediates and O-O-bonding coupling at the active site, accelerating the OER dynamics.…”

Synergetic Dual‐Ion Centers Boosting Metal Organic Framework Alloy Catalysts toward Efficient Two Electron Oxygen Reduction

“…Moreover, bimetallic MOFs with similar 3d electronic configurations have been demonstrated to exhibit promising catalytic activity toward oxygen evolution, because of the optimized adsorption energetics of crucial intermediates over the synergetic transition metal cations. [26,27] However, the fabrication of dual transition-metal-based conductive MOFs toward efficient electrochemical two-electron ORR has been rarely reported. Thus, construction of Ni-based bimetallic MOF alloys catalysts, with unique 3d-3d synergetic centers, is an attractive approach to enable Ni-based MOFs with high catalytic activity and selectivity for H 2 O 2 generation during ORR.…”