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Taking advantage of the self-assembling function of amino acids, cobaltalanine complexes are synthesized by straightforward process of chemical precipitation. Through a controllable calcination of the cobalt-alanine complexes, N-doped Co 3 O 4 nanostructures (N-Co 3 O 4 ) and N-doped CoO composites with amorphous carbon (N-CoO/C) are obtained. These N-doped cobalt oxide materials with novel porous nanostructures and minimal oxygen vacancies show a high and stable activity for the oxygen evolution reaction. Moreover, the influence of calcination temperature, electrolyte concentration, and electrode substrate to the reaction are compared and analyzed. The results of experiments and density functional theory calculations demonstrate that N-doping promotes the catalytic activity through improving electronic conductivity, increasing OH − adsorption strength, and accelerating reaction kinetics. Using a simple synthetic strategy, N-Co 3 O 4 reserves the structural advantages of micro/nanostructured complexes, showing exciting potential as a catalyst for the oxygen evolution reaction with good stability.

The purpose of this research is to develop an effective and inexpensive oxygen evolution reaction (OER) electrocatalyst to achieve high-efficiency water decomposition. Herein, Keggin-type polyoxometalate (POM) nanoparticles coated with zeolitic imidazolate framework (ZIF-67) were successfully synthesized by facile methods. An efficient ZIF-67@POM catalyst with yolk/shell structure is reported. The POM nanomaterials are uniformly dispersed in the surface of ZIF-67. This unique yolk/shell structure with potential synergistic interaction between POM and ZIF-67 results in superior electrocatalytic activity in OER. When the current density is 10 mA cm–2, the overpotential is only 287 mV, and the Tafel slope is 58 mV per decade. Moreover, the as-prepared yolk/shell ZIF-67@POM catalysts exhibit excellent cycling stability, high surface area, abundant surface active sites, and high diffusion efficiency comparable to the traditional noble-metal-free OER electrocatalyst.

With the ever increasing demand for clean, sustainable energy, electrochemical supercapacitors with the advantages of high power density, high efficiency and long life expectancy have become one of the major devices for energy storage and power supply, and have found wide application in hybrid power sources, backup power sources, starting power for fuel cells and burst-power generation in electronic devices.

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Pristine metal‐organic frameworks (MOFs) and their composites, which have received wide attention in recent years, especially in the field of electrocatalysis, are emerging as distinctive electrocatalysts for the oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO2RR), oxygen evolution reaction (OER), and many other electrochemical redox reactions. In this review, the attention is focused on the development of monometallic‐MOFs and multimetallic‐MOFs (including bimetallic‐MOFs and trimetallic‐MOFs) for electrocatalysis in recent years, including their design, catalytic performance and strategies for activity improvement. Finally, major challenges in utilizing pristine MOFs and their composites for electrocatalysis are highlighted.

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