Metal‐Organic Frameworks‐Derived Nickel–Iron Oxyhydroxide with Highly Active Edge Sites for Electrochemical Oxygen Evolution

Abstract

Understanding the structure-property relationship of catalysts is the key to designing and manufacturing catalysts with high chemical activity and durability. [1][2][3][4] Since the active sites on the surface of heterogeneous catalysts cannot be clearly defined and quantified in contrast to their homogeneous opponents, as a result, the blossom in the realm of heterogeneous catalysis is often hindered by the difficulty of identifying the active sites on the catalyst surface. [5][6][7][8][9] The situation becomes more complicated especially when the surface of catalysts featuring versatile potential active sites or multiple catalytical active sites cooperate to promote a transformation process. [10][11][12][13] Although many available in situ and ex situ experimental techniques along with computational methods have been developed to solve these puzzles, sometimes the clear and accurate identification of active sites on the catalysts is still a challenging task. [14][15][16][17][18] In addition, how to quantitatively graft the highly active catalytic sites to the certain lattice positions of the solid catalyst to achieve high-efficient catalysis is another huge challenge for rational design and synthesis of heterogeneous catalysts with excellent performance. [19][20][21] Metal-organic frameworks (MOFs) are an important class of inorganic-organic hybrid porous materials featuring the characteristics of the tailorable structure, easy characterization, high specific surface area, and adjustable pore size. [22,23] These advantages not only bestow MOFs with the potential to be high-performance catalysts, but also make them the ideal platform for studying the structure-property relationships. [24][25][26][27] Furthermore, highly active sites can be introduced into the specific lattice positions during the construction of MOFs-based catalysts by direct solvothermal synthesis or post-synthetic methods (including post-synthetic modification, post-synthetic protection, and post-synthetic exchange) to boost the catalytic activity. [28][29][30] However, the thermal or chemical stability of most MOFs under catalytic conditions is usually poor, which limits their practical application. [31,32] The mixed-nickel and iron oxide/oxyhydroxide (NiFeO x H y ) nanosheets are a kind of inorganic layered compound composed of main layer and interlayer anions, where the bivalent or trivalent nickel/iron ions in the main layer coordinate with anionic

Li–N2 Battery for Ammonia Synthesis and Computational Insight

“…Even with the high priority given to environmental issues, the HB process is still running and has long been considered for a century due to the irreplaceable role of ammonia . However, electrification of the chemical industry is the future trend of carbon emission reduction with the development of renewable energy. − …”