Metal–Organic Frameworks and Their Composites: Synthesis and Electrochemical Applications

Abstract

metal-oxo units) coordinating with electron-donating organic ligands. These hybrid materials have received broad concern because MOFs can be rationally synthesized with high porosities, large internal surface areas, uniform but adjustable pore sizes and structures. MOFs exhibit a tremendous growth, in terms of numerous structures, fascinating topological nets, and various application including gas storage and separation, [9][10][11][12][13][14][15][16][17][18][19][20][21] catalysis, [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] sensor, [38][39][40][41] drug delivery, [42,43] luminescence, [44,45] and others. [46][47][48][49][50][51][52][53][54][55][56][57][58][59][60] Apart from these applications, in recent years, there is an increasing interest in discovering the electrochemical applications in the field of supercapacitors, batteries and fuel cells, hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR), electrochemical decomposition of highly oxidizing and toxic compounds, electrochemical sensors, etc.In view of the ever-growing energy demand as well as the increasing serious environmental crisis caused by the combustion of traditional fossil fuels, the pursuit of renewable energy sources resorting to the sunshine and wind, along with storage technologies, has always been a hot research subject. The intermittent feature of solar and wind sources limits their applied range, thus the effective energy storage technology is becoming a tremendous need to put electronic equipment into operation and provide electrical transportation power for commuters. Energy storage resorting to electrochemistry is thought to be one of the most promising candidates for energy storage. MOFs possess their particular advantages, in comparison with other types of porous materials including active carbon, zeolites. By selecting different metal ions and organic bridging linkers, MOFs constructed can meet the requirements of particular application through the predesign and postsynthesis methods. Various MOFs and MOF composites have been successfully used in the electrochemical areas. Moreover, MOFs as the sacrificial materials have been converted to various nanostructures, such as porous carbon, metal nanoparticles, metal oxides, and their composites with different treatments. These nanostructures with the maximum exposure of active sites inherit high surface area of MOF precursors to some extent and exhibit good performance as electrodes. For MOF-derived nanoporous functional materials, a number of reviews [61][62][63][64][65][66][67] and reports [68][69][70][71][72][73][74][75][76][77][78][79][80][81] have been published, which provided As a youthful family of crystalline porous materials, metal-organic frameworks (MOFs), assembled by inorganic vertices (metal ions or clusters) and organic ligands, feature ultrahigh porosity, high surface area, and synthetic and structural tailorability, along with relatively easy synthesis, making them excellent candidates for a large ...

Metal–Organic Frameworks Encapsulating Active Nanoparticles as Emerging Composites for Catalysis: Recent Progress and Perspectives

“…To date, many strategies have been applied to engineer the electrical conductivity of MOFs, and significant progress has been achieved . Gándara et al described a series of metal‐triazolate MOFs, and one of them exhibited ohmic conductivity that was highly specific to the presence of Fe(II) in the structure .…”

Metal–Organic Frameworks and Their Derived Materials as Electrocatalysts and Photocatalysts for CO2 Reduction: Progress, Challenges, and Perspectives

“…[79] In addition, MOFs with differentmorphologies could be used for photocatalytic and electrocatalytic CO 2 reductions. Because of the tunable metal nodes and organic ligandso fM OFs along with many feasible methods to prepare MOF-derived materials, the MOF-based electrocatalysts and photocatalystse xhibit great promise to boost the performance of CO 2 reduction reactions.…”

“…In this sense, the modification of MOFbased materials could be performed by tuning the metal nodes and organic struts,w hich can induce different properties to the as-prepared materials. [79] In addition, MOFs with differentmorphologies could be used for photocatalytic and electrocatalytic CO 2 reductions. These unique morphologies such as nanosheets, nanoflowers, and three-dimensional ordered structures can enhancet he mass transfer and the light absorbance through multiple reflectiono rs low photon effects.…”

Metal‐Organic Frameworks/Graphene‐Based Materials: Preparations and Applications

“…Nevertheless, what cannot be ignored is that MOFs still have some defects, which restrict their applications to a great extent. For instance, MOFs exhibit inferior performance at electrically conduction and have a poor ability of stability, preventing them from demonstrating their best performance in the field of electrochemistry . Encouragingly, there comes out an idea of assembling MOFs with other materials to generate a MOF‐based composite, which can combine the advantages of both parent materials.…”