Recent Approaches to Design Electrocatalysts Based on Metal–Organic Frameworks and Their Derivatives

Abstract

Rational design and synthesis of efficient electrocatalysts are important constituents in addressing the currently growing provision issues.T ypical reactions, which are important to catalyzei nt his respect, include CO 2 reduction, the hydrogen and oxygen evolution reactions as well as the oxygen reduction reaction. The most efficient catalysts known up-to-date for these processes usuallycontain expensive and scarce elements, substantially impeding implementation of such electrocatalysts at al arger scale. Metal-organic frameworks (MOFs)a nd their derivatives containing affordable components and building blocks, as an emerging class of porousf unctional materials, have been recently attracting ag reat attentiont hanks to their tunable structure and composition together with high surface area, just to name af ew. Up to now,s everal MOFs and MOF-derivatives have been reporteda se lectrode materials for the energy-related electrocatalytic application. In this review article, we summarize and analyze current approaches to design such materials. The design strategies to improve the Faradaic efficiency and selectivity of these catalysts are discussed. Last but not least, we discuss some novel strategies to enhance the conductivity,c hemical stability and efficiency of MOF-derived electrocatalysts.[a] Dr.he returned to TUM and took the Chair of Inorganica nd Metal-Organic Chemistry. He has been elected Vice President of the Deutsche Forschungsgemeinschaft (DFG) in 2016. His research focuses on group 13/transition metalc ompounds and clusters, precursors for chemical vapor deposition( CVD) and the materials chemistry of metal-organic frameworks (MOFs). Figure 2. a) Illustration of synthesis of the two-dimensional cobalt dithiolene catalyst for the HER. Reproduced with permission from reference [37].Copyright 2014, American Chemical Society. b) and c) The active sites of [NiFe] and [NiFeSe] hydrogenases in metalselenolate polymersand corresponding voltammetric characterisation of these materials concerning the electrochemical hydrogen evolution activity.b )a nd c) Reproduced with permission from reference [38].

Selenic Acid Etching Assisted Vacancy Engineering for Designing Highly Active Electrocatalysts toward the Oxygen Evolution Reaction

“…Considering the high price of noble metals, nonprecious metal oxides, sulfides, and selenides have attracted considerable attention as alternative OER electrocatalysts. Metal-organic frameworks (MOFs) are a category of amazing crystalline materials with ultrahigh porosity (up to 90% free volume) and enormous internal surface areas, extending beyond 6000 m 2 g -1 , [12,13] which can also be served as an excellent material platform to form transition metal derivatives with well-defined hollow morphology. [14,15] Recently, hollow-structured nanocages of transition metal selenides derived from MOFs were suggested to be promising electrocatalysts because of their large exposed surface areas,Oxygen evolution electrocatalysts are central to overall water splitting, and they should meet the requirements of low cost, high activity, high conductivity, and stable performance.…”

Evolution of metal organic frameworks as electrocatalysts for water oxidation

“…Additionally, it is worth mentioning that determination of the Tafel slope is an important tool to elucidate the mechanism involved. 13,16 Electrocatalysts for the OER OER catalysts can be classified as homogenous catalysts (molecular) and heterogeneous catalysts (with extended structure), based on the physical state of the active species. However, during the course of time, this classification appeared to be less appropriate as many homogeneous catalysts were reported not to behave as a molecular catalyst, whereas various heterogeneous catalysts were reported in which the catalytic OER was performed by a molecular functional unit present within the structure.…”

Design of Trimetallic NiMoFe Hollow Microspheres with Polyoxometalate‐Based Metal‐Organic Frameworks for Enhanced Oxygen Evolution Reaction

“…[16] The electronic structures of transition metal compounds are similar to precious metals, these characteristics endow these materials with high OER catalytic activity. [16] In recent years, based on MOFs, people have developed POMOF and MOF@MOF. [17] Polyoxometalates (POMs) contain a large number of early transition metals (Mo, W etc.…”

“…Among the various candidate materials for OER, carbon based transition metal compounds (such as oxides, [10] carbides, [11] nitrides, [12] sulfides [13] and phosphides [14] ) derived from metal‐organic frameworks (MOFs) have attracted much attention [15] . MOFs have high specific surface area and porosity, they are ideal precursors [16] . The electronic structures of transition metal compounds are similar to precious metals, these characteristics endow these materials with high OER catalytic activity [16] .…”

“…MOFs have high specific surface area and porosity, they are ideal precursors [16] . The electronic structures of transition metal compounds are similar to precious metals, these characteristics endow these materials with high OER catalytic activity [16] . In recent years, based on MOFs, people have developed POMOF and MOF@MOF [17] .…”