A Surfactant‐Free and Scalable General Strategy for Synthesizing Ultrathin Two‐Dimensional Metal–Organic Framework Nanosheets for the Oxygen Evolution Reaction

Abstract

Metal–organic framework (MOFs) two‐dimensional (2D) nanosheets have many coordinatively unsaturated metal sites that act as active centres for catalysis. To date, limited numbers of 2D MOFs nanosheets can be obtained through top‐down or bottom‐up synthesis strategies. Herein, we report a 2D oxide sacrifice approach (2dOSA) to facilely synthesize ultrathin MOF‐74 and BTC MOF nanosheets with a flexible combination of metal sites, which cannot be obtained through the delamination of their bulk counterparts (top‐down) or the conventional solvothermal method (bottom‐up). The ultrathin iron–cobalt MOF‐74 nanosheets prepared are only 2.6 nm thick. The sample enriched with surface coordinatively unsaturated metal sites, exhibits a significantly higher oxygen evolution reaction reactivity than bulk FeCo MOF‐74 particles and the state‐of‐the‐art MOF catalyst. It is believed that this 2dOSA could provide a new and simple way to synthesize various ultrathin MOF nanosheets for wide applications.

CO2 controls the oriented growth of metal-organic framework with highly accessible active sites

“…First, the N-Cu(BDC) synthesized by CO 2 has nanometer sizes in all the three dimensions, which is favorable to increasing the density of catalytic active sites. Second, the N-Cu(BDC) synthesized by CO 2 has abundant unsaturated coordination Cu sites on surfaces that are available for catalysis [40][41][42] , which are superior to the dormant and fully coordinated framework metal ions of MOFs that are unavailable for catalysis. Owing to these unique features, the as-synthesized N-Cu(BDC) exhibits greatly enhanced activity for catalyzing the oxidation reactions of alcohols as compared with B-Cu(BDC).…”

Strong Electronic Interaction Enhanced Electrocatalysis of Metal Sulfide Clusters Embedded Metal–Organic Framework Ultrathin Nanosheets toward Highly Efficient Overall Water Splitting

“…In this regard, MOFs in the form of 2D ultrathin nanosheets are highly desirable and have been successfully developed by ultrasonication-assisted exfoliation, liquidliquid interfacial growth, organic ligand confined synthesis, sublimation-vapor phase transformation, epitaxial growth, sacrificial template growth, and exhibited impressive electrocatalytic performances. [26][27][28][29][30][31] Introducing heterogeneous species into the pristine MOFs is another brilliant way to boost the electrocatalytic activity of MOFs. The conductivity and electrocatalytic performance of MOFs are enhanced by post-synthesis plasma treatment to generate tiny CuS or CoO x nanoparticles in MOFs.…”

Facile electron delivery from graphene template to ultrathin metal-organic layers for boosting CO2 photoreduction

“…Nanosizing MOFs into ultrathin metal-organic layers (MOLs) can e ciently accelerate mass transport / electron transfer and create abundant readily accessible active sites to ensure high activity in various catalytic reactions. [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] Moreover, ultrathin MOFs with limited number of atoms represent ideal models to explore structure-performance relationships for further rationally constructing e cient catalysts at atomic/molecular levels. For example, a mono-carboxylic bipyridine ligand was utilized to assemble Re-/Mn-Ru molecules into monolayer Hf-based MOLs, 20 the resulting Re-Ru-based MOLs can sustainably reduce CO 2 to CO under real sunlight for one week.…”