Copper nanoparticle-embellished Zr-based metal-organic framework for electrocatalytic hydrogen evolution reaction

Rational design and synthesis of atomically precise nanocluster-based nanocomposites: a step towards environmental catalysis

Atomically precise metal nanoclusters (NCs) and metal-organic frameworks (MOFs) possess distinct properties that can present challenges in certain applications. However, integrating these materials to create new composite functional materials has gained significant interest due to their unique characteristics through a range of applications, particularly in catalysis. Considering MOFs as hosts and NCs as guests, several synergistic effects have been observed in composites, particularly in environmental catalytic reactions. However, the precise role of encapsulated NCs within the MOF pore structure is still in its infancy. Besides, stabilizing NCs, whether through intact ligands or without ligands via the MOF host, presents challenges that are currently being investigated. This feature article reviews recent advancements in the synthesis of NC@MOF composites, focusing on cutting-edge strategies for selecting MOFs and the roles of NC ligands, as well as characterization and catalytic applications.

Zirconium-based metal-organic frameworks and their roles in electrocatalysis

Due to their exceptional chemical stability in water and high structural tunability, zirconium(IV)-based MOFs (Zr-MOFs) have been considered attractive materials in the broad fields of electrocatalysis. Numerous studies published since 2015 have attempted to utilise Zr-MOFs in electrocatalysis, with the porous framework serving as either the active electrocatalyst or the scaffold or surface coating to further enhance the performance of the actual electrocatalyst. Herein, the roles of Zr-MOFs in electrocatalytic processes are discussed, and some selected examples reporting the applications of Zr-MOFs in various electrocatalytic reactions, including several studies from our group, are overviewed. Challenges, limitations and opportunities in using Zr-MOFs in electrocatalysis in future studies are discussed.

Three-Dimensional Network of Highly Uniform Cobalt Oxide Microspheres/MXene Composite as a High-Performance Electrocatalyst in Hydrogen Evolution Reaction

Due to its affordable cost, excellent redox capability, and relatively effective resistance to corrosion in alkaline environments, spinel Co3O4 demonstrates potential as a viable alternative to noble-metal-based electrocatalysts. Nevertheless, these materials continue to exhibit drawbacks, such as limited active surface area and inadequate intrinsic conductivity. Researchers have been trying to increase the electrical conductivity of Co3O4 nanostructures by integrating them with various conductive substrates due to the low conductivity of pristine Co3O4. In this study, uniform cobalt glycerate solid spheres are first synthesized as the precursor and subsequently transformed into cobalt oxide microspheres by a simple annealing procedure. Co3O4 grown on the surface of Ti3C2Tx-MXene nanosheets (Co3O4/MXene) was successfully synthesized through electrostatic attraction. In order to create a positively charged surface, the Co3O4 microspheres were treated with aminopropyltriethoxysilane. The Co3O4/MXene exhibited a low overpotential of 118 mV at 10 mA cm-2 and a Tafel slope of 113 mV dec-1 for the hydrogen evolution reaction, which is much lower than the pristine Co3O4 at 232 and 195.3 mV dec-1.