Metal-organic framework (MOF) nanoparticles, also called porous coordination polymers, are a major part of nanomaterials science, and their role in catalysis is becoming central. The extraordinary variability and richness of their structures afford engineering synergies between the metal nodes, functional linkers, encapsulated substrates, or nanoparticles for multiple and selective heterogeneous interactions and activations in these MOF-based nanocatalysts. Pyrolysis of MOF-nanoparticle composites forms highly porous N- or P-doped graphitized MOF-derived nanomaterials that are increasingly used as efficient catalysts especially in electro- and photocatalysis. This review first briefly summarizes this background of MOF nanoparticle catalysis and then comprehensively reviews the fast-growing literature reported during the last years. The major parts are catalysis of organic and molecular reactions, electrocatalysis, photocatalysis, and views of prospects. Major challenges of our society are addressed using these well-defined heterogeneous catalysts in the fields of synthesis, energy, and environment. In spite of the many achievements, enormous progress is still necessary to improve our understanding of the processes involved beyond the proof-of-concept, particularly for selective methane oxidation, hydrogen production, water splitting, CO2 reduction to methanol, nitrogen fixation, and water depollution.

State of the Art and Prospects in Metal-Organic Framework (MOF)-Based and MOF-Derived Nanocatalysis.

More than 95% (in volume) of all of today’s chemical products are manufactured through catalytic processes, making research into more efficient catalytic materials a thrilling and very dynamic rese...

Metal–Organic Frameworks in Heterogeneous Catalysis: Recent Progress, New Trends, and Future Perspectives

One‐dimensional (1D) nanostructured photocatalyst is a promising candidate for hydrogen (H2) generation, which can be used to deal with the energy crisis. Herein, novel 1D TiO2/CdS well‐hybridized nanofibers (NFs) were synthesized via in situ electrospinning method. These 1D hybrid NFs showed a high H2‐production rate of 2.32 mmol h−1 g−1 with an apparent quantum efficiency of 10.14 %, which was 35‐fold higher than that of pristine TiO2 NFs. X‐ray photoelectron spectroscopy (XPS) analysis and density functional theory calculation implied that the electrons transferred from CdS to TiO2 upon hybridization and created an internal electric field (IEF) pointing from CdS to TiO2. This IEF drove the photoexcited electrons in TiO2 to transfer toward CdS upon light irradiation as revealed by in situ irradiated XPS analysis, suggesting that a step‐scheme (S‐scheme) heterojunction was formed in the TiO2/CdS nanohybrids and greatly promoted the separation of electron‐hole pairs to foster efficient H2 photogeneration. The significant enhancement of photocatalytic activity was also benefited from the easy transfer for electrons in the 1D well‐distributed nanostructure of nanohybrids. This work presents a method for in situ preparing well‐distributed 1D NFs with high photocatalytic activity for H2 production via the S‐scheme pathways.

S‐Scheme Heterojunction TiO2/CdS Nanocomposite Nanofiber as H2‐Production Photocatalyst

Cobalt-mediated activation of peroxymonosulfate (PMS) has been widely investigated for the oxidation of organic pollutants. Herein, we employ cobalt-doped Black TiO_2 nanotubes (Co-Black TNT) for the efficient, stable, and reusable activator of PMS for the degradation of organic pollutants. Co-Black TNTs induce the activation of PMS by itself and stabilized oxygen vacancies that enhance the bonding with PMS and provide catalytic active sites for PMS activation. A relatively high electronic conductivity associated with the coexistence of Ti^(4+) and Ti^(3+) in Co-Black TNT enables an efficient electron transfer between PMS and the catalyst. As a result, Co-Black TNT is an effective catalyst for PMS activation, leading to the degradation of selected organic pollutants when compared to other TNTs (TNT, Co-TNT, and Black TNT) and other Co-based materials (Co_3O_4, Co-TiO_2, CoFe_2O_4, and Co_3O_4/rGO). The observed organic compound degradation kinetics are retarded in the presence of methanol and natural organic matter as sulfate radical scavengers. These results demonstrate that sulfate radical is the primary oxidant generated via PMS activation on Co-Black TNT. The strong interaction between Co and TiO_2 through Co–O–Ti bonds and rapid redox cycle of Co^(2+)/Co^(3+) in Co-Black TNT prevents cobalt leaching and enhances catalyst stability over a wide pH range and repetitive uses of the catalyst. Electrode-supported Co-Black TNT facilitates the recovery of the catalyst from the treated water.

Activation of Peroxymonosulfate by Oxygen Vacancies-Enriched Cobalt-Doped Black TiO2 Nanotubes for the Removal of Organic Pollutants

The study of hydrogen evolution reaction and oxygen evolution reaction electrocatalysts for water electrolysis is a developing field in which noble metal-based materials are commonly used. However, the associated high cost and low abundance of noble metals limit their practical application. Non-noble metal catalysts, aside from being inexpensive, highly abundant and environmental friendly, can possess high electrical conductivity, good structural tunability and comparable electrocatalytic performances to state-of-the-art noble metals, particularly in alkaline media, making them desirable candidates to reduce or replace noble metals as promising electrocatalysts for water electrolysis. This article will review and provide an overview of the fundamental knowledge related to water electrolysis with a focus on the development and progress of non-noble metal-based electrocatalysts in alkaline, polymer exchange membrane and solid oxide electrolysis. A critical analysis of the various catalysts currently available is also provided with discussions on current challenges and future perspectives. In addition, to facilitate future research and development, several possible research directions to overcome these challenges are provided in this article.

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Recent Progresses in Electrocatalysts for Water Electrolysis

Facile synthesis of NiS anchored carbon nanofibers for high-performance supercapacitors

Co@Co3O4 nanoparticle embedded nitrogen-doped carbon architectures as efficient bicatalysts for oxygen reduction and evolution reactions

N-doped porous carbon-encapsulated Fe nanoparticles as efficient electrocatalysts for oxygen reduction reaction

Hollow and core–shell particles are currently attracting global attention because of their special properties We herein proposed a facile self-sacrificial template strategy for the synthesis of cobalt tetraoxide (Co3O4) with hollow and core–shell nanostructures Starting with metal formate framework (MFF) template [CH3NH3][Co(HCOO)3], a series of core–shell nanostructure MFF@Co(OH)2 microboxes and hollow Co(OH)2-H were successfully obtained through a reaction between the MFF template and sodium hydroxide (NaOH) combined with different washing processes Finally, hollow and core–shell nanostructure Co3O4 products were obtained after calcination, which inherited the structures from corresponding precursors In addition, the formation processes of hollow and core–shell nanostructures were studied Moreover, the catalytic activity of the as-obtained Co3O4 for carbon monoxide (CO) oxidation was investigated Such hollow and core–shell nanostructures gave different physiochemical properties Hollow structure C

Chunling Qi

Papers

Facile synthesis of NiS anchored carbon nanofibers for high-performance supercapacitors

Co@Co3O4 nanoparticle embedded nitrogen-doped carbon architectures as efficient bicatalysts for oxygen reduction and evolution reactions

N-doped porous carbon-encapsulated Fe nanoparticles as efficient electrocatalysts for oxygen reduction reaction

Hollow and Core–Shell Nanostructure Co3O4 Derived from a Metal Formate Framework toward High Catalytic Activity of CO Oxidation