Themed collection Nanoscale Horizons, Nanoscale, and ChemComm: Nanocatalysis

This state-of-the-art review of MXene-based catalysts in CO₂ electro/photoreduction places an emphasis on synthesis approaches, surface termination modulation, heterostructure engineering and reaction mechanisms.

We focus on the new horizons in operando/in situ characterisation techniques in electrocatalysis, providing a critical analysis of how advanced in situ techniques help us to deepen our understanding of reaction mechanisms and material evolution.

The conversion of CO_x into value-added green aromatics is considered as a promising route to achieve the world's decarbonization due to its considerable thermodynamic driving force and atomic economy where low H/C ratio aromatics are chosen as a product.

This article reviews the strategies of maximizing CO₂ photoreduction rates in distinguished ZnS-based photocatalytic systems by continuously optimizing the reaction medium and photocatalysts.

The synthesis, characterization, and applications of rare earth-based single-atom catalysts.

The review examines the areas: (i) routes for synthesis of transition metal-based LDHs, (ii) recent developments in transition metal-based LDHs for photo(electro)chemical water splitting, (iii) a summary of the structure–property relationships therein.

Cooperativity in single atom catalysis greatly exceeds the (important) metal–support interaction, and other types of synergies (with a nanoparticle – NP, a second SA – SA₂, or a ligand/heteroatom – X) are described in this mini-review.

Epitaxial oxide thin films enable electrocatalyst design, e.g. for the oxygen evolution reaction, based on atomic-level structure–property–functionality relationships.

This review summarizes the preparation methods of MXene and the applications of MXene in electrocatalytic hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, carbon dioxide reduction reaction and nitrogen reduction reaction.

In this feature article, we discuss the significant role of the pre-oxidation reaction during urea electro-oxidation, and summarize the detailed strategies and recent advances in promoting the pre-oxidation reaction.

Recent efforts on the use of controlled metal nanoparticles to establish structure–performance relationships in plasmonic catalysis are discussed.

Recent advances in heteroatom-doped carbon electrocatalysts showing tailored 4e⁻ and 2e⁻ selectivity for oxygen reduction reaction are reviewed.

Low-dimensional copper oxide nanostructures are a promising family of functional nanomaterials. This article reviews recent progress in fabrication technologies for CuO nanostructures and gives examples of their leading-edge applications.

Isolated metal atoms on supports tend to migrate and agglomerate in the processes of catalyst design and construction, thus achieving precise control of high metal loading and single-atomic dispersion is significant.

Current popular transition metal-based electrocatalysts developed for HER/OER in water splitting at high current density are critically reviewed and discussed.

This review describes state-of-art techniques and knowledge on the creation of high-performance heterogeneous catalysts using atomically precise metal nanoclusters.

2D MOF-based materials with unique characteristics have great potential in various electrocatalytic, photocatalytic and thermocatalytic applications.

In this review we highlight the recent progress in 2DM growth on LMCat, which in combination with in situ characterization presents a viable and large-scale sustainable direction that has the prospect of achieving defect-free 2D materials.

A new catalytic approach is pioneered to achieve CO₂ methanation via a single atom alloy Ir/Ni catalyst using a ball-milling method.

Au/CeO₂ fabricated by loading tannic acid-reduced Au on various structurally engineered CeO₂ are applied to catalytic nitrobenzene transfer hydrogenation with isopropanol as a green H₂ provider, revealing a detailed structure–activity relationship.

Heterostructures of metal halide perovskites and TiO_x are efficient photocatalytic materials owing to the combination of the high absorption coefficients and long charge-carrier lifetimes of perovskites, and efficient photocatalytic activity of TiO_x.

The stochastic motion (45 kHz) of a biped in a dynamic slider-on-deck kicks out a basic organocatalyst into solution while parallel freeing a silver(I) site with both synergistically running a tandem Michael addition/hydroalkoxylation cyclization.

5 nm SnFe₂O₄ nanoparticle, an un-explored inverse spinel ferrite material, has been explored as electrode material for overall water splitting study where Fe sites are OER active and Sn sites promote electron conduction and HER active.

We report a smart ion-exchange strategy to anchor molybdenum oxide particles on charge-modulated conjugated triazine frameworks (Mo/CTF-I) for electrochemically fixing nitrogen.

A heterogeneous catalyst consisting of bimetallic rhodium-ruthenium particles immobilized on carbon nanotubes was used in the hydroboration reaction and proved highly effective for a variety of alkenes and alkynes.

V₂O₅ nanoclusters can inhibit CoS₂ from serious surface oxidation in air, and the lower surface oxidation degree, the better HER performance.

Layer structured MoS₂ with intercalation of polyaniline and crystal defects was prepared, which delivers high reversible capacity and excellent cycle stability, including 77.8 mA h g⁻¹ at 1 A g⁻¹ and near 100% retention rate after 750 cycles.

Four TM₁TM₂@C₉N₄ candidates (TM₁TM₂ = NiRu, FeNi, TiNi, and NiZr) with end-on N₂ adsorption configuration, and two candidates (TM₁TM₂ = TiNi and TiFe) with side-on adsorption configuration, were screened out as high efficiency NRR catalysts.

A cation exchange strategy is proposed to convert layered Ti₃C₂–Na–TiO₂ MXene nanofibers into Ti₃C₂–Co–TiO₂ MXene nanoparticle arrays with numerous heterogeneous interfaces, which deliver excellent oxygen evolution reaction (OER) activity.

In this work, a Bi-doped Co₃O₄ nanosheet array grown on Ni foam was used as an efficient bifunctional catalyst, which shows high activity and good stability toward HMF oxidation and hydrogen evolution.

The Cu and Si co-doping could rationally regulate the electronic structure of TiO₂ nanosheets and maneuver the reactive oxygen species for methane activation, which achieves significant photocatalytic methane conversion into ethane.

A perovskite-derived nickel phosphide catalyst exhibits excellent electrocatalytic oxidation performance for biomass valorization to replace the competitive oxygen evolution reaction.

As an electrocatalyst for nitrate reduction, CoO nanoparticle decorated N-doped carbon nanotubes show a large NH₃ yield up to 9166.37 μg h⁻¹ cm⁻² and a high faradaic efficiency of 93.63% in 0.1 M NaOH with 0.1 M NO₃⁻.

We report the proof-of-concept design of interfacial sites with a selectivity-governing and hydrogen evolution reaction-suppressing domain (Bi) and an electrokinetic-promoting domain (Cu₂S) for efficient CO₂ electroreduction to formate.

A bimetallic FeCo₂O₄ spinel nanowire array grown on carbon cloth is highly active and stable for electrocatalytic NO₃⁻ reduction to NH₃, capable of attaining a large NH₃ yield of 4988 μg h⁻¹ cm⁻² with a high faradaic efficiency of 95.9%.

Cobalt nanoparticle-decorated pomelo-peel-derived carbon acts as a highly active electrocatalyst for NO₃⁻–to–NH₃ conversion, capable of attaining a large faradaic efficiency of 90.1% and an ultrahigh NH₃ yield of 1.1 mmol h⁻¹ mg_cat.⁻¹.

In situ grown TiO₂ nanobelt array with oxygen vacancies on Ti plate acts as a high-efficiency and stable catalyst for electrochemical NO₂⁻ reduction to NH₃, attaining a large NH₃ yield of 7898 μg h⁻¹ cm⁻² with a high faradaic efficiency of 92.7%.

Pd-doped TiO₂ nanoparticles as an effective NRR electrocatalyst present a large NH₃ yield of 17.4 μg h⁻¹ mg_cat.⁻¹ and a high faradaic efficiency of 12.7% at −0.50 V vs. RHE in 0.1 M Na₂SO₄ electrolyte.

For the first time, a pore-scale model is developed to simulate the reactive transport of oxygen, protons, and electrons in the catalyst layer of PEM fuel cells.

CF@Cu₂O is a superb NO₂⁻ reduction reaction electrocatalyst, achieving high-efficiency electrosynthesis of ammonia from nitrite with an excellent ammonia yield of 7510.73 μg h⁻¹ cm⁻² and Faraday efficiency of 94.21%.

A NiO nanosheet array is active for NH₃ electrosynthesis via a NO reduction reaction, attaining a faradaic efficiency of 90% and an NH₃ yield of 2130 μg h⁻¹ cm⁻². Its aqueous Zn–NO battery offers a power density of 0.88 mW cm⁻² and an NH₃ yield of 228 μg h⁻¹ cm⁻².

As an electrocatalyst for N₂-to-NH₃ conversion, an amorphous WC thin film shows a large NH₃ yield of 43.37 μg h⁻¹ mg⁻¹_cat. with a high faradaic efficiency of 21.65% at −0.10 V vs. RHE in 0.5 M LiClO₄.

A mesoporous binary CoS/MoS₂ with active hetero-interfaces was assembled through a facile sulphuration process from a CoMo-bimetallic HZIF, which exhibited excellent electrocatalytic OER and HER activity, and superior water splitting performance.

Type II heterostructures consisting of red/yellow g-C₃N₄ nanosheets prepared via edge-epitaxial growth revealed superior photocatalytic activities for enhanced H₂ generation and CO₂ reduction.

Annealing core@shell nanoparticles (NPs) yields high-entropy alloy NPs. Owing to their dispersed Pt/Pd content and low elemental diffusivity, they exhibit enhanced electrocatalytic performance and durability for the oxygen reduction reaction.

An alternating-reduction approach is developed to fabricate PtPd hollow nanocubes with highly catalytically-favoured {100} facets and enhanced alloy effect for efficient methanol oxidation reaction.

Selenium spheres decorated with Pt nanoparticles were found to be efficient for alcohol fuel oxidation in fuel cells.

Plasmonic Mg cores capture light to decrease the activation energy and increase the rate of acetylene hydrogenation on Pd nanoparticles.

Colloidal Ag particles decorated with Fe₃O₄ islands can be electrochemically or photochemically activated as inverse catalysts for C(sp²)–H heteroarylation.

Hollow mesoporous Co–N–C@mSiO₂ catalysts derived from ZIF-67 via the encapsulation–pyrolysis strategy exhibit excellent performance and good stability for furfural hydrogenation.

2D MoS₂/BiOBr van der Waals heterojunctions produced through liquid phase exfoliation are tested as catalysts for photoelectrochemical hydrogen evolution, with the 1% w/w composition exhibiting good performance and stability to photocorrosion.

A three-dimensional cobalt sulfide/Co, N and S multi-heteroatom codoped carbon was synthesized as a trifunctional electrocatalyst through one-step sulfidation of zeolitic-imidazolate frameworks, showing outstanding ORR, OER and HER performance.

We have designed an extended porous organic polymer with a covalent alliance of distinct Ru sites and investigated its electrocatalytic water oxidation performance.

Single Ni atom anchored on pristine and N-doped VS₂ monolayer can perform as bifunctional catalyst for ORR and OER.

A novel strategy to synthesize silver and gold nanoparticles–enzyme hybrids based on using enzyme-polymer bioconjugates has been developed. These nanobiohybrids were successfully used as dual activity catalysts in the stereoselective hydrolysis/cyclization cascade reaction.

Defect-rich bimetallic Co–Mo sulfide/carbon composites derived from polyoxometalate encapsulated polydopamine-decorated ZIF nanocubes exhibit a remarkable improvement in electrocatalyic performance towards both hydrogen and oxygen evolution.

Well-regulated OOH* stabilization is revealed to be the origin of bifunctional ORR/OER activity.

Product selectivity in catalytic semi hydrogenation of alkynes could be controlled by offering a steric hindrance effect through organogel-assisted porous-organic-polymer (POP) supported Cu catalysts (Cu@TpRb-POP).

Sodium naphthalenide exfoliated 3R polytype of MoS₂ outperforms the 2H polytype due to much higher conversion to the metallic 1T phase.

Self-supported Ni-doped Mo₂C nanoflowers assembled with ultrathin nanosheets on CFP as an excellent electrocatalyst for the hydrogen evolution reaction were prepared via a molten salt method.

Preparation of hybrid catalyst by the coordination of polyvinylpyrrolidone (PVP) and monodisperse zeolitic imidazolate framework (ZIF-8), entangled by carbon nanotubes (CNTs) through the pyrolysis process.

3D porous Ni/NiO_x was synthesized via the freeze-drying method. Freeze drying method could improve the surface area and catalytic activation of Nickel hydroxide nanosheet.

Colloidal Cu and Ag nanoparticles retain their shape during the CO₂ reduction reaction (−0.8 V vs. RHE) due to immiscibility of the lattices and synergy at the nanoscale results in enhanced methane and C₂ product formation.

High electrical conductivity and tendency in triggering the UOR via a direct electro-oxidation mechanism result in superior UOR activity for Ni₂P nanoflakes.