Different from isolated metal atoms and large metal nanoparticles (NPs), supported metal clusters (SMCs) possess distinct geometric and electronic structures and thus exhibit enhanced activity and designated selectivity in catalysis. So far, with the development in synthetic methodologies and characterization techniques, SMCs with fine structures could be constructed and well-defined at the atomic level. In addition, based on computational modeling of SMCs, theoretical calculations corroborated well with experimental results, providing in-depth insights into the structure–property relationship for SMCs in catalysis. In this Review, classic synthetic strategies and key characterization techniques of SMCs are summarized. Subsequently, the applications of SMCs in important catalytic reactions based on recent studies are discussed, including aerobic oxidation, hydrogenation, dehydrogenation, water–gas shift (WGS) reaction, and photocatalytic reactions. In particular, the importance of the cluster size-effect and metal–support interactions in determining the catalytic performance of SMCs is highlighted. Lastly, challenges and prospects in SMCs’ catalysis are illustrated.

Synthesis of methanol from CO 2 hydrogenation is a highly attractive route for recycling greenhouse gases to produce clean and value-added fuels and chemicals, simultaneously mitigating the CO 2 emission and obtaining useful feedstock. Heterogeneous catalysts have been the pillar for CO 2 catalytic transformation. The strong metal−support interaction (SMSI) is of great importance for supported catalysts. In addition, the SMSI can be used to enhance the catalytic activity and selectivity to the desired product as well as the stability of the catalysts. Understanding the SMSI is the key to gain deep insights into the structure−activity relationship, which provides valuable guideline for rational design of highly efficient and selective catalysts for methanol synthesis from CO 2 hydrogenation. In this review, we present an overview of the advances of CO 2 reduction to methanol with focus on catalytic performance, structure characterization, and reaction mechanism for rational design of desired catalysts.

Herein we report an efficient and recyclable catalytic system for tandem CO2 capture and N‐formylation to value‐added chemicals. CO2 is apt to be captured by morpholine solution, while a highly efficient heterogeneous catalyst, isolated iridium atoms supported over nanadiamond/graphene, is discovered to be highly reactive for the formylation of morpholine, leading to the formation of N‐formylmorpholine with excellent productivity (with a turnover number of 5 120 000 in a single batch reaction) and selectivity (>99 %). In addition, the CO2 captured by morpholine under atmospheric conditions can be converted to N‐formylmorpholine with decent conversion (51 %), which realizes the integration of CO2 capture and conversion to value‐added chemicals.

Atomically dispersed Pd (Pd 1 ) catalysts supported on annealed nanodiamond were prepared through a deposition−precipitation method toward propane direct dehydrogenation (PDDH). The Pd 1 catalyst is superior to Pd cluster/particle catalysts in activity and stability. Combining experimental characterizations and DFT calculations revealed that atomically dispersed Pd species have strong interactions with the hybrid nanodiamond/graphene support, leading to better resistance to coke formation. More importantly, Pd sintering is inevitable in the cluster/particle catalysts, while the high dispersion of Pd species in Pd 1 catalyst is well-preserved during the reaction, which is caused in part by the redistribution or migration of Pd single atoms onto the carbonaceous compound (coke). As a result, the Pd 1 catalyst shows significantly better activity and stability in high-reaction temperatures than Pd cluster/particle catalysts. This work reveals deeper insights on designing highly dispersed metal catalysts with the ability of in situ regeneration of active sites in high-temperature catalytic reactions.

The amino naphthalene 2-cyanoacrylate (ANCA) probe is a kind of fluorescent amyloid binding probe that can report different fluorescence emissions when bound to various amyloid deposits in tissue, while their interactions with amyloid fibrils remain unclear due to the insoluble nature of amyloid fibrils. Here, all-atom molecular dynamics simulations were used to investigate the interaction between ANCA probes with three different amyloid fibrils. Two common binding modes of ANCA probes on Aβ40 amyloid fibrils were identified by cluster analysis of multiple simulations. The van der Waals and electrostatic interactions were found to be major driving forces for the binding. Atomic contacts analysis and binding free energy decomposition results suggested that the hydrophobic part of ANCA mainly interacts with aromatic side chains on the fibril surface and the hydrophilic part mainly interacts with positive charged residues in the β-sheet region. By comparing the binding modes with different fibrils, we can find that ANCA adopts different conformations while interacting with residues of different hydrophobicity, aromaticity, and electrochemical properties in the β-sheet region, which accounts for its selective mechanism toward different amyloid fibrils.

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A metal-free radical oxidative carbonylation of alkanes is demonstrated, yielding esters and imides by means of di-tert-butylperoxide as an oxidant. Various alkanes, alcohols and amides were compatible in this system generating the desired carbonyl products in up to 86% yields. We proposed a plausible radical cross-coupling process based on the preliminary mechanistic studies.

Tremendous research efforts have been devotedto new methods of water decontamination and water splitting at low cost and less energy consumption. Herein, we developed a robust electrochemical strategy with an efficient membrane electrode to remove refractory organic pollutants and simultaneously produce pure hydrogen in wastewater. Firstly, the membrane anode was constructed with a three-dimensional (3D) nanoneedle array of Co 3 O 4 and Ti membrane, exhibiting superior degradation of phenol and dye with Na 2 SO 4 as the electrolyte in a conventional electrocatalytic membrane reactor (ECMR). For the phenol degradation, ≥99% removal efficiency of phenol, 99.5% chemical oxygen demand (COD) removal rate, 92.5% total organic carbon (TOC) removal rate, 88.7% current efficiency and 0.061 kW h (g COD) −1 energy consumption can be obtained. For the dye degradation, ≥99% decolor efficiency and 95.2% COD removal rate, 87.6% TOC removal rate, 82.1% current efficiency and 0.12 kW h (g COD) −1 energy consumption can be achieved. The obtained membrane electrode can provide more active CoOOH sites, dramatically increase the electric fields and overcome mass transfer limitation in a flowthrough configuration, thereby significantly enhance the catalytic performance. Finally, we designed a H-type ECMR with the proton exchange membrane (PEM) as the separator for pure H 2 production, i.e., PEM-ECMR, demonstrating superior degradation performance of phenol and dye, stable production of high-purity hydrogen (11-15 mL h −1 ), and excellent long-term stability (100 days) and low voltage input (below 3.0 V). This work demonstrates a promising pathway towards reducing cost and energy consumption for water decontamination and simultaneous hydrogen production.