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A scalable, and cost-effective method was employed to prepare self-supported CuSn bimetallic catalyst on carbon paper. The obtained CuSn catalyst demonstrates high faradaic efficiency of CO around or above 90% at a broad potential range from −0.7 to −1.8 V vs. reversible hydrogen electrode, greatly surpassing Cu or Sn counterparts. [ABSTRACT FROM AUTHOR]

The use of quasi-enantiomeric substrates and ESI-MS as an analytical tool has made it possible to determine the intrinsic enantioselectivity of chiral catalysts by monitoring catalytic intermediates. In this way, potential problems of methods based on product analysis, which may be caused by catalytically active impurities, partial dissociation of a chiral ligand–metal complex, or a non-catalytic background reaction can be avoided. ESI-MS-based screening is fast, reliable, and operationally simple, as it does not require work-up or purification steps. Moreover, mixtures of catalysts with different molecular masses can be screened simultaneously, which is not possible with methods relying on product analysis. In this way catalyst libraries prepared in one batch by combinatorial methods can be screened without the need to synthesize and purify the catalysts individually. This screening method was successfully applied to Pd-catalyzed allylic substitutions and metal-catalyzed and organocatalytic Diels–Alder reactions. [ABSTRACT FROM AUTHOR]

Chiral bifunctional phase transfer catalysts introducing bis(diarylhydroxymethyl) substituents at 3,3′-positions of the chiral binaphthyl core were successfully applied to asymmetric fluorination of cyclic β-keto esters with high enantioselectivities. [ABSTRACT FROM AUTHOR]

A homodinuclear Ni2-Schiff base 1complex (0.1–1 mol%) promoted the direct catalytic asymmetric aldol reaction of β-keto esters with formaldehyde, giving hydroxymethylated adducts in 94–66% ee. [ABSTRACT FROM AUTHOR]

α′-Hydroxyenones undergo clean, catalytic amidations with amines promoted by the combination of an N-heterocyclic carbene and 1,2,4-triazole. [ABSTRACT FROM AUTHOR]

This work describes a highly active and stable acid activated carbon fibre and amorphous MoSx composite hydrogen evolution catalyst. The increased electrochemical-surface area is demonstrated to cause increased catalyst electrodeposition and activity. These composite electrodes also show an improved stability towards the mechanical degradation of the MoSx catalyst. [ABSTRACT FROM AUTHOR]

We report for the first time, the performance of black pearl (BP) carbon as an electrocatalyst in all-vanadium redox-flow-batteries. Our results show significant suppression in peak potential separation (faster in kinetics than CNTs), 17% improvement in energy efficiency (when compared with CNTs) and good activity retention after 800 potential cycles. [ABSTRACT FROM AUTHOR]

The rational design of high-efficiency electrocatalysts for application in water oxidation in alkaline media remains a great challenge. In this paper, Ni3+-rich nanograss-like Mo-doped Ni3S2/NiS/VS arrays grown on nickel foam (denoted as Mo-NiVS@NF) have been successfully constructed through a hydro/solvothermal method. Interestingly, Mo-NiVS@NF exhibits superior catalytic OER performance, needing an overpotential of 217 mV to drive a current density of 10 mA cm−2, outperforming most previously reported NiS-based electrocatalysts. The result indicates that the Ni3+-rich active sites caused by the modulation of the electronic structure environment via the introduction of V and high-valency Mo play an important role in the high activity for the OER. Moreover, this catalyst shows high long-term electrochemical durability. [ABSTRACT FROM AUTHOR]

Owing to the advantage of atomic utilization, the single-atom catalyst has attracted much attention and been employed in multifarious catalytic reactions. Its definite site configuration is favorable for exploring the actual active centers and corresponding reaction mechanism. At the atomic scale, the tunable site configuration, from central metal atoms, coordinated heteroatoms, peripheral dopants, and feasible polymetallic centers to the synergetic intrinsic carbon defects, can effectively augment the intrinsic activity for oxygen reduction reaction (ORR). From a practical viewpoint, the propagation strategies of single-atom sites, the loading-activity relation and the structural retention during practical tests are crucial for the industrial applications. Furthermore, the activity contribution of multiple additional active centers including the active carbon sites and the pony-size well-wrapped metal species should be acknowledged. From the perspective mentioned above, this paper thoroughly analyses the consensuses, controversies, challenges and possible solutions based on the current research progress, thereby providing inspiration and guidance for the active center engineering of single-atom catalysts. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting, which is driven by renewable energy input to produce oxygen, has been widely regarded as a promising strategy in the future energy portfolio. The two-dimensional structure based on CoOOH nanosheets is easy to handle in the preparation process, low in cost, and has a small overpotential during water decomposition. Therefore, CoOOH two-dimensional materials have been widely used as electrocatalysts for the oxygen evolution reaction (OER). In this paper, we summarize the application of two-dimensional CoOOH nanosheets in the field of oxygen production from electrocatalytic water splitting. First, the different preparation methods of two-dimensional CoOOH nanosheets are briefly introduced. The structure–activity relationship of the two-dimensional CoOOH catalyst was analyzed from different viewpoints, such as doping, defects, etc. Finally, different catalytic mechanisms of CoOOH-based catalysts are discussed, and studies at the density functional theory (DFT) level are also provided to support the above mechanisms. To improve the readability of this review, a concise overview at the end of each section is given to illustrate some of the characteristics and trends of the studies in the corresponding part. The opportunities and challenges of two-dimensional CoOOH as an electrocatalyst in the future are summarized in the Conclusion section. This work will provide new insights and perspectives to the readers to understand the role of CoOOH nanosheets in the OER process. [ABSTRACT FROM AUTHOR]

This paper demonstrates the potential of Eu2O3 and Gd2O3 as catalysts for non-oxidative propane dehydrogenation to propene. They reveal a higher activity than the state-of-the-art bare ZrO2-based catalysts due to the higher intrinsic activity of Gdcus or Eucus in comparison with that of Zrcus (cus = coordinatively unsaturated). [ABSTRACT FROM AUTHOR]

This paper reports on a binuclear Co(II)Pc which exhibits a previously unknown extremely high catalytic activity for the oxidation of a thiol to the corresponding disulfide. The high activity is explained by an electronic contact between the two Co centres in the complex. [ABSTRACT FROM AUTHOR]

The electrocatalytic nitrogen reduction reaction (NRR) is a highly promising process for synthesizing ammonia and holds great potential to replace the traditional Haber–Bosch process. Here, we report a novel flower-shaped ZnS/CoS composite electrocatalyst for the NRR. Remarkably, the ZnS/CoS-105 heterojunction catalyst achieved an NH3 yield rate of 20.42 μg h−1 mgcat.−1 and a faradaic efficiency (FE) of 11.83% at −0.45 V VS. RHE in an aqueous 0.1 M Na2SO4 solution. In addition, ZnS/CoS-105 showed remarkable stability (up to 24 h) for the NRR process. [ABSTRACT FROM AUTHOR]

This paper reports a possible mechanism of acetic acid formation from CO2, CH3I and H2 in aqueous media and the central role played by a water-soluble Rh-based electron storage catalyst. In addition to water-solubility, we also report the crystal structures of two presumed intermediates. These findings together reveal (1) the advantage of water, not only as a green solvent, but also as a reactive Lewis base to extract H+ from H2, (2) the role of the metal (Rh) centre as a point for storing electrons from H2 and (3) the importance of an electron-withdrawing ligand (quaterpyridine, qpy) that supports electron storage. [ABSTRACT FROM AUTHOR]

An effective and safe route is proposed to prepare supported Mo2C-based catalysts from organic–inorganic hybrids, which exhibit high activity and stability for producing H2from methanol catalytic decomposition. [ABSTRACT FROM AUTHOR]

Herein we describe the stoichiometric and catalytic carbene-transfer reactivity of iron(II) alkoxide complexes with iodonium ylide precursors. Treatment of PhIC(CO2Me)2 with styrene in the presence of catalytic amounts of several different Fe(OR)2(THF)2 precursors results in efficient cyclopropanation for a variety of styrenes. Computational and reactivity studies suggest a novel remote metallocarbene/vinyl radical intermediate, Fe(OR)2(κ2-(OC(OMe))2C), which could be responsible for the reactive nature of the catalyst. [ABSTRACT FROM AUTHOR]

A water oxidation catalyst Ru-bcs (bcs = 2,2′-bipyridine-6′-carboxylate-6-sulfonate) with a hybrid ligand was reported. Ru-bcs utilizes the electron-donating properties of carboxylate ligands and the on-demand coordination feature of sulfonate ligands to enable a low onset potential of 1.21 V vs. NHE and a high TOF over 1000 s−1 at pH 7. The adaptive chemistry uncovered in this work provides new perspectives for developing molecular catalysts with high efficiency under low driving forces. [ABSTRACT FROM AUTHOR]

Here, we describe an iron-catalyzed benzylic C-H thiolation of alkylarenes via photoinduced ligand-to-metal charge-transfer. The protocol features operational simplicity, mild reaction conditions, and the use of FeCl3 as catalyst and thiols/disulfides as sulfur sources, which enables the transformation of diverse benzylic C-H bonds into C-S bonds with a high efficiency. [ABSTRACT FROM AUTHOR]

Unprecedented ring-opening polymerization of quinazolinones to produce novel polyacylamidines, led by a unique cooperation between a cesium metal center and imino-phosphanamidinate ligand, was developed. Morphological studies revealed the formation of a unique macromolecular assembly producing nanofibers in the absence of a templating agent with excellent control of molecular weights and polydispersity index. [ABSTRACT FROM AUTHOR]

The electrosynthesis of hydrogen peroxide (H2O2) via a selective two-electron oxygen reduction reaction (2e− ORR) presents a green and low-energy-consumption alternative to the traditional, energy-intensive anthraquinone process. This review encapsulates the principles of designing relational electrocatalysts for 2e− ORR and explores remaining setups for large-scale H2O2 production. Initially, the review delineates the fundamental reaction mechanisms of H2O2 production via 2e− ORR and assesses performance. Subsequently, it methodically explores the pivotal influence of microstructures, heteroatom doping, and metal hybridization along with setup configurations in achieving a high-performance catalyst and efficient reactor for H2O2 production. Thereafter, the review introduces a forward-looking methodology that leverages the synergistic integration of catalysts and reactors, aiming to harmonize the complementary characteristics of both components. Finally, it outlines the extant challenges and the promising avenues for the efficient electrochemical production of H2O2, setting the stage for future research endeavors. [ABSTRACT FROM AUTHOR]

Drawing on independent work carried out by academic and industrial researchers using the immobilized TEMPO catalyst SiliaCat TEMPO, in this study we show how shifting the carboxylation process mediated by TEMPO in solution to a process mediated by the above-mentioned hybrid sol–gel catalyst allows the synthesis of insoluble polysaccharide nanofibers of superior quality, eliminating waste. This will dramatically reduce the polysaccharide nanofiber production costs opening the route to large-scale production and uptake of these versatile nanofibers in a variety of functional products where their use has been limited by high cost. The results of this study will be useful for catalysis and biotechnology researchers as well as for chemistry educators teaching green chemistry, nanochemistry, and catalysis using the outcomes of recent research. [ABSTRACT FROM AUTHOR]

ZnO quantum dots (QDs) supported on porous nitrogen-doped carbon (ZnOQDs/P-NC) exhibited excellent electrochemical performance for the electroreduction of CO2 to CO with a faradaic efficiency of 95.3% and a current density of 21.6 mA cm−2 at −2.2 V vs. Ag/Ag+. [ABSTRACT FROM AUTHOR]

A NiB binary catalyst with a unique mulberry-like nanoparticle morphology has been prepared by one-step electrodeposition. The NiB-0.2 catalyst exhibits excellent catalytic activity, selectivity, and stability for the borohydride oxidation reaction. Moreover, a direct borohydride fuel cell using the NiB-0.2 catalyst anode can deliver a peak power density of 453 mW cm−2 and open-circuit voltage of 1.96 V at 343 K. The improved performances are due to the introduction of B. This study may inspire the development of efficient noble-metal-free anode catalysts for DBFCs. [ABSTRACT FROM AUTHOR]

Correction for 'Cu2O template synthesis of high-performance PtCu alloy yolk–shell cube catalysts for direct methanol fuel cells' by Sheng-Hua Ye et al., Chem. Commun., 2014, 50, 12337–12340, DOI: 10.1039/C4CC04108A. [ABSTRACT FROM AUTHOR]

Here we report on chelating ligands for Signal Amplification By Reversible Exchange (SABRE) catalysts that permit hyperpolarisation on otherwise sterically hindered substrates. We demonstrate 1H enhancements of ∼100-fold over 8.5 T thermal for 2-substituted pyridines, and smaller, yet significant enhancements for provitamin B6 and caffeine. We also show 15N-enhancements of ∼1000-fold and 19F-enhancements of 30-fold. [ABSTRACT FROM AUTHOR]

Construction of artificial photosynthetic systems including CO2 reduction is a promising pathway to produce carbon-neutral fuels and mitigate the greenhouse effect concurrently. However, the exploitation of earth-abundant catalysts for photocatalytic CO2 reduction remains a fundamental challenge, which can be assisted by a systematic summary focusing on a specific catalyst family. Cobalt-based complexes featuring tripodal ligands should merit more insightful discussion and summarization, as they are one of the most examined catalyst families for CO2 photoreduction. In this feature article, the key developments of cobalt-based tripodal complexes as molecular catalysts for light-driven CO2 reduction are discussed to offer an upcoming perspective, analyzing the present progress in electronic/steric tuning through ligand modification and dinuclear design to achieve a synergistic effect, as well as the bottlenecks for further development. [ABSTRACT FROM AUTHOR]

Converting CO2 to liquid (C5+) hydrocarbons remains a significant hurdle. Our study shows that CoFe/HZSM-5 boosts C5+ selectivity to 73.4%, up from 59% for Fe/HZSM-5. This study highlights the pivotal roles of zeolite acidity and catalyst proximity in this improvement. These insights pave the way for more effective CO2 utilization. [ABSTRACT FROM AUTHOR]

The article discusses the use of CO2 as an oxidant for the light-assisted oxidation of aldehydes to carboxylic acids. The authors question the validity of the results presented by S. L. Jain et al. and argue that the use of CO2 as an oxidant for aldehyde oxidation is questionable based on previous literature. They also raise concerns about the thermodynamic feasibility of the reaction. The authors suggest that further research is needed to develop more efficient and sustainable methods for aldehyde oxidation. [Extracted from the article]

Developing efficient electrocatalysts for CO2 reduction to syngas with tunable H2/CO ratios and high total faradaic efficiency is challenging. Herein, we report an effective catalyst composed of in situ reconstructed AgZn3 nanoparticles and Zn nanoplates for syngas synthesis, showing nearly 100% Faraday efficiency to syngas with a tunable H2/CO ratio from 2 : 1 to 1 : 2. Moreover, the in situ electrochemical measurements coupled with theoretical calculations disclose that the Zn site in AgZn3 nanoparticles and the hollow site between Ag and Zn in AgZn3 are the possible active sites for CO and H2 generation, respectively. This work has guiding significance for designing dual site catalysts for CO2 electroreduction to tunable syngas. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (CO2RR) to renewable fuels/chemicals is a potential approach towards addressing the carbon neutral economy. To date, a comprehensive analysis of key performance indicators, such as an intrinsic property of catalyst, reaction environment and technological advancement in the flow cell, is limited. In this study, we discuss how the design of catalyst material, electrolyte and engineering gas diffusion electrode (GDE) could affect the CO2RR in a gas-fed flow cell. Significant emphasis is given to scale-up requirements, such as promising catalysts with a partial current density of ≥100 mA cm−2 and high faradaic efficiency. Additional experimental hurdles and their potential solutions, as well as the best available protocols for data acquisition for catalyst activity evaluation, are listed. We believe this manuscript provides some insights into the making of catalysts and electrolytes in a rational manner along with the engineering of GDEs towards CO2RR. [ABSTRACT FROM AUTHOR]

We report SmCoO3 nanofibers as an efficient catalyst for nitrate reduction to ammonia. This catalyst achieves a large NH3 yield of 14.4 mg h−1 mgcat.−1 and a high faradaic efficiency of 81.3% at −1.0 V vs. RHE in 0.1 M PBS with 0.1 M NaNO3, and it also displays excellent electrochemical durability and structural stability. Theoretical calculations indicate that Sm–O and Co–O bonds have an incredibly low adsorption energy of −0.1 eV, which can significantly reduce the applied potential and hence enhance the catalytic activity. [ABSTRACT FROM AUTHOR]

In this work, three commercial Cu catalysts were benchmarked in the CO2RR using a gas-diffusion type microfluidic flow electrolyzer. We showed that commercial Cu could deliver a high FE of near 80% for C2+ product formations at 300 mA cm−2. By tuning the catalyst loading, a high reaction rate of near 1 A cm−2 with a C2+ product FE over 70% was achieved. Our results demonstrated that commercial Cu could achieve similar or better performances compared to many current catalysts by design in the CO2RR using similar electrolyzers. In addition, we showed that high CO reduction reaction (CORR) performance could also be achieved on commercial Cu, and disparities between CO and CO2 electrolysis were discussed. [ABSTRACT FROM AUTHOR]

This paper provides a viable, reproducible and robust method for immobilising hydroxyl tethered iridium–rhodium complexes. The materials have been shown to be both effective and recyclable in the process of catalytic transfer hydrogenation with minimal metal leaching. [ABSTRACT FROM AUTHOR]

To mimic enzymes in nature, a set of hybrid nanoarrays of Cu-MOFs sealed in hydrogen-substituted graphdiyne has been developed in order to serve as Lewis-acid-promoted catalysts. By regulating the electron-withdrawing capability of the ligands bridging Cu2+ sites, these Cu-MOFs provided different levels of Lewis acidity toward nitrate affinity, a feature crucial for nitrate-to-ammonia conversion. [ABSTRACT FROM AUTHOR]

The excessive emission of CO2 derived from the consumption of fossil fuels has caused severe energy and environmental crises. The electrochemical reduction of CO2 into value-added products such as CO not only reduces the CO2 concentration in the atmosphere but also promotes sustainable development in chemical engineering. Thus, tremendous work has been devoted to developing highly efficient catalysts for the selective CO2 reduction reaction (CO2RR). Recently, MOF-derived transition metal-based catalysts have shown great potential for the CO2RR due to their various compositions, adjustable structures, competitive ability, and acceptable cost. Herein, based on our work, a mini-review is proposed for an MOF-derived transition metal-based catalyst for the electrochemical reduction of CO2 to CO. The catalytic mechanism of the CO2RR was first introduced, and then we summarized and analyzed the MOF-derived transition metal-based catalysts in terms of MOF-derived single atomic metal-based catalysts and MOF-derived metal nanoparticle-based catalysts. Finally, we present the challenges and perspectives for the subject topic. Hopefully, this review could be helpful and instructive for the design and application of MOF-derived transition metal-based catalysts for the selective CO2RR to CO. [ABSTRACT FROM AUTHOR]

Designing catalysts is a challenging matter as catalysts are involved with various factors that impact synthesis, catalysts, reactor and reaction. In order to overcome these difficulties, catalysts informatics is proposed as an alternative way to design and understand catalysts. The underlying concept of catalysts informatics is to design the catalysts from trends and patterns found in catalysts data. Here, three key concepts are introduced: experimental catalysts database, knowledge extraction from catalyst data via data science, and a catalysts informatics platform. Methane oxidation is chosen as a prototype reaction for demonstrating various aspects of catalysts informatics. This work summarizes how catalysts informatics plays a role in catalyst design. The work covers big data generation via high throughput experiments, machine learning, catalysts network method, catalyst design from small data, catalysts informatics platform, and the future of catalysts informatics via ontology. Thus, the proposed catalysts informatics would help innovate how catalysts can be designed and understood. [ABSTRACT FROM AUTHOR]

A copper-catalyzed, redox-neutral cascade difluoroalkylation/5-endo annulation/β-fluorine cleavage of ynones is developed, providing a direct and stereoselective method to access synthetically important α-monofluoroalkenyl cyclopentanones. Mechanistic studies suggest an unprecedented CuII-assisted β-fluorine fragmentation, which may be valuable for the challenging but important C–F bond activation. Moreover, the in situ generated difluorocarbene was found to serve as an effective reductant for the regeneration of copper(I) catalyst, thus avoiding the addition of external reductants. [ABSTRACT FROM AUTHOR]

Nickel(0) nanoparticles coordinated to NHC ligands bearing N-coordinated cinnamyl moieties were readily prepared by reduction of a [NiCpBr(NHC-cinnamyl)] complex with methyl magnesium bromide. The combination of a strong σ-donor NHC ligand with a π-coordinating appended cinnamyl moiety likely prevents nickel(0) nanoparticle aggregation to larger inactive species, and allows the effective and (Z)-selective semi-hydrogenation of alkynes and ynamides. [ABSTRACT FROM AUTHOR]