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In the electrocatalytic CO2 reduction reaction (CO2RR), metal catalysts with an oxidation state generally demonstrate more favorable catalytic activity and selectivity than their corresponding metallic counterparts. However, the persistence of oxidative metal sites under reductive potentials is challenging since the transition to metallic states inevitably leads to catalytic degradation. Herein, a thorough review of research on oxidation-state stabilization in the CO2RR is presented, starting from fundamental concepts and highlighting the importance of oxidation state stabilization while revealing the relevance of dynamic oxidation states in product distribution. Subsequently, the functional mechanisms of various oxidation-state protection strategies are explained in detail, and in situ detection techniques are discussed. Finally, the prevailing and prospective challenges associated with oxidation-state protection research are discussed, identifying innovative opportunities for mechanistic insights, technology upgrades, and industrial platforms to enable the commercialization of the CO2RR. [ABSTRACT FROM AUTHOR]

The availability of catalytic sites for contact with reactants is a key issue to improve the performance of a catalyst, where constructing hollow structured nanomaterials has been considered as an effective strategy. Here, an N-doped carbon supported Ru catalyst with an interior cavity was synthesized by etching a MOF-derived core–shell precursor, in which metal Ru can be highly dispersed in the porous shell. This catalyst shows 98.7% conversion and >99% selectivity towards p-chloroaniline in the hydrogenation of p-chloronitrobenzene, which is better than the corresponding supported catalyst. Moreover, it also displays excellent stability with 5 cycle runs and good substrate universality for the hydrogenation of extensive substituted nitroarenes. Various characterization techniques and control experiments reveal the advantage of the unique structure to promote the mass transport and adsorption of reactant molecules on Ru sites. This work provides a novel strategy to design an efficient Ru-based catalyst for chemoselective hydrogenation. [ABSTRACT FROM AUTHOR]

The electrochemical alcohol oxidation reaction (AOR) is pivotal for the development of sustainable energy. The complete oxidation of alcohols has attracted extensive attention as a vital process in fuel cells. Moreover, as an alternative reaction to the oxygen evolution reaction, the selective oxidation of alcohols emerges as an effective means to lower the energy expenditure associated with electrolytic hydrogen production while yielding high‐value products. Nonprecious metal materials have been widely applied in the selective oxidation catalysis of alcohols due to their cost‐effectiveness and excellent durability. In recent years, leveraging the advantages of nonprecious metal materials in electrocatalytic AOR, researchers have delved into catalytic mechanisms and various efficient catalysts have been fabricated and evaluated. This review provides an overview of the current advancements in the electrocatalytic selective oxidation of diverse alcohols and the catalytic systems centered around nonprecious metal materials. It systematically summarizes the shared traits and distinctions in catalytic reaction characteristics across various systems, thereby laying the theoretical foundation for developing novel catalyst systems that are efficient, stable, and highly selective. This review will facilitate the utilization of nonprecious metal catalysts further toward the electrocatalytic oxidation of alcohols. [ABSTRACT FROM AUTHOR]

Plasma etching treatment is an effective strategy to improve the electrocatalytic activity, but the improvement mechanism is still unclear. In this work, a nitrogen‐doped carbon nanotube‐encased iron nanoparticles (Fe@NCNT) catalyst is synthesized as the model catalyst, followed by plasma etching treatment with different parameters. The electrocatalytic activity improvement mechanism of the plasma etching treatment is revealed by combining the physicochemical characterizations and electrochemical results. As a result, highly active metal–nitrogen species introduced by nitrogen plasma etching treatment are recognized as the main contribution to the improved electrocatalytic activity, and the defects induced by plasma etching treatment also contribute to the improvement of the electrocatalytic activity. In addition, the prepared catalyst also demonstrates superior ORR activity and stability than the commercial Pt/C catalyst. [ABSTRACT FROM AUTHOR]

The lateral size of graphene nanosheets plays a critical role in the properties and microstructure of 3D graphene as well as their application as supports of electrocatalysts for CO2 reduction reactions (CRRs). Here, graphene oxide (GO) nanosheets with different lateral sizes (1.5, 5, and 14 µm) were utilized as building blocks for 3D graphene aerogel (GA) to research the size effects of GO on the CRR performances of 3D Au/GA catalysts. It was found that GO-L (14 µm) led to the formation of GA with large pores and a low surface area and that GO-S (1.5 µm) induced the formation of GA with a thicker wall and isolated pores, which were not conducive to the mass transfer of CO2 or its interaction with catalysts. Au/GA constructed with a suitable-sized GO (5 µm) exhibited a hierarchical porous network and the highest surface area and conductivity. As a result, Au/GA-M exhibited the highest Faradaic efficiency (FE) of CO (FECO = 81%) and CO/H2 ratio at −0.82 V (vs. a Reversible Hydrogen Electrode (RHE)). This study indicates that for 3D GA-supported catalysts, there is a balance between the improvement of conductivity, the adsorption capacity of CO2, and the inhibition of the hydrogen evolution reaction (HER) during the CRR, which is related to the lateral size of GO. [ABSTRACT FROM AUTHOR]

Here, we for the first time introduce ethoxylation chemistry to develop a new octupolar cyano‐vinylene‐linked 2D polymer framework (Cyano‐OCF‐EO) capable of acting as efficient mixed electron/ion conductors and metal‐free sulfur evolution catalysts for dual‐promoted Li and S electrochemistry. Our strategy creates a unique interconnected network of strongly‐coupled donor 3‐(acceptor‐core) octupoles in Cyano‐OCF‐EO, affording enhanced intramolecular charge transfer, substantial active sites and crowded open channels. This enables Cyano‐OCF‐EO as a new versatile separator modifier, which endows the modified separator with superior catalytic activity for sulfur conversion and rapid Li ion conduction with the high Li+ transference number up to 0.94. Thus, the incorporation of Cyano‐OCF‐EO can concurrently regulate sulfur redox reactions and Li‐ion flux in Li−S cells, attaining boosted bidirectional redox kinetics, inhibited polysulfide shuttle and dendrite‐free Li anodes. The Cyano‐OCF‐EO‐involved Li−S cell is endowed with excellent overall electrochemical performance especially large areal capacity of 7.5 mAh cm−2 at high sulfur loading of 8.7 mg cm−2. Mechanistic studies unveil the dominant multi‐promoting effect of the triethoxylation on electron and ion conduction, polysulfide adsorption and catalytic conversion as well as previously‐unexplored −CN/C−O dual‐site synergistic effect for enhanced polysulfide adsorption and reduced energy barrier toward Li2S conversion. [ABSTRACT FROM AUTHOR]

The stability of Rh-based heterogeneous catalysts is a key issue in the hydroformylation of olefins. Confinement of active Rh species has been considered an effective strategy to achieve stable catalysts. In this work, a phosphine ligand was successfully confined in ZIF-8 material and coordinated with Rh metal by a reduction procedure to develop an efficient and stable Rh-based catalyst for hydroformylation of 1-octene. The results indicate that the catalyst reduced at 300 °C under H2 atmosphere exhibits better stability than that with NaBH4 as reductant and undoped P catalyst. Various characterization studies demonstrate that the superior performance is due to the strong interaction between Rh metal and P, which inhibits the leaching of active Rh species. This work reveals an effective strategy for the synthesis of highly stable catalysts for use in the hydroformylation reaction. [ABSTRACT FROM AUTHOR]

A series of interlaced 'tripe-shaped' nanoflake catalysts made of CuMn2O4 were in situ prepared on Ti mesh substrate through the associated methods of plasma electrolyte oxidation and hydrothermal technique. The surface morphology, elemental distribution and chemical state, phase composition and microstructure of CuMn2O4 nanostructures prepared under different conditions were systemically investigated. To evaluate the catalytic activity, the CO oxidation as a probe reaction was used, and the results showed that 12h-Cu1Mn2-300 (hydrothermal reaction at 150 °C for 12 h, Cu/Mn = 1/2 in initial precursor, heat treatment temperature at 300 °C) exhibited the best CO oxidation capability with T 100 = 150 °C owe to the formation of uniform CuMn2O4 nanosheet layers in situ grown on flexible Ti mesh and the synergistic effect of Cu and Mn species in spinel CuMn2O4, which makes it more active towards CO oxidation than pure copper/manganese oxides. [ABSTRACT FROM AUTHOR]

Composition-varied Au/PtTe hetero-junction-abundant nanostructures are fabricated by combining interfacial self-assembly and interface-confined transformation strategy, and can be directly used as electrocatalysts of boosting ethanol electrooxidation. [Display omitted] Pt-based multi-metallic electrocatalysts containing hetero-junctions are found to have superior catalytic performance to composition-equivalent counterparts. However, in bulk solution, controllable preparation of Pt-based hetero-junction electrocatalyst is an extremely random work owing to the complexity of solution reactions. Herein, we develop an interface-confined transformation strategy, subtly achieving Au/PtTe hetero-junction-abundant nanostructures by employing interfacial Te nanowires as sacrificing templates. By controlling the reaction conditions, composition-varied Au/PtTe can be easily obtained, such as Au 75 /Pt 20 Te 5 , Au 55 /Pt 34 Te 11 , and Au 5 /Pt 69 Te 26. Moreover, each Au/PtTe hetero-junction nanostructure appears to be an array consisting of side-by-side Au/PtTe nanotrough units and can be directly used as a catalyst layer without further post-treatment. All Au/PtTe hetero-junction nanostructures show better catalytic activity towards ethanol electrooxidation than commercial Pt/C because of the combining contributions of Au/Pt hetero-junctions and the collective effects of multi-metallic elements, where Au 75 /Pt 20 Te 5 exhibits the best electrocatalytic performance among three Au/PtTe nanostructures owing to its optimal composition. This study may provide technically feasible guidance for further maximizing the catalytic activity of Pt-based hybrid catalysts. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is an important chemical with a diverse array of applications. However, the existing scenario of centralized high-concentration production is in contrast with the demand for low-concentration decentralized production. In this context, the on-site green and efficient two-electron oxygen reduction reaction (ORR) for H2O2 production has developed into a promising synthetic approach. The development of low-cost, highly active, and durable advanced catalysts is the core requirement for realizing this approach. In recent years, single-atom catalysts (SACs) have become a research hotspot owing to their maximum atom utilization efficiency, tunable electronic structure, and exceptional catalytic performance. The coordination engineering of SACs is one of the key strategies to unlock their full potential for electrocatalytic H2O2 synthesis and holds significant research value. Despite considerable efforts, precisely controlling the electronic structure of active sites in SACs remains challenging. Therefore, this review summarizes the latest progress in coordination engineering strategies for SACs, aiming to elucidate the relevance between structure and performance. Our goal is to provide valuable guidance and insights to aid in the design and development of high-performance SACs for electrocatalytic H2O2 synthesis. [ABSTRACT FROM AUTHOR]

The efficient conversion of CO2 to value‐added products represents one of the most attractive solutions to mitigate climate change and tackle the associated environmental issues. In particular, electrochemical CO2 reduction to fuels and chemicals has garnered tremendous interest over the last decades. Among all products from CO2 reduction, formic acid is considered one of the most economically vital CO2 reduction products. P‐block metals (especially Bi, Sn, In, and Pb) have been extensively investigated and recognized as the most efficient catalytic materials for the CO2 electroreduction to formate. Despite remarkable progress, the future implementation of this technology at the industrial‐scale hinges on the ability to solve remaining roadblocks. In this review, the current research status, challenges, and prospects of p‐block metal‐based catalysts primarily for CO2 electroreduction to formate are comprehensively reviewed. The rational design and nanostructure engineering of these p‐block metal catalysts for the optimization of their electrochemical performances are discussed in detail. Subsequently, the recent progress in the development of state‐of‐the‐art operando characterization techniques together with the design of advanced electrochemical cells to uncover the intrinsic catalysis mechanism is discussed. Lastly, a perspective on future directions including tackling critical challenges to realize its early industrial implementation is presented. [ABSTRACT FROM AUTHOR]

Binary single‐atom catalysts (BSACs) have demonstrated fascinating activities compared to single atom catalysts (SACs) for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Notably, Fe SACs is one of the most promising ORR electrocatalysts, and further revealing the synergistic effects between Fe and other 3d transition metals (M) for FeM BSACs are very important to enhance bifunctional performance. Herein, density functional theory (DFT) calculations are first adapted to demonstrate the role of various transition metals on the bifunctional activity of Fe sites, and a notable volcano relationship is established through the generally accepted adsorption free energy that ΔG*OH for ORR, and ΔG*O−ΔG*OH for OER, respectively. Further, ten of the atomically dispersed FeM anchored on nitrogen‐carbon support (FeM‐NC) are successfully synthesized with typical atomic dispersion by a facile movable type printing method. The experimental data confirms the bifunctional activity diversity of FeM‐NC between the early‐ and late‐ transition metals, agrees very well with the DFT results. More importantly, the optimal FeCu‐NC shows the expected performance with high ORR and OER activity, thereby, the assembled rechargeable zinc–air battery delivers a high power density of 231 mW cm−2, and an impressive stability that can be stably operated over 300 h. [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]

CO2 hydrogenation to methanol was conducted using a set of activated carbon-supported Cu/ZnO/Al2O3 catalysts (CCZA) prepared by an incipient wetness impregnation approach. The effect of the Cu/Al ratio on the physicochemical properties of the catalysts, as well as their catalytic performance, were investigated. As Cu/Al ratio increased, the metallic Cu surface area displayed a reducing trend from 6.88 to 4.18 m2∙gcat−1, while the CO2 adsorption capacity exhibited an increasing trend. Meanwhile, aluminum content will have an important effect on the catalysts' reducibility and, thus, on their catalytic performance. The CCZA-2.7-de catalyst demonstrated the highest selectivity to methanol at 83.75% due to the excellent distribution and synergistic effect of copper and zinc. Although the CO2 conversion of CCZA-2.2-de and CCZA-3.5-de exceeded 10%, the CH3OH selectivity was less than 60%, which may be attributed to the larger particle sizes of ZnO and poor interactions in Cu–Zn. The present study offers a novel approach to increase the number of active sites, optimize the activated carbon-aided Cu/ZnO/Al2O3 catalyst's composition, and finally elucidate the mechanism for CO2 hydrogenation to methanol. [ABSTRACT FROM AUTHOR]

Herein, atomically dispersed Ni–N 3 –C materials are facilely synthesized by the pyrolysis of Ni-doped ZIF-8. Each single Ni atom is proved to be bonded with three N atoms to form Ni–N 3 sites by X-ray absorption spectroscopy. During the pyrolysis at high temperature, the increasing of relative contents and blue-shift binding energy of pyrrolic N can be observed, indicating the Ni might be bonded with pyrrolic N. Moreover, the formation energy (E f) of NiN 3 -pyrrolic structure is smaller than that of NiN 3 -pyridinic calculated by density functional theory (DFT), thus confirming the dominated bonding structure of NiN 3 -pyrrolic further. The optimum material can achieve an ultra-high CO Faradaic efficiency of 99.37% at −0.75 V vs. RHE with a turnover frequency (TOF) of 3498 h−1 and a high CO partial current density of 80 mA cm−2 at −1.15 V vs. RHE, which is among the best Ni catalysts. Based on DFT results, the NiN 3 -pyrrolic sites can facilitate both the formation of COOH* intermediate and desorption of CO, which can also suppress the competitive hydrogen evolution reaction (HER) simultaneously, thus resulting in high catalytic activity and selectivity from CO 2 to CO. Electroreduction from CO 2 to CO with high activity and selectivity are achieved on the single-atom Ni–N–C catalyst due to the dominated Ni coordination structure by three pyrrolic N atoms. [Display omitted] • Single Ni atom catalysts were synthesized with Ni-doped ZIF-8 as precursor. • NiN 3 -pyrrolic coordination structure was identified as the dominated active sites. • Ultra-high activity and selectivity for CO 2 reduction towards CO was achieved. • NiN 3 -pyrrolic sites can promote the formation of *COOH intermediate by DFT. [ABSTRACT FROM AUTHOR]

Thermal spray coatings have the advantage of providing thick and functional coatings from a range of engineering materials. The associated coating processes provide good control of coating thickness, morphology, microstructure, pore size and porosity, and residual strain in the coatings through selection of suitable process parameters for any coating material of interest. This review consolidates scarce literature on thermally sprayed components which are critical and vital constituents (e. g., catalysts (anode/cathode), solid electrolyte, and transport layer, including corrosion‐prone parts such as bipolar plates) of the water splitting electrolysis process for hydrogen production. The research shows that there is a gap in thermally sprayed feedstock material selection strategy as well as in addressing modelling needs that can be crucial to advancing applications exploiting their catalytic and corrosion‐resistant properties to split water for hydrogen production. Due to readily scalable production enabled by thermal spray techniques, this manufacturing route bears potential to dominate the sustainable electrolyser technologies in the future. While the well‐established thermal spray coating variants may have certain limitations in the manner they are currently practiced, deployment of both conventional and novel thermal spray approaches (suspension, solution, hybrid) is clearly promising for targeted development of electrolysers. [ABSTRACT FROM AUTHOR]

Efficient and sustainable chemical fixation of CO2 into value-added chemicals is one of the most promising objectives in environmental chemistry. In this work, transition metal acetylacetonate immobilized onto triazolium ionic liquid-modified periodic mesoporous organosilica PMO-IL-M(x) was successfully prepared and investigated as an effective and heterogeneous catalyst in the direct carboxylation of terminal alkynes and CO2 to the desired alkynyl carboxylic acids. It was found that the catalyst PMO-IL-Sn(0.3) exhibited extraordinary catalytic performance in terms of excellent activity, stability, productivity, and excellent yields under mild reaction conditions. Moreover, the catalyst PMO-IL-Sn(0.3) could be easily recovered and reused at least six times without considerable loss in catalytic activity. This work provides a sustainable and efficient synergistic strategy for the chemical fixation of carbon dioxide into valuable alkynyl carboxylic acids. [ABSTRACT FROM AUTHOR]

In this paper, the effects of Zr, Al or Sr doped Mn/MCM-41 on NH3-SCR activity, SO2/H2O resistance and mechanism were studied. The results showed that Mn/Zr-MCM-41 has 100% NOx conversion at 175–300 °C while Mn/Al-MCM-41 achieves about 94% N2 selectivity at 120–400 °C. Zr doping significantly enhances the resistance to SO2 at 200 °C while Sr plays a negative role. Doped metal does not change the ordered hexagonal arrangement of MCM-41, but can cause the specific surface area enrichment of Mn while Al doping leads to the entry of Mn into the channel of MCM-41. Mn/MCM-41 has only Lewis acid sites, but Zr, Al or Sr doped catalysts have Lewis and Brønsted acid sites. Moreover, the reaction path on Mn/MCM-41 and Mn/Zr-MCM-41 mainly conforms to the L–H mechanism while Mn–Al or Mn–Sr doped catalysts follow L–H and E–R mechanisms. However, the deposited sulfates change the progress of the NH3-SCR process and cause a decline of SCR activity. [ABSTRACT FROM AUTHOR]

Zinc-air battery (ZAB) is a promising new metal-air energy system, but the large overpotentials of oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) around the air electrode lead to their poor energy efficiency. Herein, a novel bifunctional oxygen electrocatalyst is reported with the preparation of a zeolite imidazolate framework (ZIF-67) derived trimetallic composites decorated nitrogen-doped carbon, which consist of NiFe alloy and Co nanoparticles. The ZIF-derived porous N-doped carbon shell can speed up the mass transfer efficiency. Whereas the electronic effect between the formed NiFe alloy and Co nanoparticles, as well as the N-doped carbon framework can enrich the active centers and enhance the electrical conductivity. As a result, the NiFe-Co@NC-450 catalyst shows superior performance manifested as a small potential gap (Î" E  = 0.857 V) between the overpotential at 10 mA cmâˆ'2 (E j=10) for OER (460 mV) and half-wave potential (E 1/2) for ORR (0.833 V). The liquid ZABs exhibit a high specific capacity reaching 798 mAh/gZn and a stable cycling performance at 10 mA cmâˆ'2 for more than 200 h. Meanwhile, the NiFe-Co@NC-450 based flexible ZABs also presents robust flexibility and stability. This study has certain implications for the development of economical, powerful and stable bifunctional catalysts for ZABs. [ABSTRACT FROM AUTHOR]

The controllable anchoring of multiple isolated metal atoms into a single support exhibits scientific and technological opportunities, while the synthesis of catalysts with multiple single metal atoms remains a challenge and has been rarely reported. Herein, we present a general route for anchoring up to eleven metals as highly dispersed single-atom centers on porous nitride-doped carbon supports with the developed movable type printing method, and label them as high-entropy single-atom catalysts. Various high-entropy single-atom catalysts with tunable multicomponent are successfully synthesized with the same method by adjusting only the printing templates and carbonization parameters. To prove utility, quinary high-entropy single-atom catalysts (FeCoNiCuMn) is investigated as oxygen reduction reaction catalyst with much more positive activity and durability than commercial Pt/C catalyst. This work broadens the family of single-atom catalysts and opens a way to investigate highly efficient single-atom catalysts with multiple compositions. It is challenging to integrate multi-single metal atoms into one support. In this work, the authors demonstrate the production of high-entropy single-atom catalysts via a movable typing method, which enables the anchor up to eleven metals as highly dispersed single-atom active centers on the carbon support for the oxygen reduction reaction. [ABSTRACT FROM AUTHOR]

Amorphous catalysts have a large number of catalytic active sites. Here, we report a magnesium composite trace lanthanum catalyst (La@Mg), in which La and Mg layers form amorphous Mg–La compound on the surface of layered Mg. The test shows this La@Mg has hydrogen storage capacity of about 7.6 wt% and hydrogen desorption of 7.2 wt%, higher than that of crystalline La@Mg and sole Mg, rapid absorption/desorption kinetic and stable reversible absorption/desorption cycles. La@Mg exhibits an optimistic hydrogen storage performance than Mg-based materials previously reported in the literature. Combined with theoretical calculations, it is shown that the amorphous Mg–La has an catalysis on hydrogen storage performance of La@Mg system, which contributing to the dispersion of Mg and providing channels for hydrogen diffusion, facilitating hydrogenation by accelerating H atoms diffuse between the subsurface and the surface. This work provides experiment and mechanism guidance for the development of efficient hydrogen storage materials. • The amorphous La@Mg catalyst was rationally synthesized. • The La@Mg has a hydrogen storage capacity of 7.6 wt% and reversible hydrogen absorption/desorption. • The content of amorphous LaMg was increased and it was conducive to the hydrogen absorption. [ABSTRACT FROM AUTHOR]

Developing readily scalable synthesis techniques for electrocatalysts is highly desirable for large-scale high-efficiency energy storage by water electrolysis. In this work, a coupled procedure of direct electrodeposition and in situ chemical transformation is presented to synthesize a nickel-iron-sulfur (Ni–Fe–S) composite catalyst. A polythiophene (PTh) coating with abundant micro/nano holes is directly deposited on graphite electrode at a constant potential. Two precursor solutions were injected onto and completely absorbed by the porous PTh coating, within which they spontaneously combine to form active species for catalysis. The PTh coating functions as a monolithic conductive matrix that well captures and disperses the catalyst species and thus decreases the contact resistance across the phase interfaces. The prepared catalyst shows a high catalytic performance for both hydrogen and oxygen evolution reactions. It requires a full cell voltage of about 2.0 V to afford a current density of 100 mA cm−2 in 1.0 M KOH, with no activity degradation at least for 24 h. The active species for the cathodic and anodic catalysis are different and discussed separately. This work indicates that in situ chemical synthesis within a porous conductive polymer coating is a promising approach for preparing high efficiency electrocatalysts. [Display omitted] • Abundant micro/nano holes inside polythiophene coating working as microreactors. • Rapid formation of catalyst active species within microreactors. • Monolithic conducting matrix well capturing and dispersing active species. • A single catalyst but different active species for HER and OER catalysis. [ABSTRACT FROM AUTHOR]

Lignin is an attractive renewable source of aromatics with a low effective hydrogen to carbon ratio (H/Ceff). The catalytic hydrodeoxygenation (HDO) of lignin-derived model compounds is a key strategy for lignin upgrading. In this work, the HDO of guaiacol, a typical lignin-derived compound, was carried out over metal–organic framework (MOF)-derived Ni-based catalysts. A monometallic Ni-MOF catalyst and different ratios of bimetallic NiMo-MOF catalysts were synthesized by a hydrothermal process, followed by a carbonization process. Among these catalysts, Ni3Mo1@C exhibited an excellent catalytic performance, affording a guaiacol conversion of 98.8% and a cyclohexanol selectivity of 66.8% at 240 °C and 2 MPa H2 for 4 h. The addition of Mo decreased the particle size of the spherical structure and improved the dispersion of metal particles. The synergistic effect between Ni and Mo was confirmed by various means, including ICP, XRD, SEM, TEM, and NH3-TPD analyses. In addition, the effect of the reaction temperature, time, and H2 pressure during the HDO process is discussed in detail. [ABSTRACT FROM AUTHOR]

Fe-SiO 2 interaction is a critical issue in the study of Fischer-Tropsch Fe/SiO 2 catalyst. It has been advanced that the formation of Fe-O-Si bond is related to Fe-SiO 2 interaction and responsible for dispersing iron particles and stabilizing active phases. This work formulates studying the relationship and interconversion between Fe-O-Si bond and Fe 2 SiO 4 phase, and further concludes that Fe 2 SiO 4 is another form of Fe-SiO 2 interaction. A well mixing of Fe-O and Si-O domains in the catalyst precursor benefits the distribution of extensive Fe-O-Si bond, which in turn facilitates the formation of Fe 2 SiO 4 during the catalyst reduction process. High ramp rate and diluted H 2 favor the transition of discrete Fe-O-Si to Fe 2 SiO 4 kinetically and thermodynamically, respectively. During the transition, amorphous Fe 2 SiO 4 initially forms before undergoing a rapid crystallization process, at ca. 560 ± 10 °C, to transform to large crystals detectable by XRD. In addition, the amorphous nature of Fe 2 SiO 4 requires the combination of characterization techniques capable of detecting short-range ordered structures, e.g., XAFS, MES, and magnetometer. [Display omitted] • Fe 2 SiO 4 is another form of Fe-SiO 2 interaction for Fischer-Tropsch Fe/SiO 2 catalyst. • Well distributed Fe-O-Si bond can transform to amorphous Fe 2 SiO 4. • High ramp rate and diluted H 2 kinetically favor the transition of Fe-O-Si to Fe 2 SiO 4. • Amorphous Fe 2 SiO 4 undergoes rapid crystallization process to form large particles at 560 ± 10 °C. • The dehydration of Si-OH facilitates the crystallization of Fe 2 SiO 4. [ABSTRACT FROM AUTHOR]

This article, titled "Understanding the improvement mechanism of plasma etching treatment on oxygen reduction reaction catalysts," explores the use of plasma etching as a method to synthesize and enhance the performance of electrocatalysts. The study reveals that the introduction of highly active metal-nitrogen species through nitrogen plasma etching treatment is the main factor contributing to the improved electrocatalytic activity. Additionally, the defects induced by plasma etching also play a role in the high performance of the catalysts. The authors of the article are Peng Rao, Yanhui Yu, Shaolei Wang, Yu Zhou, Xiao Wu, Ke Li, Anyuan Qi, Peilin Deng, Yonggang Cheng, Jing Li, Zhengpei Miao, and Xinlong Tian. [Extracted from the article]

The development of Ni-based catalysts with outstanding anti-coking ability is necessary for realizing the industrial application of dry reforming of CH 4 (DRM) to syngas. Here, a facile combustion method with unique characteristic was employed to prepare the Ni/SiO 2 catalyst with different promoters (ZrO 2 or Ru). The effects of Ni particle size and promoter (ZrO 2 or Ru) on the anti-coking ability of Ni/SiO 2 catalyst were examined. The XRD and TEM results showed that improved Ni dispersion can be obtained via the facile combustion method, accompanying with enhanced metal-support interaction and CO 2 adsorption capacity confirmed by H 2 -TPR and CO 2 -TPD, respectively. In comparison with Ni-IMP catalyst (prepared via the traditional impregnation method), the carbon deposition over Ni–C catalyst (prepared via the combustion method) decreased by 67% (from 2.7 to 0.9 mg carbon deposition ·g−1 CH4) as a result of the small Ni particles. The H 2 -TPR and XPS results revealed the interaction between promoter (ZrO 2 and Ru) and Ni. The addition of ZrO 2 can enhanced the CO 2 activation ability of catalyst and the formed oxygen species can facilitate the elimination of carbon species, further decreasing the carbon deposition compared with Ni–C catalyst. The best catalytic performance with least carbon deposition (only 0.4 mg carbon deposition ·g−1 CH4) is achieved on the NiRu–C catalyst. The slower CH 4 dissociation rate and the improved CO 2 activation benefited from Ru can bring in the better balance between the carbon formation and elimination, leading to the best anti-coking ability of catalyst. [Display omitted] • Highly dispersed Ni particles are obtained by a combustion method with low cost. • Excellent catalytic stability is achieved on the catalyst with small Ni particles. • ZrO 2 can enhance the CO 2 activation and facilitate the elimination of carbon species. • NiRu/SiO 2 catalyst can balance CH 4 and CO 2 activation, minimizing the coke formation. [ABSTRACT FROM AUTHOR]

A Co–zeolite imidazole ester framework (ZIF-67) has excellent electrochemical performance for the oxygen reduction reaction (ORR), but the structural stability is still the key problem to be solved. PEDOT is a polymer of EDOT (3,4-ethylenedioxythiophene monomer), a π-conjugated conductive polymer with superior performance and wide application. It has a rigid and linear conformation, which is necessary to maintain the integrity of the material structure and prevent collapse. And this conformation is also conducive to charge transport and crystallization, resulting in good performance of high charge/discharge capacities, fast response time and high sensing ability. Herein through the pre-implantation of PEDOT nanowires, the structural collapse, anisotropic shrinkage and Co atom agglomeration of ZIF-67 in the pyrolysis process were inhibited, and S,N co-doping was realized at the same time. The XRD, SEM, TEM and XPS characterization studies prove that PEDOT nanowires successfully embedded in the ZIF-67 structure, and N and S are doped into the carbon framework of the catalyst. The synthesized catalyst has a regular hexahedral morphology, interconnected three-dimensional (3D) nanowire (NW) framework and graphitized carbon coated Co nanoparticles (Co/C@NS NWs), endowing it with excellent bifunctional catalytic performance toward oxygen. The initial potential was 0.91 V (vs. RHE) and the limiting current density was −4.8 mA cm−2 for the ORR. The potential required to reach 10 mA cm−2 is only 1.55 V (vs. RHE) and the Tafel slope for the oxygen evolution reaction (OER) is relatively low (100 mV dec−1). An open circuit voltage of 1.46 V for Zn–air battery cathodes catalyzed by Co/C@NS NWs at a discharge power density of 129.3 mWcm−2 is obtained, and the specific capacity at a discharge current density of 10 mA cm−1 is 800 mA h gZn−1. The voltages show no obvious change for a 35 h continuous discharge/charge cycle experiment. Therefore, this work provides a new inspiration for the design and development of high-performance non-noble metal carbon-based bifunctional oxygen electrocatalysts. [ABSTRACT FROM AUTHOR]

• Providing a new strategy for preparation of dual/ multivariate single-atoms electrocatalyst. • Designing a dual single-atoms electrocatalyst TaCo-N-C. • The photovoltaic performanceof TaCo-N-C-based DSSC exceeds that of Pt-based DSSC. • Presenting an theoretical understanding of synergistic effect between dual single-atom. This study aims to design a dual single-atom electrocatalyst (DSAC) and elucidate the synergistic effect mechanism between DSAs. A novel synthetic strategy, combining ZIF pyrolysis and ionexchange, is employed for fabricating DSA electrocatalyst. A new type of electrocatalyst of TaCo-N-C containing dual atomically dispersed activity sitesis first obtained. Its intrinsic activity is investigated experimentally and rivals that of Pt. The adsorption energies of activity moieties are computated by first-principle density functional theory (DFT) to give synergistic effect description. Co-adsorption enhances catalytic activity by decreasing adsorption energy. This work provides an ideal alternative to Pt and a new idea for the preparation of dual/multivariate single-atom electrocatalysts and presents an atomic scale mechanism understanding of synergistic effect, which is a predictive guideline for the rational design of new types of electrocatalysts. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) are a highly efficient hydrogen energy conversion technology, which shows great potential in mitigating carbon emissions and the energy crisis. Currently, to accelerate the kinetics of the oxygen reduction reaction (ORR) required for PEMFCs, extensive utilization of expensive and rare platinum‐based catalysts are required at the cathodic side, impeding their large‐scale commercialization. In response to this issue, atomically dispersed metal–nitrogen–carbon (M–N–C) catalysts with cost‐effectiveness, encouraging activity, and unique advantages (e.g., homogeneous activity sites, high atom efficiency, and intrinsic activity) have been widely investigated. Considerable progress in this domain has been witnessed in the past decade. Herein, a comprehensive summary of recent development in atomically dispersed M–N–C catalysts for the ORR under acidic conditions and of their application in the membrane electrode assembly (MEA) of PEM fuel cells, are presented. The ORR mechanisms, composition, and operating principles of PEMFCs are introduced. Thereafter, atomically dispersed M–N–C catalysts towards improved acidic ORR and MEA performance is summarized in detail, and improvement strategies for MEA performance and stability are systematically analyzed. Finally, remaining challenges and significant research directions for design and development of high‐performance atomically dispersed M–N–C catalysts and MEA are discussed. [ABSTRACT FROM AUTHOR]

Low‐cost and efficient bifunctional catalysts are urgently needed for overall water splitting used in large‐scale energy storage. In this study, we develop a nickel and iron (di)sulfide (Ni−Fe−S) composite catalyst that is in situ synthesized and fixed within the intergranular nanopores inside high pure polycrystalline graphite. Two precursor solutions (reactants) may permeate the graphite intergranular pores to a depth of more than 3.5 mm. The nanoscale pores serve as an array of nanoreactors for the synthesis of the Ni−Fe−S nanoparticles under conditions much milder than usual. The prepared catalyst efficiently catalyzes both the hydrogen and oxygen evolution reactions (HER and OER) in 1.0 M KOH. It delivers a current density of 400 mA cm−2 at a full cell voltage of around 2.3 V without considerable activity decay over 24 h electrolysis. The active species of the catalyst are different for the HER and OER and discussed accordingly. The synthesis strategy based on the nanopores in a monolithic conductive substrate proves to be a simple, efficient, and promising way to prepare electrocatalysts that are cheap, abundant, and industrially attractive. [ABSTRACT FROM AUTHOR]

Microwave assisted lignin depolymerization was investigated over HSZ-supported CuNiAl-based catalysts. The synergistic effect between the acidic HSZ support and mixed metal oxides was studied in detail to explore the difference in catalytic activity during the lignin depolymerization process. Improvements in bio-oil properties, such as the H/C ratio and HHV value, were observed in comparison with raw lignin under rather mild conditions (140 °C, 80 min) in the absence of external hydrogen. The molecular weight of bio-oil obtained over HSZ-supported catalysts decreased, indicating that the increased acidity in the catalyst could facilitate microwave assisted lignin depolymerization. The product distributions in bio-oil were also analyzed and plausible depolymerization mechanisms were proposed considering the distributions of lignin-derived dimers/trimers and monomers. [ABSTRACT FROM AUTHOR]

An amphiphilic block copolymer PNIPAM53‐b‐(PS30‐co‐P4AMS10) was facilely prepared by reversible addition‐fragmentation chain transfer (RAFT) polymerization. The immobilization of (S)‐α,α‐diphenylprolinol trimethylsilyl ether onto the block copolymers was then performed through using copper‐catalyzed alkyne‐azide cycloaddition (CuAAC), and the generating amphiphilic diblock copolymer supported chiral catalyst PNIPAM53‐b‐(PS30‐co‐P4AMS10)/proTMS was self‐assembled into micelles with regular diameters about 50 nm in aqueous solution. The micellar catalyst was further used for the asymmetric Michael reaction between propanal and trans‐β‐nitrostyrene in water. Using only 1 mol% micellar catalyst, the corresponding Michael addition products could be obtained in good yields and high enantioselectivities as well as good diastereoselectivities. In addition, this micellar catalyst could be reused at least for four times. Moreover, the micellar catalyst could be applied for the asymmetric addition reaction of 4‐chlorocinnamyl aldehyde and nitromethane, and thus constructing the baclofen pharmaceutical intermediate. [ABSTRACT FROM AUTHOR]

This study reports on the development of highly-efficient Pt/CuO-Fe 2 O 3 /TiO 2 monolithic catalysts for the low-temperature conversion of NO to N 2 via CO-SCR. In this case, ultrathin TiO 2 nanosheet arrays are designed to in situ grow on flexible Ti mesh to provide more spaces/areas for the loading of highly-dispersed Fe 2 O 3 and CuO active components. Furthermore, Pt nanoparticles with an average size of 1.30 nm are effectively decorated on the surface of CuO-Fe 2 O 3 /TiO 2. The H 2 -TPR and NO-TPD results demonstrate that the excellent synergistic effect between TiO 2 , CuO, Fe 2 O 3 and trace amounts of Pt is conducive to enhance the adsorption of NO and finally promote the CO-SCR. The obtained Pt/CuO-Fe 2 O 3 /TiO 2 catalysts exhibit excellent CO-SCR performance with 100 % NO conversion, and 100 % N 2 selectivity at 250 °C, showing great potential of de-NO x application by using toxic CO as reductant in industry. [Display omitted] • Pt/CuO-Fe 2 O 3 /TiO 2 monolithic catalysts were in-situ grown on a Ti mesh. • Ultrathin TiO 2 nanosheet array facilitates the high loading of Fe 2 O 3 and CuO. • The decorated Pt nanoparticles facilitate the adsorption and reduction of NO. [ABSTRACT FROM AUTHOR]

Co, N co-doped carbon (CoN@C) with properly engineered heteropores was facilely synthesized using metal carbonate hydroxides as metal precursor and multistage porogen. CoN@C therefore exhibits superior ORR catalytic activity with a half-wave potential of 0.876 V vs. RHE, and the CoN@C-based zinc-air battery can be stably cycled for 100 h. [ABSTRACT FROM AUTHOR]

Rhenium disulfide (ReS2) as a catalyst is promising in water splitting for hydrogen evolution reaction (HER) owing to its unique structure and physiochemical property. Chemical vapor deposition (CVD) is one of effective means for the fabrication of high-crystallinity ReS2. At present, conductivities of typical substrates used for the CVD growth are mostly poor. The transfer to a conductive support or other engineering for improving the conductivity is necessarily required for the application of HER electrode. However, the damage to original structure and the introduction of impurities are highly possible in the process. The cost of time and material is also increased. In this work, we propose that a wood-derived carbon framework is used as a working electrode supporting CVD-grown ReS2 nanosheets in electrocatalytic HER. The optimal HER electrode with unique pore-through structure exhibits effective electrochemical surface area of 521 cmECSA2 and outstanding stability over 11 h. Such a carbon framework derived from natural wood is earth-abundant, ecofriendly and renewable, which can be potentially applied in the green energy industry. [ABSTRACT FROM AUTHOR]

Dioxo‐molybdenum complexes have been reported as catalysts for the deoxydehydration (DODH) of diols and polyols. Here, we report on the DODH of diols using [Cp*MoO2]2O as catalyst (Cp*=1,2,3,4,5‐pentamethylcyclopentadienyl). The DODH reaction was optimized using 2 mol % of [Cp*MoO2]2O, 1.1 equiv. of PPh3 as reductant, and anisole as solvent. Aliphatic vicinal diols are converted to the corresponding olefins by [Cp*MoO2]2O in up to 65 % yield (representing over 30 turnovers per catalyst) and 91 % olefin selectivity, which rivals the performance of other Mo‐based DODH catalysts. Remarkably, cis‐1,2‐cyclohexanediol, which is known as quite a challenging substrate for DODH catalysis, is converted to 30 % of 1‐cyclohexene under optimized reaction conditions. Overall, the mass balances (up to 79 %) and TONs per Mo achievable with [Cp*MoO2]2O are amongst the highest reported for molecular Mo‐based DODH catalysts. A number of experiments aimed at providing insight in the reaction mechanism of [Cp*MoO2]2O have led to the proposal of a catalytic pathway in which the [Cp*MoO2]2O catalyst reacts with the diol substrate to form a putative nonsymmetric dimeric diolate species, which is reduced in the next step at only one of its Mo‐centers before extrusion of the olefin product. [ABSTRACT FROM AUTHOR]

A type of multifunctional mesoporous SBA‐15 supported imidazolium ionic liquids SBA‐15@IL‐OAc have been designed and synthesized, characterized and tested as heterogeneous catalysts in the Knoevenagel condensation. The prepared catalysts exhibit good catalytic performances in the reaction at room temperature, especially the supported ionic liquid SBA‐15@IL‐OAc(0.8) with excellent yields of 90∼98 %, probably due to the synergetic effect between acetate anion sites of imidazolium ionic liquid and hydroxyl active sites of SBA‐15. In addition, the recyclability of the heterogeneous catalyst was tested, and the cycle test showed that the catalyst could be reused five times without significantly reducing the catalytic activity. [ABSTRACT FROM AUTHOR]

A facile boron doping strategy to improve the nitrogen retention in carbon-based catalysts is developed toward efficient oxygen reduction reaction via offsetting the electron migration. By considering the hetero-porous structure at the same time, this B, N co-doped catalyst outperforms commercial Pt/C in terms of both activity and stability. [ABSTRACT FROM AUTHOR]

Novel 3D P-doped poly(triazine imide) (PTI) nanotubes were prepared in situ by molten salt method with melamine and hexachlorotriphosphazene as starting precursors. The as-prepared composite showed superior photocatalytic properties under visible-light irradiation due to the integrated merits of 1D tubular structure, 1D nanorods, and P doping. The improved utilization of visible light and the enhanced separation of photo-induced charge carriers resulted in the maximum degradation rate constant of P-doped PTI at 2.86 min−1, which was approximately 6.3 and 2.6 folds those of bulk graphite-like carbon nitride and pristine PTI material, respectively, during tetracycline hydrochloride photodegradation. Moreover, the novel catalyst has an excellent stability and thus is a promising candidate for photocatalysis. [ABSTRACT FROM AUTHOR]

Searching a low‐cost and excellent performance catalyst for hydrogen evolution reaction (HER) is important for enhancing the efficiency of water splitting. In this manuscript, we report the Co, S co‐doped carbon‐framework supported MoO2 nanosheets (Co, S/MoO2−C) for HER. The carbon‐framework improves the distribution of the MoO2, which causes a large number of exposed active sites. The synergistic effect of Co and S enhances the electron transport of the MoO2. As a result, the Co, S/MoO2−C exhibits a low overpotential (62 mV vs. RHE) and enhanced stability in 1 M KOH for HER. Our work puts forward a novel method to improve the catalytic performance of MoO2 and provides a new option to prepare excellent catalysts. [ABSTRACT FROM AUTHOR]

For medium and low matured shale oil exploration, in situ upgrading could promote the oil recovery. There are two main disadvantages herein, high exploration temperature and large energy consumption. The new approach has been proposed to apply porous aluminosilicate catalysts for shale oil highly efficient upgrading at 350°C, H‐clin and Ni‐clin catalysts were prepared with natural clinoptilolite. Al‐SBA‐15 catalysts were synthesized by following one‐step crystallization procedure, and firstly employed for shale oil in situ upgrading. Kinetic studies of pyrolysis showed that the activation energy of organic matter conversion in shale was reduced from 113.80 kJ mol−1 to 37.28 kJ mol−1. After the catalyst addition, shale oil conversion temperature was declined, the reaction rate was increased, and the energy consumption of in situ upgrading was reduced. In Sinopec patented testing instrument, hydrocarbon generation and hydrocarbon expulsion unit, shale oil catalytic conversion showed increased hydrocarbon generation by 2%‐16%. Under the same reaction conditions, the Al‐SBA‐15 (Si/Al = 5) revealed the best activity for hydrocarbon generation, and the efficiency was elevated to 32.67%, twice as that of thermal conversion. The quality of catalytically produced oil was promoted, by improving the further cracking of bitumen to light oil and gas. The results have a breakthrough significance for intensifying the high‐efficiency hydrocarbon generation and expulsion process of low and medium matured shale oil. [ABSTRACT FROM AUTHOR]

With ethylene glycol as a green solvent, a general transition metal‐free photocatalytic system using 9‐mesityl‐10‐methylacridinium perchlorate (Acr+−Mes ⋅ ClO4−) as catalyst was developed for the synthesis of sulfone‐containing heterocycles including thioflavones, oxindoles, and quinoline‐2,4(1H,3H)‐diones through the cascade sulfonation/cyclization reactions under the irradiation of blue light at room temperature. [ABSTRACT FROM AUTHOR]

The development of advanced catalyst integration strategy is of great importance and promising for long‐term and stable gas catalysis in environmental processing. However, conventional catalyst fabrication techniques including spray method and spin coating cannot overcome the key problems of catalyst peeling off from substrate and related severe performance degradation. In this work, an in situ integration strategy of monolithic Au/TiO2 catalysts on Ti mesh for efficient and stable low‐temperature CO oxidation is reported. Plasma electrolytic oxidation technology can create a porous TiO2 seeding layer with strong substrate adherence. Subsequent hydrothermal reaction, ion exchange, and calcination processes can induce the in situ nucleation of sodium titanate nanosheets and their follow‐up conversion to TiO2 nanosheets with huge surface area. The oxygen defects generated in anatase TiO2 nanosheet supports can not only provide sufficient anchoring sites for the deposition and attachment of gold nanoparticles (Au NPs) during deposition–precipitation process, but also absorb and activate oxygen species. Meanwhile, the strong interactions between Au NPs and TiO2 support make the catalysts more chemically active. As a result, the Au/TiO2 monolithic catalysts can eliminate CO completely at low temperature and exhibit considerably high stability, suggesting their potential in practical applications. [ABSTRACT FROM AUTHOR]

Deoxygenation of fatty acids into liquid hydrocarbons is an efficient method of producing second-generation biofuels from biomass. Herein, we report efficient upgrading of stearic acid into a long-chain hydrocarbon at relatively low reaction temperature (140–220 °C) over a commercial Ru/C catalyst. The conversion process is predominantly through the hydrodecarboxylation pathway and not hydrodeoxygenation since heptadecane and not octadecane is found as the main product with the detection of CO2 in the gaseous products. The effects of process parameters including the solvent type (hexane, dodecane, isopropanol, water, and solvent-free), solvent volume, hydrogen pressure, catalyst loading, mass of feedstock, reaction temperature and reaction time on the conversion of stearic acid were systematically studied and optimized and the reusability of the catalyst was also studied. Hexane is found to be the most suitable solvent for the catalytic system. Under the optimized reaction conditions, 100% stearic acid conversion can be achieved at even 160 °C alongside a 90.1% yield of heptadecane. The apparent activation energy of the hydrodecarboxylation process over the commercial Ru/C catalyst was calculated to be 58.6 kJ mol−1. Notably, the reusability potential of the Ru/C catalyst is slightly limited by the accumulation of carbon deposits across multiple usage cycles. [ABSTRACT FROM AUTHOR]

Trichlorosilane (TCS), the primary chemical feedstock for production of high‐purity Si used in Si‐based solar cells, is currently manufactured industrially via a non‐catalytic hydrochlorination of metallurgical Si. This process generates a huge amount of undesirable silicon tetrachloride (STC) byproduct. Here we report the synthesis of yolk‐shell‐structured CuO−ZnO−In2O3 trimetallic oxide mesocrystal microspheres that can be employed as an efficient catalyst to produce TCS catalytically. The CuO−ZnO−In2O3 microspheres with multiple hetero‐interfaces were prepared using a facile solvothermal reaction followed by calcination. We found that differing from a single CuO mesocrystal, the electronic density on Cu atoms in the CuO phase within CuO−ZnO and CuO−ZnO−In2O3 can be tuned by varying the composition. When used as a catalyst for Si hydrochlorination reaction to produce TCS, CuO−ZnO−In2O3 shows excellent catalytic performance with very high Si conversion and TCS selectivity. Under the same reaction conditions, the TCS yield increased 13 times relative to the catalyst‐free process. This work demonstrates the possibility to decrease the amount of STC needed for the catalytic manufacture of TCS, and provides an approach to the facile synthesis of multi‐component mesocrystal materials with a specific structure. [ABSTRACT FROM AUTHOR]

Single-atom catalysts are of great interest because they can maximize the atom-utilization efficiency and generate unique catalytic properties; however, much attention has been paid to single-site active components, rarely to catalyst promoters. Promoters can significantly affect the activity and selectivity of a catalyst, even at their low concentrations in catalysts. In this work, we designed and synthesized CuO catalysts with atomically dispersed co-promoters of Sn and Zn. When used as the catalyst in the Rochow reaction for the synthesis of dimethyldichlorosilane, this catalyst exhibited much-enhanced activity, selectivity and stability compared with the conventional CuO catalysts with promoters in the form of nanoparticles. Density functional theory calculations demonstrate that single-atomic Sn substitution in the CuO surface can enrich surface Cu vacancies and promote dispersion of Zn to its atomic levels. Sn and Zn single sites as the co-promoters cooperatively generate electronic interaction with the CuO support, which further facilitates the adsorption of the reactant molecules on the surface, thereby leading to the superior catalytic performance. [ABSTRACT FROM AUTHOR]

2,5‐furandicarboxylic acid (2,5‐FDCA) produced from 5‐hydroxymethylfurfural (5‐HMF) is a promising renewable alternative to terephthalic acid. In this work, we prepared a Cu−Ni bimetallic catalyst with a CuNi(OH)2 structure by incipient wetness impregnation. This catalyst gave a 9.2 mA cm−2 current density for 5‐HMF oxidation at 1.45 V vs RHE. Finally, 100 % conversion of HMF with 93.3 % yield of 2,5‐FDCA was obtained. [ABSTRACT FROM AUTHOR]

A simple one‐pot method has been developed to synthesize a palladium/cuprous oxide‐copper (Pd/Cu2O–Cu) material with a well‐defined structure, by modification of Cu2O–Cu with Pd through a galvanic replacement reaction. Compared with the well‐known copper/cuprous oxide (Cu/Cu2O) catalysts, the Pd/Cu2O–Cu material can catalyze the electroreduction of CO2 into C1 products with much higher faradaic efficiencies at lower overpotentials in a CO2‐saturated 0.5 m NaHCO3 solution. In particular, the highest faradaic efficiencies of 92 % for formate and 30 % for methane were achieved at −0.25 and −0.65 V (vs. the reversible hydrogen electrode), respectively. The improvement is suggested to be the result of a synergistic effect between PdH and the catalytically active copper sites during electrochemical CO2 reduction. [ABSTRACT FROM AUTHOR]