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Amorphous nano-metal catalysts often exhibit appealing catalytic properties, because the intrinsic linear scaling relationship can be broken. However, accurate control synthesis of amorphous nano-metal catalysts with desired size and morphology is a challenge. In this work, we discover that Cu(0) could be oxidized to amorphous CuxO species by supercritical CO2. The formation process of the amorphous CuxO is elucidated with the aid of machine learning. Based on this finding, a method to prepare Cu nanoparticles with an amorphous shell is proposed by supercritical CO2 treatment followed by electroreduction. The unique feature of this method is that the size of the particles with amorphous shell can be easily controlled because their size depends on that of the original crystal Cu nanoparticles. Moreover, the thickness of the amorphous shell can be easily controlled by CO2 pressure and/or treatment time. The obtained amorphous Cu shell exhibits high selectivity for C2+ products with the Faradaic efficiency of 84% and current density of 320 mA cm−2. Especially, the FE of C2+ oxygenates can reach up to 65.3 %, which is different obviously from the crystalline Cu catalysts. Amorphous metal catalysts often exhibit appealing catalytic properties, however, accurate control synthesis of amorphous nano-metal catalysts is a challenge. Here, the authors report a feasible strategy to prepare the amorphous Cu catalysts by supercritical CO2 treatment followed by electroreduction. The resulted catalyst shows high selectivity towards multi-carbon products for CO2 electroreduction. [ABSTRACT FROM AUTHOR]

Developing electrocatalytic reactions with high‐efficiency can make important contributions to carbon neutrality. However, poor long‐term stability of catalysts is a bottleneck for its practical application. Herein, an "in situ periodic regeneration of catalyst (PR‐C)" strategy is proposed to give long‐term high efficiency of CO2 electroreduction to generate C2+ products over Cu catalyst by applying a positive potential pulse for a short time periodically in the halide‐containing electrolyte. The high Faradaic efficiency (81.2 %) and current density (22.6 mA cm−2) could be maintained completely at least 36 h, while the activity and selectivity decreased continuously without using the PR‐C method. Control experiments and operando characterization demonstrated that the surface structure and oxidation state of Cu could be recovered periodically by the PR‐C method, which was beneficial for CO2 activation and C−C coupling. [ABSTRACT FROM AUTHOR]

Electrocatalytic reduction of CO2 (CO2RR) to value‐added chemicals is of great significance for CO2 utilization, however the CO2RR process involving multi‐electron and proton transfer is greatly limited by poor selectivity and low yield. Herein, We have developed an atomically dispersed monovalent zinc catalyst anchored on nitrogenated carbon nanosheets (Zn/NC NSs). Benefiting from the unique coordination environment and atomic dispersion, the Zn/NC NSs exhibit a superior CO2RR performance, featuring a high current density up to 50 mA cm−2 with an outstanding CO Faradaic efficiency of ≈95 %. The center ZnI atom coordinated with three N atoms and one N atom that bridges over two adjacent graphitic edges (Zn‐N3+1) is identified as the catalytically active site. Experimental results reveal that the twisted Zn‐N3+1 structure accelerates CO2 activation and protonation in the rate‐determining step of *CO2 to *COOH, while theoretical calculations elucidate that atomically dispersed Zn‐N3+1 moieties decrease the potential barriers for intermediate COOH* formation, promoting the proton‐coupled CO2RR kinetics and boosting the overall catalytic performance. [ABSTRACT FROM AUTHOR]

Using renewable electricity to drive CO2 electroreduction is an attractive way to achieve carbon‐neutral energy cycle and produce value‐added chemicals and fuels. As an important platform molecule and clean fuel, methanol requires 6‐electron transfer in the process of CO2 reduction. Currently, CO2 electroreduction to methanol suffers from poor efficiency and low selectivity. Herein, we report the first work to design atomically dispersed Sn site anchored on defective CuO catalysts for CO2 electroreduction to methanol. It exhibits high methanol Faradaic efficiency (FE) of 88.6 % with a current density of 67.0 mA cm−2 and remarkable stability in a H‐cell, which is the highest FE(methanol) with such high current density compared with the results reported to date. The atomic Sn site, adjacent oxygen vacancy and CuO support cooperate very well, leading to higher double‐layer capacitance, larger CO2 adsorption capacity and lower interfacial charge transfer resistance. Operando experiments and density functional theory calculations demonstrate that the catalyst is beneficial for CO2 activation via decreasing the energy barrier of *COOH dissociation to form *CO. The obtained key intermediate *CO is then bound to the Cu species for further reduction, leading to high selectivity toward methanol. [ABSTRACT FROM AUTHOR]

Guided by first‐principles calculations, it was found that Cd single‐atom catalysts (SACs) have excellent performance in activating CO2, and the introduction of axial coordination structure to Cd SACs cannot only further decrease the free energy barrier of CO2 reduction, but also suppress the hydrogen evolution reaction (HER). Based on the above discovery, we designed and synthesized a novel Cd SAC that comprises an optimized CdN4S1 moiety incorporated in a carbon matrix. It was shown that the catalyst exhibited outstanding performance in CO2 electroreduction to CO. The faradaic efficiency (FE) of CO could reach up to 99.7 % with a current density of 182.2 mA cm−2 in a H‐type electrolysis cell, and the turnover frequency (TOF) value could achieve 73000 h−1, which was much higher than that reported to date. This work shows a successful example of how to design highly efficient catalysts guided by theoretical calculations. [ABSTRACT FROM AUTHOR]

Effecting the synergistic function of single metal atom sites and their supports is of great importance to achieve high-performance catalysts. Herein, we successfully fabricate polyoxometalates (POMs)-stabilized atomically dispersed platinum sites by employing three-dimensional metal-organic frameworks (MOFs) as the finite spatial skeleton to govern the accessible quantity, spatial dispersion, and mobility of metal precursors around each POM unit. The isolated single platinum atoms (Pt1) are steadily anchored in the square-planar sites on the surface of monodispersed Keggin-type phosphomolybdic acid (PMo) in the cavities of various MOFs, including MIL-101, HKUST-1, and ZIF-67. In contrast, either the absence of POMs or MOFs yielded only platinum nanoparticles. Pt1-PMo@MIL-101 are seven times more active than the corresponding nanoparticles in the diboration of phenylacetylene, which can be attributed to the synergistic effect of the preconcentration of organic reaction substrates by porous MOFs skeleton and the decreased desorption energy of products on isolated Pt atom sites. It is of great significance to exert the synergistic effect between single atom and support. Here, the authors prepare polyoxometalates-stabilized single-atom site catalysts in confined space with enhanced activity for alkynes diboration. [ABSTRACT FROM AUTHOR]

A dual‐site catalyst allows for a synergetic reaction in the close proximity to enhance catalysis. It is highly desirable to create dual‐site interfaces in single‐atom system to maximize the effect. Herein, we report a cation‐deficient electrostatic anchorage route to fabricate an atomically dispersed platinum–titania catalyst (Pt1O1/Ti1−xO2), which shows greatly enhanced hydrogen evolution activity, surpassing that of the commercial Pt/C catalyst in mass by a factor of 53.2. Operando techniques and density functional calculations reveal that Pt1O1/Ti1−xO2 experiences a Pt−O dual‐site catalytic pathway, where the inherent charge transfer within the dual sites encourages the jointly coupling protons and plays the key role during the Volmer–Tafel process. There is almost no decay in the activity of Pt1O1/Ti1−xO2 over 300 000 cycles, meaning 30 times of enhancement in stability compared to the commercial Pt/C catalysts (10 000 cycles). [ABSTRACT FROM AUTHOR]

Herein, we designed and prepared a novel Fe/Fe2O3‐based catalyst, in which a remarkable synergistic effect has been revealed between Fe and Fe2O3 encapsulated in N‐doping porous carbon. The Fe‐based catalysts were fabricated via pyrolysis a mixture of MIL‐101(Fe) and melamine. The catalyst exhibits exceptionally high catalytic activity (TOFs up to 8898 h−1 which is about 100 times higher than the similar kinds of catalysts) and chemoselectivity for nitroarene reduction under mild conditions. Catalysis magic! Fe‐based NPs catalyst encapsulated in N‐doping porous carbon exhibits high catalytic active (with TOF=8898 h−1 which is about 100 of times higher than the similar catalysts) and chemoselectivity for nitro compounds reduction. [ABSTRACT FROM AUTHOR]

[Display omitted] Maximally exploiting the active sites of iridium catalysts is essential for building low-cost proton exchange membrane (PEM) electrolyzers for green H 2 production. Herein, we report a novel microdrop-confined fusion/blasting (MCFB) strategy for fabricating porous hollow IrO 1− x microspheres (IrO 1− x -PHM) by introducing explosive gas mediators from a NaNO 3 /glucose mixture. Moreover, the developed MCFB strategy is demonstrated to be general for synthesizing a series of Ir-based composites, including Ir–Cu, Ir–Ru, Ir–Pt, Ir–Rh, Ir–Pd, and Ir–Cu–Pd and other noble metals such as Rh, Ru, and Pt. The hollow structures can be regulated using different organics with NaNO 3. The assembled PEM electrolyzer with IrO 1− x -PHM as the anode catalyst (0.5 mg/cm2) displays an impressive polarization voltage of 1.593 and 1.726 V at current densities of 1 and 2 A/cm2, respectively, outperforming commercial IrO x catalysts and most of the ever-reported iridium catalysts with such low catalyst loading. More importantly, the breakdown of the polarization loss indicates that the improved performance is due to the facilitated mass transport induced by the hollowness. This study offers a versatile platform for fabricating efficient Ir-based catalysts for PEM electrolyzers and beyond. [ABSTRACT FROM AUTHOR]

• A strategy of Pd crystal transformation induced by in-situ doping P is proposed. • Electrocatalytic hydrodechlorination of amorphous Pd–P catalyst is studied. • Dechlorination performance of Pd-P catalyst is affected by coordination structure. • Doping P facilitates desorption of phenol and weakens toxic effect on active sites. • Crystal effect and coordination effect of Pd-based catalyst are discovered. Developing catalysts with high activity and high atom utilization as well as exploring catalytic active sites are the biggest challenges for the electrocatalytic hydrodechlorination technology. Herein, a novel strategy of Pd crystal transformation induced by in-situ doping was proposed, and a series of amorphous Pd–P nanoparticles (NPs) with controllable coordination environment were synthesized successfully. The amorphous Pd–P NPs catalyst exhibits the highest activity for electrocatalytic hydrodechlorination and good cycling stability when the Pd–P coordination number is 3 and the Pd–Pd coordination number is 4. The 4-chlorophenol hydrodechlorination efficiency of Pd–P-60 NPs reaches 100 % within 2 h, and the mass activity is 8.58 min−1 g−1, which is 5.57 times as high as that for crystalline Pd NPs catalyst. Theoretical calculation shows that Pd–P catalyst facilitates the desorption of phenol and weakens the toxic effect on active sites. Density of states indicate that the doping of P results in a downshift of d -band center, facilitating the desorption of phenol. This work discovers the crystal effect and coordination effect of amorphous Pd–P NPs for electrocatalytic hydrodechlorination, which lays an important theoretical foundation for the design and development of high-performance Pd-based catalysts for electrocatalytic hydrodechlorination. [ABSTRACT FROM AUTHOR]

• Graphitic carbon modified Mn 3 O 4 (Mn 3 O 4 @G-A) derived from MOFs is prepared. • Mn 3 O 4 @G-A is active to selective catalytic reduction of NO by NH 3 under high GHSV. • Mn 3 O 4 @G-A exhibits significantly improved SO 2 resistance in comparison to pure Mn 3 O 4. • The role of graphitic carbon in improving the SO 2 resistance of Mn 3 O 4 is discussed. The biggest challenge for selective catalytic reduction (SCR) of NO by NH 3 at low temperatures is to develop robust catalysts with high resistance to SO 2. Mn-based catalysts have attracted great attention for their excellent activity, but the poor SO 2 resistance limits their application. Herein, we report a novel assembled composite featuring Mn 3 O 4 nanoparticles embedded in defect-abundant graphitic carbon frame (Mn 3 O 4 @G-A) via a confinement–pyrolysis–oxidation strategy derived from MOF. The Mn 3 O 4 @G-A exhibits excellent activity (reaching over 90 % NO conversion in 100, 000 h−1 GHSV at 160 °C) and significantly improved SO 2 resistance in comparison to pristine Mn 3 O 4 , and all the performance tests were conducted with 5.6 vol.% water vapor. By combining synchrotron radiation-based X-ray absorption spectroscopy and density functional theory calculation, we further discovered the positive role and the origin of graphitic carbon for improving SO 2 resistance. Over the Mn 3 O 4 @G-A sample, the electrons can be transferred from graphitic carbon to Mn 3 O 4 nanoparticles, which can regulate the electronic properties and oxidizing ability of Mn 3 O 4 nanoparticles. The proper oxidizing ability of Mn 3 O 4 @G-A can inhibit the oxidation of SO 2 to SO 3 , thus further avoid the formation of NH 4 HSO 4 and improve the SO 2 resistance. Our work here not only solves the current problem of poor SO 2 resistance of Mn-based catalysts, but also provides new insights into the design and synthesis of MOF-derived graphitic carbon-containing catalysts for SCR applications. [ABSTRACT FROM AUTHOR]

A hard-magnet L 1 0 -ordered PtFe-alloy nanopillar film (L 1 0 -PtFe NF) is employed as a model catalyst to evaluate its magnetic effect on ORR performance. A magneto-enhancement in ORR catalysis is demonstrated for magnetized L 1 0 -PtFe(M) NF, compared with original L 1 0 -PtFe NF. The chemisorbed oxygen on catalyst surface, especially the primary Pt d yz –O 2 π* coupling, manipulated by the magnetic effect plays the key role in the catalysis optimization. • A fully L 1 0 -ordered PtFe nanopillar film was engineered as the model catalyst. • The magnetic effect within L 1 0 -PtFe substantially regulates the ORR performance. • The coverage of oxygen on Pt, substantially the primary Pt d yz –O 2 π* coupling, is manipulated by the magnetic effect. • It paves the way for the implementation of magnetic effect towards broad catalysis. It is important to improve the oxygen reduction reaction (ORR) performance of Pt by alloying it with first-row transition metals (M: e.g., Fe, Co, Ni). It is known that the ligand, strain, and ensemble effects govern the ORR performance. However, the intrinsic magnetic characteristics of PtMs have rarely been focused on in ORR investigations. Here, we employed a hard-magnet L 1 0 -ordered PtFe nanopillar film (L 1 0 -PtFe NF) as model catalyst to uncover the catalyst's magnetic effect on the ORR. We report a five-fold enhancement of the catalytic efficiency of magnetized L 1 0 -PtFe(M) NF compared with unmagnetized one. Further investigations demonstrate that the coverage of chemisorbed oxygen on catalyst surface, especially the primary Pt d yz –O 2 π* coupling, manipulated by the catalyst's magnetic field is the key factor for the ORR regulation. This work thus paves the way for the implementation of magnetic effect towards the precise regulation in broad catalysis applications. [ABSTRACT FROM AUTHOR]