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The Chang'e-5 mission returned new lunar samples after the last sample mission of the Moon 44 years ago, and is also the first mission that China has completed the sampling of extraterrestrial bodies. Recently, independent teams from the Institute of Geology, Chinese Academy of Geological Sciences, and the National Astronomical Observatories and the Institute of Geology and Geophysics, Chinese Academy of Sciences reported the first batch of results of Chang'e-5 lunar samples. The basic physical properties of the Chang'e-5 soil are within the range of the Apollo and Luna samples though the Chang'e-5 soil is finer-grained, better sorted, and has a slightly lower true density than the mare basalt previosuly reported. The Pb-Pb dating of U-rich minerals in the Chang'e-5 basalt clasts indicated that they formed at about 2.0 Ga, 800 million years younger than the youngest lunar sample recovered previously (2.8 Ga), confirming that lunar volcanic activity can last at least until 2 Ga. In-situ Sr-Nd isotope analyses suggested that the Chang'e-5 basalt originated from a depleted mantle source. The contribution of the KREEP component is less than 5%, which excluded the hypothesis that KREEP-rich sources provide an additional heat source for mantle melting. In addition, water contents and H isotopes of apatite and melt inclusions of the Chang'e-5 basalt suggested that the source region is not rich in water which can lower the melting point. Therefore, the reason why lunar volcanic activity can last so long is still unclear, which is a new direction for future lunar exploration and research. [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]

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]

An effective distribution of CNT within the HA can significantly improve the reinforcing efficiency. This paper describes a pulsed electrodeposition aided injection chemical vapor deposition (ICVD) for the preparation of a carbon nanotube (CNT) reinforced hydroxyapatite (HA) composite coating. The process involved the pulsed electrodeposition of HA and Fe catalyst, followed by the in situ ICVD synthesis of CNT. The CNT formed uniform distribution within the resulting CNT reinforced HA (CNT/HA) composite coating and bonded tightly with the HA. The CNT/HA composite coating exhibited a 1.73 times higher shear bonding strength than that of the pure HA coating. Simulated body fluid (SBF) experiment results have shown that the CNT/HA composite coating induced bone-like apatite and confirmed the bioactivity of the coating. Further electro-polarization tests have shown that the catalyst Fe reduced the equilibrium potential of the CNT/HA composite coating in the SBF solution, compared with the pure HA coating. [ABSTRACT FROM AUTHOR]

Abstract: Developing an efficient single‐atom material (SAM) synthesis and exploring the energy‐related catalytic reaction are important but still challenging. A polymerization–pyrolysis–evaporation (PPE) strategy was developed to synthesize N‐doped porous carbon (NPC) with anchored atomically dispersed Fe‐N4 catalytic sites. This material was derived from predesigned bimetallic Zn/Fe polyphthalocyanine. Experiments and calculations demonstrate the formed Fe‐N4 site exhibits superior trifunctional electrocatalytic performance for oxygen reduction, oxygen evolution, and hydrogen evolution reactions. In overall water splitting and rechargeable Zn–air battery devices containing the Fe‐N4 SAs/NPC catalyst, it exhibits high efficiency and extraordinary stability. This current PPE method is a general strategy for preparing M SAs/NPC (M=Co, Ni, Mn), bringing new perspectives for designing various SAMs for catalytic application. [ABSTRACT FROM AUTHOR]

Abstract: Developing an efficient single‐atom material (SAM) synthesis and exploring the energy‐related catalytic reaction are important but still challenging. A polymerization–pyrolysis–evaporation (PPE) strategy was developed to synthesize N‐doped porous carbon (NPC) with anchored atomically dispersed Fe‐N4 catalytic sites. This material was derived from predesigned bimetallic Zn/Fe polyphthalocyanine. Experiments and calculations demonstrate the formed Fe‐N4 site exhibits superior trifunctional electrocatalytic performance for oxygen reduction, oxygen evolution, and hydrogen evolution reactions. In overall water splitting and rechargeable Zn–air battery devices containing the Fe‐N4 SAs/NPC catalyst, it exhibits high efficiency and extraordinary stability. This current PPE method is a general strategy for preparing M SAs/NPC (M=Co, Ni, Mn), bringing new perspectives for designing various SAMs for catalytic application. [ABSTRACT FROM AUTHOR]

Surface modification is to modify biological responses through changing surface properties without reducing the mechanical properties of the implant. Specifically bioactive coatings, such as hydroxyapatite, carbonate apatite and dicalcium phosphate dehydrate, have been deposited on carbon/carbon (C/C) composites to change the bio-inert surface state. This work focused on the effects of voltages and electrolyte concentrations of pulsed electrodeposition on apatite layer. The apatite coatings thus synthesized were then structurally, morphologically and chemically characterized using X-ray diffraction, scanning electron microscopy, Transmission electron microscopy and Fourier-transform infrared spectroscopy. Remarkably, the voltages and electrolyte concentrations changed the structure, morphology and crystallinity of the obtained coatings. In vitro bioactivity evaluation of polymorphic apatite coatings was performed by soaking the apatite layer coated C/C composites in simulated body fluid (SBF). The corrosion behavior was investigated via the potentiodynamic polarization test in SBF solution. The results confirmed that the increasing deposition voltage and concentration of electrolyte resulted in promoting bioactivity and corrosion resistance by altering the morphologies and phases. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) possess excellent mechanical properties for their role playing in reinforcement as imparting strength to brittle hydroxyapatite (HA) bioceramic coating. However, there are few reports relating to the in-situ grown carbon nanotubes reinforced hydroxyapatite (CNTs-HA) coating. Here we demonstrate the potential application in reinforcing biomaterials by an attempt to use in-situ grown of CNTs strengthen HA coating, using a combined method composited of injection chemical vapor deposition (ICVD) and pulsed electrodeposition. The microstructure, phases and chemical compositions of CNTs-HA coatings were characterized by various advanced methods. The scanning electron microscopy (SEM) images indicated that CNTs-HA coatings avoided the inhomogeneous dispersion of CNTs inside HA coating. The result show that the interfacial shear strength between CNTs-HA coating and the C/C composite matrix reaches to 12.86 ± 1.43 MPa. Potenitodynamic polarization and electrochemical impedance spectroscopy (EIS) studies show that the content of CNTs affects the corrosion resistance of CNTs-HA coating. Cell culturing and simulated body fluid test elicit the biocompatibility with living cells and bioactivity of CNTs-HA coatings, respectively. [ABSTRACT FROM AUTHOR]

Carbon nanotubes-hydroxyapatite (CNTs-HA) composite coatings, which behaved like single composites, were synthesized by a combined method composed of electrophoretic deposition and pulsed electrodeposition. The phase compositions and the microstructure of the composite coatings were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectrometry (FTIR). Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) studies showed that the CNTs-HA composite coatings protected the bare carbon/carbon composites from corrosion in simulated body fluid (SBF) solution. The adhesion strength of CNTs-HA composite coating prepared by the combined method is 14.57±1.06 MPa achieved at the CNTs EPD time of 10 min. Compared to the other CNTs-HA composite coatings with different content of CNTs, the CNT-HA composite coating with the electrophoretic deposition of 10 min showed the best corrosion resistance. The morphology of CNTs-HA composite coatings immersed in SBF solution rendered the formation of HA crystallites. In addition, in vitro cellular responses to the CNTs-HA composite coatings were assessed to investigate the proliferation and morphology of mouse cells 3T3 cell line. [ABSTRACT FROM AUTHOR]

The rational design and construction of efficient and inexpensive bifunctional oxygen electrocatalysts are highly desirable for the development of rechargeable Zn–air batteries (ZABs). Although single‐atom Fe sites anchored on N‐doped carbon catalysts (Fe1/NC) ensure high oxygen reduction reaction activity, their unitary atomically dispersed active center faces difficult condition in catalyzing oxygen evolution reaction simultaneously. Herein, a composite catalyst containing heterointerface between Fe1/NC and selenides ((Fe,Co)Se2) is constructed. The obtained (Fe,Co)Se2@Fe1/NC exhibits extremely narrow potential gap of 0.616 V and remarkable stability in alkaline media, outperforming the benchmark catalysts (Pt/C+RuO2: 0.720 V). Experimental results and density functional theory calculations reveal that heterointerface between Fe1/NC and (Fe,Co)Se2 accelerates the electron transfer and provides more moderate adsorption sites, which endow (Fe,Co)Se2@Fe1/NC with extremely high bifunctional oxygen catalytic activity. This study not only provides a superior bifunctional catalyst for ZABs, but also enriches the application of single‐atom catalysts in multifunctional energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two new paragneisses containing detrital zircons as old as 3.8Ga were reported. [•] Multi-phased crustal addition and recycling from 3.8 to 3.4Ga were identified. [•] A nearly complete Archean crustal evolution was recorded in eastern Hebei. [Copyright &y& Elsevier]

A surface-enhanced Raman scattering (SERS) substrate based on porous carbon film supported Au nanoparticles (NPs) has been successfully fabricated by using an eggshell membrane as template. The as-prepared substrate exhibited excellent sensitivity toward Rhodamine 6G (R6G) at a low concentration of 1 × 10−9 M and great reproducibility with a small relative standard deviation (RSD) (16.3%) in the intensity of the main Raman peaks of the R6G. The good SERS signals could be due to the strong electromagnetic field coupling induced by the densely assembled Au NPs and the absence of surfactant. The high reproducibility and sensitivity in SERS was also found in the detection of Sudan dye at a low concentration of 1 × 10−8 M with a RSD of less than 20%. The results not only provide a facile and green approach to an ultrasensitive SERS substrate but also represented a new strategy to utilize daily consumption waste and turned them into useful materials for inspection of the environment pollutants and food safety. [ABSTRACT FROM AUTHOR]

The Daqingshan area in the North China Craton (NCC) incorporates several suites of magmatic intrusives including gabbros, granodiorites, charnockites and syenogranites, which were overprinted by subsequent metamorphic events. In this study, we report detailed morphological and textural characteristics as well as sensitive high resolution ion microprobe (SHRIMP) U-Pb ages of zircons from ten representative samples of the magmatic suites including syenogranites, charnockites and granodiorites. The zircons in these rocks are characterized by typical magmatic crystallization features including elongate prismatic grains with angular to sub-angular faces which are overprinted by a variety of reworked textures indicating strong recrystallization. These structures are terminated by thin and variable metamorphic overgrowths. U-Pb analyses of the zircons reveal multiple tectono-thermal events including magmatic crystallization at 2.30-2.00, 1.96-1.94 and 1.85-1.82 Ga and metamorphic overprint at 1.97-1.94 and 1.87-1.82 Ga. The episodic magmatism and regional metamorphism recorded in our study show a complex sequence of tectonic processes during the early to late Palaeoproterozoic associated with the amalgamation of crustal blocks within the NCC, with the youngest episode of the syenogranites representing regional extension at the end of the final cratonization of the NCC. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The Inner Mongolia Suture Zone (IMSZ, incorporating the Khondalite Belt) forms part of an accretionary orogen developed during the Paleoproterozoic collision between the Yinshan Block and Ordos Blocks within the North China Craton (NCC). The granulites within the IMSZ are characterized by high-temperature (HT) to ultrahigh-temperature (UHT) metamorphism with diagnostic mineral assemblages for UHT conditions preserved in some localities such as Tuguiwula and Wuchuan. We report here a new locality in Heling''er, located within the southern domain of the IMSZ where spinel–garnet–sillimanite-bearing granulites record UHT metamorphic conditions. The prograde assemblages occurring as inclusions in porphyroblastic minerals in these rocks include sillimanite+quartz+spinel, whereas coarse grained garnet+sillimanite+quartz+spinel+cordierite+plagioclase+K-feldspar+magnetite+ilmenite represent the peak assemblages. The retrograde stage is marked by orthopyroxene and cordierite rims developed on garnet and spinel. Biotite marks the final hydration stage of the high-grade metamorphism. Spinel and quartz occur in direct contact, with the spinel showing low Zn, Cr, and Fe3+. Application of Ti-in-zircon and ternary feldspar geothermometers yields temperatures up to ~940°C for the peak stage. Mineral phase equilibria modeling based on the bulk chemistry and mineral assemblages shows that the peak assemblage of garnet+plagioclase+spinel+cordierite+sillimanite+quartz+ilmenite+magnetite was stabilized at 1030°C at 6.5–7.5kbar, thus we infer a 940–1030°C temperature range for peak metamorphism in these rocks. The newly discovered UHT rocks in Heling''er, dated as 1.92Ga, together with the two previously reported UHT localities at Tuguiwula and Wuchuan, suggest that the Paleoproterozoic UHT metamorphism occurred on a regional scale within the IMSZ, probably in association with the subduction–accretion–collision tectonics and the incorporation of the NCC within the Columbia supercontinent. [Copyright &y& Elsevier]

Single‐metal atomic sites and vacancies can accelerate the transfer of photogenerated electrons and enhance photocatalytic performance in photocatalysis. In this study, a series of nickel hydroxide nanoboards (Ni(OH)x NBs) with different loadings of single‐atomic Ru sites (w‐SA‐Ru/Ni(OH)x) were synthesized via a photoreduction strategy. In such catalysts, single‐atomic Ru sites are anchored to the vacancies surrounding the pits. Notably, the SA‐Ru/Ni(OH)x with 0.60 wt % Ru loading (0.60‐SA‐Ru/Ni(OH)x) exhibits the highest catalytic performance (27.6 mmol g−1 h−1) during the photocatalytic reduction of CO2 (CO2RR). Either superfluous (0.64 wt %, 18.9 mmol g−1 h−1; 3.35 wt %, 9.4 mmol−1 h−1) or scarce (0.06 wt %, 15.8 mmol g−1 h−1; 0.29 wt %, 21.95 mmol g−1 h−1; 0.58 wt %, 23.4 mmol g−1 h−1) of Ru sites have negative effect on its catalytic properties. Density functional theory (DFT) calculations combined with experimental results revealed that CO2 can be adsorbed in the pits; single‐atomic Ru sites can help with the conversion of as‐adsorbed CO2 and lower the energy of *COOH formation accelerating the reaction; the excessive single‐atomic Ru sites occupy vacancies that retard the completion of CO2RR. [ABSTRACT FROM AUTHOR]

Single‐metal atomic sites and vacancies can accelerate the transfer of photogenerated electrons and enhance photocatalytic performance in photocatalysis. In this study, a series of nickel hydroxide nanoboards (Ni(OH)x NBs) with different loadings of single‐atomic Ru sites (w‐SA‐Ru/Ni(OH)x) were synthesized via a photoreduction strategy. In such catalysts, single‐atomic Ru sites are anchored to the vacancies surrounding the pits. Notably, the SA‐Ru/Ni(OH)x with 0.60 wt % Ru loading (0.60‐SA‐Ru/Ni(OH)x) exhibits the highest catalytic performance (27.6 mmol g−1 h−1) during the photocatalytic reduction of CO2 (CO2RR). Either superfluous (0.64 wt %, 18.9 mmol g−1 h−1; 3.35 wt %, 9.4 mmol−1 h−1) or scarce (0.06 wt %, 15.8 mmol g−1 h−1; 0.29 wt %, 21.95 mmol g−1 h−1; 0.58 wt %, 23.4 mmol g−1 h−1) of Ru sites have negative effect on its catalytic properties. Density functional theory (DFT) calculations combined with experimental results revealed that CO2 can be adsorbed in the pits; single‐atomic Ru sites can help with the conversion of as‐adsorbed CO2 and lower the energy of *COOH formation accelerating the reaction; the excessive single‐atomic Ru sites occupy vacancies that retard the completion of CO2RR. [ABSTRACT FROM AUTHOR]

Room-temperature sodium–sulfur (RT Na–S) batteries have the drawbacks of the poor shuttle effect of soluble sodium polysulfides (NaPSs) as well as slow sulfur redox kinetics, which result in poor cycling stability and low capacity, seriously affecting their extensive application. Herein, defect engineering is applied to construct rich oxygen vacancies at the interface of a TiO2 anatase/rutile homojunction (OV-TRA) to enhance sulfur affinity and redox reaction kinetics. Combining structural characterizations with electrochemical analysis reveals that OV-TRA well alleviates the shuttle effect of NaPSs and precipitates the deposition and diffusion kinetics of Na2S. Consequently, S/OV-TRA provides excellent electrochemical performance with a reversible capacity of 870 mA h g−1 at 0.1 C after 100 cycles and a long-term cycling capability of 759 mA h g−1 at 1 C after 1000 cycles. This work provides an effective interfacial defect engineering strategy to promote the application of metal oxides in RT Na–S batteries. [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]

Mesoporous nitrogen-doped carbon-anchored single atom Zn was synthesized through etching of ZIF-8 with 1,10-phenanthroline and subsequent pyrolysis based on the Kirkendall effect. The abundant pores and increased surface area promote CO2 adsorption and mass transfer, thus significantly improving the catalytic activity in solvent-free cycloaddition of epoxides with CO2. [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]

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]

Electroreduction of CO2 to liquid fuels such as ethanol and n‐propanol, powered by renewable electricity, offers a promising strategy for controlling the global carbon balance and addressing the need for the storage of intermittent renewable energy. In this work, we discovered that the composite composed of nitrogen‐doped graphene quantum dots (NGQ) on CuO‐derived Cu nanorods (NGQ/Cu‐nr) was an outstanding electrocatalyst for the reduction of CO2 to ethanol and n‐propanol. The Faradaic efficiency (FE) of C2+ alcohols could reach 52.4 % with a total current density of 282.1 mA cm−2. This is the highest FE for C2+ alcohols with a commercial current density to date. Control experiments and DFT studies show that the NGQ/Cu‐nr could provide dual catalytic active sites and could stabilize the CH2CHO intermediate to enhance the FE of alcohols significantly through further carbon protonation. The NGQ and Cu‐nr had excellent synergistic effects for accelerating the reduction of CO2 to alcohols. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 to liquid fuels such as ethanol and n‐propanol, powered by renewable electricity, offers a promising strategy for controlling the global carbon balance and addressing the need for the storage of intermittent renewable energy. In this work, we discovered that the composite composed of nitrogen‐doped graphene quantum dots (NGQ) on CuO‐derived Cu nanorods (NGQ/Cu‐nr) was an outstanding electrocatalyst for the reduction of CO2 to ethanol and n‐propanol. The Faradaic efficiency (FE) of C2+ alcohols could reach 52.4 % with a total current density of 282.1 mA cm−2. This is the highest FE for C2+ alcohols with a commercial current density to date. Control experiments and DFT studies show that the NGQ/Cu‐nr could provide dual catalytic active sites and could stabilize the CH2CHO intermediate to enhance the FE of alcohols significantly through further carbon protonation. The NGQ and Cu‐nr had excellent synergistic effects for accelerating the reduction of CO2 to alcohols. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 into energy‐dense chemical feedstock and fuels provides an attractive pathway to sustainable energy storage and artificial carbon cycle. Herein, we report the first work to use atomic Ir electrocatalyst for CO2 reduction. By using α‐Co(OH)2 as the support, the faradaic efficiency of CO could reach 97.6 % with a turnover frequency (TOF) of 38290 h−1 in aqueous electrolyte, which is the highest TOF up to date. The electrochemical active area is 23.4‐times higher than Ir nanoparticles (2 nm), which is highly conductive and favors electron transfer from CO2 to its radical anion (CO2.−). Moreover, the more efficient stabilization of CO2.− intermediate and easy charge transfer makes the atomic Ir electrocatalyst facilitate CO production. Hence, α‐Co(OH)2‐supported atomic Ir electrocatalysts show enhanced CO2 activity and stability. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 into energy‐dense chemical feedstock and fuels provides an attractive pathway to sustainable energy storage and artificial carbon cycle. Herein, we report the first work to use atomic Ir electrocatalyst for CO2 reduction. By using α‐Co(OH)2 as the support, the faradaic efficiency of CO could reach 97.6 % with a turnover frequency (TOF) of 38290 h−1 in aqueous electrolyte, which is the highest TOF up to date. The electrochemical active area is 23.4‐times higher than Ir nanoparticles (2 nm), which is highly conductive and favors electron transfer from CO2 to its radical anion (CO2.−). Moreover, the more efficient stabilization of CO2.− intermediate and easy charge transfer makes the atomic Ir electrocatalyst facilitate CO production. Hence, α‐Co(OH)2‐supported atomic Ir electrocatalysts show enhanced CO2 activity and stability. High‐density atomic Ir supported on α‐Co(OH)2 had outstanding performance for CO2 reduction to CO. The faradaic efficiency can reach 97.6 % with a TOF of 38 290 h−1. The high catalytic activity is attributed to more active sites for CO2 adsorption and activation and the higher efficiency in stabilizing the CO2.− intermediate. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The Erdaowa sequence was deposited at roughly the same time as the protoliths of the nearby khondalites. • O and Hf isotopic compositions of zircons suggest a high maturity of the metasedimentary rocks. • Rocks of same or similar age but with different metamorphic grades occur in the Khondalite Belt. • Tectonic slices were brought up to the same crustal level during the late Paleoproterozoic event. Abstract The Khondalite Belt is located in the northwestern North China Craton and contains late Paleoproterozoic metasedimentary rocks that generally underwent high-grade metamorphism. Only a few supracrustal sequences experienced low-grade metamorphism such as the Meidaizhao sequence in the Daqingshan area. The Erdaowa sequence north of Hohhot City, Inner Mongolia, is another late Paleoproterozoic supracrustal unit showing relatively low-grade metamorphism compared with the adjacent metapelitic khondalites. It is composed of metavolcanic as well as clastic metasedimentary rocks and marble. It was traditionally subdivided into the Halaqin and Hongshangou Formations. We undertook an integrated study of U-Pb zircon dating and O-Hf isotopic analysis, combined with whole-rock chemistry, on metasedimentary rocks of the Erdaowa sequence in order to understand the relationship between the low- and high-grade rocks and their tectono-thermal history in the Khondalite Belt. Cores and metamorphic domains of detrital zircons from a two-mica schist of the Halaqin Formation have 207Pb/206Pb ages of 2.0 and 1.86 Ga, δ18O values of 6.69–9.45‰ and 6.68–12.15‰, and ɛ Hf (t) values of +7.7 to +16.2 and +3.3 to +20.9, respectively. A recrystallized core, fir-tree domain and altered domain of zircon from a Grt-St-Ky two-mica gneiss have 207Pb/206Pb ages of >2.0 Ga, 1.88 Ga and 1.86 Ga, δ18O values of 12.10–12.75‰, 11.57–12.65‰ and 11.57–12.27‰, and ɛ Hf (t) values of +0.7 to +5.4, −2.0 to +4.7 and −2.0 to +0.5, respectively. These data limit the time of deposition of the sedimentary rocks between 2.0 and 1.88 Ga and show a high maturity, similar to khondalites of the same sequence. Compared with previous studies, we infer that the Erdaowa sequence consists of rocks of different origins and metamorphic grades (including khondalites), which were brought up to the same crustal level as tectonic slices due to late Paleoproterozoic tectonic processes. [ABSTRACT FROM AUTHOR]

Constructing electrocatalysts with p‐block elements is generally considered rather challenging owing to their closed d shells. Here for the first time, we present a p‐block‐element bismuth‐based (Bi‐based) catalyst with the co‐existence of single‐atomic Bi sites coordinated with oxygen (O) and sulfur (S) atoms and Bi nanoclusters (Biclu) (collectively denoted as BiOSSA/Biclu) for the highly selective oxygen reduction reaction (ORR) into hydrogen peroxide (H2O2). As a result, BiOSSA/Biclu gives a high H2O2 selectivity of 95 % in rotating ring‐disk electrode, and a large current density of 36 mA cm−2 at 0.15 V vs. RHE, a considerable H2O2 yield of 11.5 mg cm−2 h−1 with high H2O2 Faraday efficiency of ∼90 % at 0.3 V vs. RHE and a long‐term durability of ∼22 h in H‐cell test. Interestingly, the experimental data on site poisoning and theoretical calculations both revealed that, for BiOSSA/Biclu, the catalytic active sites are on the Bi clusters, which are further activated by the atomically dispersed Bi coordinated with O and S atoms. This work demonstrates a new synergistic tandem strategy for advanced p‐block‐element Bi catalysts featuring atomic‐level catalytic sites, and the great potential of rational material design for constructing highly active electrocatalysts based on p‐block metals. [ABSTRACT FROM AUTHOR]

Constructing electrocatalysts with p‐block elements is generally considered rather challenging owing to their closed d shells. Here for the first time, we present a p‐block‐element bismuth‐based (Bi‐based) catalyst with the co‐existence of single‐atomic Bi sites coordinated with oxygen (O) and sulfur (S) atoms and Bi nanoclusters (Biclu) (collectively denoted as BiOSSA/Biclu) for the highly selective oxygen reduction reaction (ORR) into hydrogen peroxide (H2O2). As a result, BiOSSA/Biclu gives a high H2O2 selectivity of 95 % in rotating ring‐disk electrode, and a large current density of 36 mA cm−2 at 0.15 V vs. RHE, a considerable H2O2 yield of 11.5 mg cm−2 h−1 with high H2O2 Faraday efficiency of ~90 % at 0.3 V vs. RHE and a long‐term durability of ~22 h in H‐cell test. Interestingly, the experimental data on site poisoning and theoretical calculations both revealed that, for BiOSSA/Biclu, the catalytic active sites are on the Bi clusters, which are further activated by the atomically dispersed Bi coordinated with O and S atoms. This work demonstrates a new synergistic tandem strategy for advanced p‐block‐element Bi catalysts featuring atomic‐level catalytic sites, and the great potential of rational material design for constructing highly active electrocatalysts based on p‐block metals. [ABSTRACT FROM AUTHOR]

Abundant mafic‐ultramafic blocks and dikes occur in the area north of Zunhua City, eastern Hebei Province, and were previously suggested to be part of a late Archean ophiolitic assemblage. We employed SHRIMP zircon dating and a geochemical study on these mafic and surrounding rocks to test the ophiolite hypothesis. The SHRIMP data suggest that three metagabbro samples were metamorphosed at ∼1.8 Ga. Numerous ∼2.5 Ga zircons display strong oscillatory zoning, characteristic of zircons from granitoid rocks but not from gabbro, so we suggest that these are xenocrystic grains. The age of these xenocrystic zircons and their metamorphic rims suggests that these mafic blocks formed in Paleoproterozoic. The surrounding gneiss of intermediate composition also contains 2.5 Ga zircons with oscillatory zoning and 1.8 Ga metamorphic rims. Fractionated REE patterns and Nb, Ta, Zr, Hf negative anomalies to variable extent were observed in the mafic blocks and surrounding rocks, also supporting a significant difference in the chemistry of ophiolitic rocks. Our data suggest that many mafic blocks in northern Zunhua are not part of a late Archean ophiolite complex but part of a tectonically dismembered Paleoproterozoic intrusive gabbro complex. This study shows that late Paleoproterozoic metamorphism occurred in the western part of eastern Hebei Province. [ABSTRACT FROM AUTHOR]

Supported Cu single-atom (Cu-SA) catalysts have exhibited unique activity and selectivity in CO 2 reduction, but they generally suffer from the easy transformation of active Cuδ+ into inactive Cu0. Herein, porous TiO 2 supported Cu single atoms (Cu-SAs/TiO 2) photocatalyst was fabricated and dioxygen (O 2) enhanced photocatalytic CO 2 reduction performance of Cu-SAs/TiO 2 was investigated by in-situ characterizations and theoretical calculations. The results showed that both activity and stability of Cu-SAs/TiO 2 photocatalyst could be improved by feeding a small amount of O 2 (117.6 ppm) in the reaction system. The competitive electron transfer to O 2 on Cu-SAs/TiO 2 maintained dynamic stability of Cuδ+ active sites, and O 2 -derived *OOH species lowered the formation energy barrier of key intermediate *COOH as well as delivered *H species for accelerating intermediates protonation process. Total yield rate of CH 4 and CO reached 34.64 μmol·g cat ·h−1 for CO 2 photoreduction over Cu-SAs/TiO 2 after introducing 117.6 ppm O 2 , accompanied by enhanced durability. [Display omitted] • Porous TiO 2 supported Cu single atoms (Cu-SAs/TiO 2) photocatalyst was fabricated. • Cu single-atom sites can significantly improve CO 2 photoreduction performance. • The dynamic stability of Cuδ+ sites is sustained by O 2 for photocatalytic CO 2 reduction. • The roles of O 2 are unraveled by in-situ characterizations and DFT calculations. [ABSTRACT FROM AUTHOR]

In photosynthesis, solar energy is harvested by photosensitizers, and then, the excited electrons transfer via a Z‐Scheme mode to enzymatic catalytic centers to trigger redox reactions. Herein, we constructed a core–shell Z‐scheme heterojunction of semiconductor@single‐atom catalysts (SACs). The oxygen‐vacancy‐rich ZnO core and single‐atom Co−N4 sites supported on nitrogen‐rich carbon shell (SA‐Co‐CN) act as the photosensitizer and the enzyme‐mimicking active centers, respectively. Driven by built‐in electric field across the heterojunction, photoexcited electrons could rapidly (2 ps) transfer from the n‐type ZnO core to the p‐type SA‐Co‐CN shell, finally boosting the catalytic performance of the surface‐exposed single‐atom Co−N4 sites for peroxymonosulfate (PMS) activation under light irradiation. The synergies between photocatalysis and heterogeneous Fenton‐like reaction lead to phenomenally enhanced production of various reactive oxygen species for rapid degradation of various microcontaminants in water. Experimental and theoretical results validate that the interfacial coupling of SA‐Co‐CN with ZnO greatly facilitates PMS adsorption and activation by reducing the adsorption energy and enhancing the cascade electron transfer processes for the photo‐Fenton‐like reaction. [ABSTRACT FROM AUTHOR]

In photosynthesis, solar energy is harvested by photosensitizers, and then, the excited electrons transfer via a Z‐Scheme mode to enzymatic catalytic centers to trigger redox reactions. Herein, we constructed a core–shell Z‐scheme heterojunction of semiconductor@single‐atom catalysts (SACs). The oxygen‐vacancy‐rich ZnO core and single‐atom Co−N4 sites supported on nitrogen‐rich carbon shell (SA‐Co‐CN) act as the photosensitizer and the enzyme‐mimicking active centers, respectively. Driven by built‐in electric field across the heterojunction, photoexcited electrons could rapidly (2 ps) transfer from the n‐type ZnO core to the p‐type SA‐Co‐CN shell, finally boosting the catalytic performance of the surface‐exposed single‐atom Co−N4 sites for peroxymonosulfate (PMS) activation under light irradiation. The synergies between photocatalysis and heterogeneous Fenton‐like reaction lead to phenomenally enhanced production of various reactive oxygen species for rapid degradation of various microcontaminants in water. Experimental and theoretical results validate that the interfacial coupling of SA‐Co‐CN with ZnO greatly facilitates PMS adsorption and activation by reducing the adsorption energy and enhancing the cascade electron transfer processes for the photo‐Fenton‐like reaction. [ABSTRACT FROM AUTHOR]

A dual-layer coating composed of in situ grown Si 3 N 4 microbelt (SNM) and Mg doped hydroxyapatite (MH) for carbon/carbon composites has been synthesized using a combination method of precursor pyrolysis and electrochemical deposition method. The morphology, microstructure, in vitro bioactivity, bonding strength and corrosion resistance of the coating are analyzed. The results show that SNM exhibits a belt shape and MH shows a flake shape. SNM/MH coating exhibits good bioactivity and suitable bonding strength. SNM/MH dual-layer coating exhibits better corrosion resistance than MH single layer coating. SNM/MH is expected to have potential medical application as coating materials in hard tissue substitution application. [ABSTRACT FROM AUTHOR]

Due to the surface inhomogeneity of the solid supports, direct growth of uniform bimetallic nanoparticles (NPs) with controllable structure and size thereon is particularly challenging. Herein, a surface‐confinement strategy is reported to directly prepare ultrafine bimetallic PtM NPs (MFe, Cu, and Co) with structure of core‐shell or intermetallic compounds on an N functionalized carbon support (NC). It is found that the N species of NC support can atomically disperse metal cations of precursors, which largely renders uniform nucleation and growth of bimetallic NPs and fine structure modulation of them. In another regard, metal transfer is confined to a narrow region on NC via N‐mediation, hence greatly favoring localized particle growth and formation of ultrafine bimetallic NPs. Remarkably, the ultrafine 3.1 ± 0.7 nm intermetallic Pt3Fe NPs on NC displayed excellent catalytic activity and durability toward electrochemical hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

The accretion and recycling of Archean-Paleoproterozoic continental crust is the key to understanding the formation and evolution of early continental crust. Early Precambrian metamorphic basement is well developed in the Aktashtagh area, southeastern margin of the Tarim Craton, northwestern China. We report zircon SHRIMP U Pb dating, LA-MC-ICP-MS Lu Hf isotopic analysis and whole-rock geochemical analysis on 16 samples (mainly TTG, tonalite-trondhjemite-granodiorite) from Aktashtagh. Multiple episodes of early Precambrain magmatism, including 3.72 Ga, 3.63 Ga, 3.10 Ga, 2.83–2.69 Ga, 2.55–2.50 Ga, 2.05–2.02 Ga and 1.93–1.82 Ga events, have been identified in the Aktashtagh region. The most intense magmatism occurred in the late Mesoarchean to early Neoarchean. Significantly, 3.63 Ga and 3.10 Ga TTG rocks are identified, together with more extensive 2.8–2.7 Ga and ∼ 2.5 Ga TTG rocks. The TTG suites are dominated by tonalitic, with some trondhjemitic and grandioritic rocks. They show large variations in REE contents, are mainly distributed in the high- and medium-pressure fields in the Sr/Y-Y and La/Yb-Yb diagrams, and the 2.7 Ga TTG rocks commonly show higher and more variable Sr/Y and La/Yb ratios. The 3.63–3.10 Ga TTG rocks have magmatic zircon ε Hf (t) values of −3.9 to +3.1 and t DM1 (Hf) model ages of 3.9–3.6 Ga, whereas the ∼2.7–2.51 Ga TTG rocks have magmatic zircon ε Hf (t) values of −13.4 to +2.1 and t DM1 (Hf) model ages of 3.3–3.0 Ga. The ∼2.7 to ∼2.0 Ga meta-gabbroic-dioritic rocks have magmatic zircon ε Hf (t) values of −19.7 to +0.6 and t DM1 (Hf) model ages of 3.2–2.4 Ga. Metamorphic zircon ages of 3.56 Ga, 2.75–2.73 Ga, 2.53–2.51 Ga, 2.03–1.96 Ga and ∼ 1.85 Ga are also recorded, whereas ∼2.83 Ga, 2.53–2.40 Ga, 2.05–2.02 Ga and 1.86–1.83 Ga crustally-derived K-rich granites are identified, with the most important occurring in the late Neoarchean and late Paleoproterozoic. In this regard, the Tarim Craton is similar to the North China Craton in its early Precambrian geological evolution. The main difference is that the Paleoproterozoic tectonothermal event in the Tarim Craton started as early as 2.00 Ga, whereas in the North China Craton it occurred between 1.95 and 1.80 Ga. • Aktashtagh of the southeastern Tarim Craton has multiple episodes of magmatism from 3.72 to 1.82 Ga. • TTG show large Sr/Y-Y and La/Yb-Yb variations and magmatic zircons have ε Hf (t) of −15.2 to +3.1. • There were multiple Paleoarchaean to Paleoproterozoic events leading to crustal recycling. • The early Precambrian geological records are similar to those in the North China Craton. • The Tarim and North China cratons may be different portions of a larger craton. [ABSTRACT FROM AUTHOR]

The two‐dimensional nanosheets are conducive to not only endow opened surfaces for loading active metal atoms but also boost the mass transfer for the heterogeneous reactions. The challenge is how to load and stabilize single‐atoms on nanosheets in high‐areal densities. This work reports an efficient micro‐gas blasting (MGB) strategy to access versatile noble metal single‐atoms/metal oxide nanosheets, including Ir1/CoOx, Pd1/CeO2, etc. Especially for Pt/CeO2 nanosheets (Pt1/CeO2−S), the Pt loading is increased to 15 at%. The Pt1/CeO2−S catalysts from MGB are revealed to possess superior reactivity and tolerance in the model reaction of water‐gas shift (WGS). The Pt1/CeO2−S catalyst exhibit 2–3 times reactivity that of their thicker counterpart, single‐atom Pt1/CeO2 microspheric catalyst. Moreover, the single‐atom sites in Pt1/CeO2−S (1–10 %) catalysts are stable in a harsh WGS reaction condition of 10 % CO. This work thus paves a way to access the practical single‐atom catalysts. [ABSTRACT FROM AUTHOR]

The two‐dimensional nanosheets are conducive to not only endow opened surfaces for loading active metal atoms but also boost the mass transfer for the heterogeneous reactions. The challenge is how to load and stabilize single‐atoms on nanosheets in high‐areal densities. This work reports an efficient micro‐gas blasting (MGB) strategy to access versatile noble metal single‐atoms/metal oxide nanosheets, including Ir1/CoOx, Pd1/CeO2, etc. Especially for Pt/CeO2 nanosheets (Pt1/CeO2−S), the Pt loading is increased to 15 at%. The Pt1/CeO2−S catalysts from MGB are revealed to possess superior reactivity and tolerance in the model reaction of water‐gas shift (WGS). The Pt1/CeO2−S catalyst exhibit 2–3 times reactivity that of their thicker counterpart, single‐atom Pt1/CeO2 microspheric catalyst. Moreover, the single‐atom sites in Pt1/CeO2−S (1–10 %) catalysts are stable in a harsh WGS reaction condition of 10 % CO. This work thus paves a way to access the practical single‐atom catalysts. [ABSTRACT FROM AUTHOR]

• Unexpected amorphization promoting effect was found for Ni nanocatalyst. • Superb DRM activity and coke-resistance were achieved over amorphous Ni catalyst. • The amorphization promoting effect was unveiled both by experiment and simulation. Selective conversion of CH 4 and CO 2 to syngas via the dry reforming reaction is highly desirable in terms of restraining the greenhouse effect and meanwhile acquiring useful chemicals. However, the most promising Ni catalysts for the reaction still suffer from severe coking and thus poor durability. Here, we report that using amorphous Ni nanoparticles synthesized on an N modified mesoporous silica support, the catalytic activity and coke-resistant performance of Ni toward the photothermal dry reforming of methane (DRM) are greatly improved. Theoretical calculations further unveil that the amorphous Ni nanoparticles are much more energetically favorable to activate the CH 4 and CO 2 molecules as well as to remove the C* intermediates for coke formation than their crystalline Ni counterparts, which renders the amorphous Ni nanoparticles with both superb activity and excellent coke-resisting property. This finding possibly provides a new avenue to make both highly efficient and anti-coking catalysts for the DRM reaction and beyond via facile amorphization of active metals. [ABSTRACT FROM AUTHOR]

It is extremely challenging to controllably synthesize rare earth‐containing nanoalloys due to the ultralow standard reduction potential of rare earth metals. Here, a surface‐confined strategy to prepare ultrafine Pt‐rare earth nanoalloys on a series of N‐functionalized supports is reported. It proves that by surface N‐metal coordination, the metal cations of precursors are atomically dispersed on support, which greatly favors uniform nucleation and growth of particles upon reduction. Moreover, the moderate metal transfer barrier from N ensures particle growth in a confined region to form ultrafine nanoalloys. Using this method, ultrafine PtLa, PtY, and PtDy nanoalloys are prepared on N‐functionalized supports such as carbon, zeolite, and Al2O3. Notably, the PtLa nanoalloys on N‐functionalized zeolite show superior activity and durability for propane oxidation. The strategy is expected to provide guidelines for preparing highly efficient rare earth‐containing nanoalloys for catalysis applications. [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]

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]

Herein, a novel strategy has been proposed to design a hollow structure via post-modified N sites coordinating to metal species. As a result, an atomically dispersed Co site catalyst with high loading has been obtained and has shown superb performance in CO2 cycloaddition to ethylene carbonate. This novel avenue can be extended to other atomically dispersed metal catalysts with high loading. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 into valuable fuels and feedstocks offers a promising way for CO2 utilization. However, the commercialization is limited by the low productivity. Here, we report a strategy to enhance the productivity of CO2 electroreduction by improving diffusion of CO2 to the surface of catalysts using porous organic cages (POCs) as an additive. It was noted that the Faradaic efficiency (FE) of C2+ products could reach 76.1 % with a current density of 1.7 A cm−2 when Cu‐nanorod(nr)/CC3 (one of the POCs) was used, which were much higher than that using Cu‐nr. Detailed studies demonstrated that the hydrophobic pores of CC3 can adsorb a large amount of CO2 for the reaction, and the diffusion of CO2 in the CC3 to the nanocatalyst surface is easier than that in the liquid electrolyte. Thus, more CO2 molecules make contact with the nanocatalysts in the presence of CC3, enhancing CO2 reduction and inhibiting generation of H2. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 into valuable fuels and feedstocks offers a promising way for CO2 utilization. However, the commercialization is limited by the low productivity. Here, we report a strategy to enhance the productivity of CO2 electroreduction by improving diffusion of CO2 to the surface of catalysts using porous organic cages (POCs) as an additive. It was noted that the Faradaic efficiency (FE) of C2+ products could reach 76.1 % with a current density of 1.7 A cm−2 when Cu‐nanorod(nr)/CC3 (one of the POCs) was used, which were much higher than that using Cu‐nr. Detailed studies demonstrated that the hydrophobic pores of CC3 can adsorb a large amount of CO2 for the reaction, and the diffusion of CO2 in the CC3 to the nanocatalyst surface is easier than that in the liquid electrolyte. Thus, more CO2 molecules make contact with the nanocatalysts in the presence of CC3, enhancing CO2 reduction and inhibiting generation of H2. [ABSTRACT FROM AUTHOR]

Two‒dimensional polymeric carbon nitride (2DPCN) is a versatile support for constructing single atom catalysts (SACs). Herein, we demonstrated a facile strategy for constructing atomic Co sites on 2DPCN. Atomic dispersion of Co was confirmed by the aberration‒corrected high angle annular dark field scanning transmission electron microscopy, while the extended X‒ray absorption fine structure spectroscopy analysis precisely corroborated the existence of atomic Co1–N 4 non square planar sites on 2DPCN support. Remarkably, Co1/2DPCN catalyst yielded H 2 at a rate of 28.3mmol H2 h−1 g Co −1, which is approximately 4.2 times higher than that of CoNPs/2DPCN (6.8mmol H2 h−1g Co −1) counterpart. Notably, with 0.75 wt % Pt as a co‒catalyst, H 2 evolution activity for Co1/2DPCN and CoNPs/2DPCN reached as high as 138.6 mmol H2 h−1 g metal −1 and 22.4mmol H2 h−1 g metal −1, respectively, which could be attributed to the synergistic effect of atomic Co1–N 4 sites and Pt. Both DFT calculations and spectroscopic results revealed that as constructed atomic Co1–N 4 sites, reduced band gap energy, improved light harvesting ability and decreased energy barrier for H 2 evolution. [Display omitted] • Demonstrated facile synthesis of Co single atoms on 2D polymeric carbon nitride support (Co1/2DPCN). • XAS analysis revealed the presence of distinct non square planar Co–N 4 atomic sites. • Atomic Co–N 4 sites promoted light absorption and directional charge transfer. • The atomic Co1/2DPCN catalyst achieved 28.3mmol H2 h−1 g Co −1 activity without the assistant of noble metal co‒catalyst. • Proposed H 2 evolution mechanism on the basis of experimental results and DFT calculations. [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]

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]

[Display omitted] • Bimetallic cobalt iron boride nanoparticle catalyst was successfully synthesized. • The bimetallic cobalt iron boride catalyst shows excellent over all water splitting performance. • Outstanding performance of the catalyst roots form the synergistic effect of the optimized electronic and composition. Developing an efficient bifunctional catalyst for Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) in water splitting technology is very attractive for clean energy. Here, a new Co-Fe-B ternary catalyst with improved crystallinity is successfully synthesized by combining the chemical reduction and subsequent solid-state reaction method. Synchrotron-based X-ray absorption near-edge structure (XANES) and X-ray photoelectron spectroscopy (XPS) indicate the electronic structure redistribution is favor for the improved performance. The overpotential is only 129 mV and 280 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline condition, the corresponding Tafel slope is 67.3 mV dec−1 and 38.9 mV dec−1. Density functional theory calculations distinguish that the ternary crystalline Co-Fe-B catalysts are thermodynamically favorable for HER and OER. The actual active species of the ternary catalyst in OER is the CoOOH and FeOOH as indicated in ex situ Raman spectra. The present work may introduce promising crystallinity borides material for the anode and cathode of water splitting device. [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]

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]