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Small metal clusters with novel structures, which have interesting perporties and important potential applications, could be stabilized by substrate surfaces. In this work, by using density functional theory (DFT) calculations, we studied the geometric and electronic structures of Pdn (n=1‐5) clusters supported on the well‐studied (110) surface and (100) and (001) surfaces of rutile TiO2 together. It is found that the surface plays a vital role in stabilizing Pd cluster structure. The (110) surface influences slightly on the geometries of Pd clusters, where Pd cluster on the TiO2(100) surface prefers to grow as a linear mode. The Pdn cluster are obviously diffused by the (001) surface because of the strong interaction between Pd and TiO2 substrate where the adsorption energy ranges from −3.54 to −6.57 eV. Pd1/TiO2(001) is predicted to be stable because the nucleation from Pd1 to Pd2 on TiO2(001) is an endothermic process. All the Pdn clusters are positively charged while the 4d orbitals of Pd are predominant near the Fermi level. [ABSTRACT FROM AUTHOR]

Designing highly active material to fabricate high-performance glucose sensor was great importance for diabetes treatment. In this work, we develop a novel nanocomposite composed of multilevel nanostructure with ultrathin CuxO nanoflakes anchored on Cu2O nanowires, directly on Cu foil and its application as non-enzymatic glucose sensor. Due to more active sites endowed by the ultrathin CuxO nanoflakes, the as-prepared CuxO nanoflakes/Cu2O nanowires@Cu nanoarray exhibit high sensitivity (3.59 mA mM−1 cm−2), low detection limit (0.69 μM), high selectivity, fast amperometric response (~ 2 s) and excellent reliability in human serum. And the sensitivity of ultrathin CuxO nanoflakes/Cu2O nanowires@Cu nanoarray was 1.9-fold than that of Cu2O nanowires@Cu nanoarray. Such novel multilevel nanoarray synthesized by convenient method provides a facile way to design metal oxide nanomaterial for promising non-enzymatic glucose sensor. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) nanocomposites, based on graphene and transition metal oxides, hold great promise as high-performance electrode materials for next-generation lithium-ion batteries. Herein, a novel 2D CuO/RGO has been constructed by CuO ultrathin nanosheets and reduced graphene oxides (RGO) through in-situ oxidizing the Cu/RGO nanocomposite with hydrogen peroxide. CuO nanosheets with a thickness of 1.17–1.57 nm are uniformly and tightly anchored on the RGO surface without aggregation and thus the as-prepared CuO/RGO nanosheets electrode show strong interfacial coupling and fast electron transfer. Electrochemical characterizations reveal that the CuO/RGO nanocomposite electrode exhibits a remarkably enhanced cycling performance and rate performance. At the current density of 0.1C, the initial discharge capacity of 811 mAh/g has been delivered by CuO/RGO nanosheets electrode and the coulombic efficiency maintains 99.44% after 100 cycles. Moreover, the CuO/RGO nanosheets exhibit a stable specific capacity of 386 mAh/g after 200 cycles at 3C. In addition, the as-prepared CuO/RGO nanocomposite electrode exhibited excellent rate performance and lower charge transfer resistance. The current study presents a feasible route to fabricate nanosheets electrode materials for next-generation energy storage devices. Image 1 • CuO ultrathin nanosheets was synthesized through in-situ oxidizing approach. • CuO nanosheets are uniformly and tightly anchored on the RGO surface. • CuO/RGO nanosheets show strong interfacial coupling and fast electron transfer. • CuO/RGO anode exhibits a remarkably enhanced cycling and rate performance. [ABSTRACT FROM AUTHOR]

Graphical abstract A one-pot approach was applied for ultrafine Ag nanoparticles-hydrogel composites with excellent catalytic performance for the reduction of 4-nitrophenol. Highlights • A one-pot synthesis method was developed for the preparing of Ag-hydrogel composite. • The crosslinking of hydrogel and reduction of Ag was completed simultaneously. • Ag with a size of 2.47 ± 0.26 nm were well dispersed in the hydrogel network. • Ag-hydrogel exhibits excellent catalytic performance for the reduction of 4-NP. Abstract Ultrafine Ag nanoparticles with unique physicochemical properties have a wide potential catalytic application. Herein, a one-pot method based on UV irradiation was applied for the synthesis of Ag-hydrogel composite, in which ultrafine Ag nanoparticles with a mean size of 2.47 ± 0.26 nm were well dispersed in the hydrogel network. In addition, the as-prepared Ag-hydrogel composites showed great catalytic performance and stability in the reduction of 4-nitrophenol. [ABSTRACT FROM AUTHOR]

The activity of heterogeneous catalysis depends on charge transfer from catalyst surface to adsorbed molecules. Thus the influence of nanoparticle‐loaded heterostructures and core‐shell heterostructures on photocatalytic performance is significant to be demonstrated. In this work, Cu–Cu2O heterostructures were controllably synthesized by in‐situ reduction of Cu nanoparticles from octahedral Cu2O crystals and forming nanoparticle‐loaded heterostructures (partial coverage I and partial coverage II) and the core‐shell heterostructure (full coverage) by controlling the reaction time. The results indicate that optimal size and quantity of the loaded nanoparticles are required to attain the desirable performance by effectively separating and transferring photo‐excited carriers. Here we report a controllable two‐step synthesis method to design and fabricate Cu–Cu2O heterostructures, including the nanoparticle‐loaded structure and the core‐shell structure. It was found that optimal size and quantity of the loaded Cu nanoparticles could attain best photocatalytic performance. [ABSTRACT FROM AUTHOR]

Pt decorated yolk–shell Cu2O cubes are obtained using a surfactant-free and multiple-step method. Porous yolk–shell cubic structures, together with synergistic effects between Pt and Cu2O, endow the yolk–shell Pt–Cu2O based nonenzymatic H2O2 sensors with enhanced sensing performance. [ABSTRACT FROM AUTHOR]

A facile Cu 2 O-templated approach is demonstrated for the synthesis of hierarchical Ag-AgBr hollow nanucubes. The structural and morphological characterizations show that the as-prepared hollow Ag-AgBr nanocubes consist of dense nanotips, which exhibited an excellent photocatalytic activity under visible light due to the strong surface plasmon resonance (SPR) of Ag nanosturctures and the synergistic effect between Ag and AgBr. The photodegradation ability was evaluated by the degradation of the methyl orange (MO) dye under visible-light irradiation, showing that more than 90% of the MO could be decomposed in 20 min. [ABSTRACT FROM AUTHOR]

Facile synthesis of ultrathin two-dimensional metallic nanosheets with special physical and chemical properties is still challenging. In this work, ultrathin silver nanosheets were synthesized through the galvanic replacement reaction between silver nitrate and Cu microcages without using any surfactant at room temperature. The as-prepared Ag nanosheets (NSs) were concave and had a thickness of sub-10 nm. And the nanosheets exhibited excellent H 2 O 2 detection property with a high sensitivity of about 320.3 uA mM −1 cm −2 and a low detection limit of 0.17 µM in a wide linear range of 5–6000 μM, and a fast response time (less than 2 s). Besides, the real-time detection of H 2 O 2 induced from living HeLa and SH-SY5Y cells were also achieved, indicating the potential application of as-prepared Ag NSs in monitoring physiological and dynamic in-clinic pathological processes. [ABSTRACT FROM AUTHOR]

In this study, a template-assisted approach for novel hierarchical CuO nanoflowers with Cu 2 O nanocubes as the templates was designed and carried out. The structures and morphologies in different growth processes were studied by various characterization methods, showing that these hierarchical CuO nanoflowers consisted of ultrathin nanosheets. The hierarchical CuO nanoflowers serving as active materials illustrated great performances for non-enzymatic glucose sensing with high sensitivity of 2217 μA mM −1  cm −2 , low detection limit of 0.96 μM and wide linear range up to 6 mM. Moreover, the electrodes exhibited quick response time, long term stability, good selectivity and acceptable practice workability, suggesting the great potential of the as-prepared CuO nanoflowers in non-enzymatic glucose sensors. [ABSTRACT FROM AUTHOR]

Design and synthesis of binder-free electrodes with active nanomaterials on the surface are expected to enhance electrochemical properties. In the work, a novel thin film formed by assembled CuO nanosheets and ultra-thin Cu 2 O film directly adhered on copper foil was obtained by just simply oxidizing the Cu foil using H 2 O 2 . The obtained product on Cu foil consists of a film assembled by CuO/Cu 2 O nanosheets. The ultrathin CuO nanosheets with large surface area provide adequate active sites for the electrocatalysis and the strong binding will promote the electron transfer between active nanomaterials and Cu substrate. The electrochemical performance shows that this novel structure as an electrode exhibits excellent properties for the non-enzyme glucose sensor, with an ultrahigh sensitivity of 1.541 mA mM −1 cm −2 , a low detection limit of 0.57 μM and the linear range is up to 4 mM. Good stability and high selectivity were also obtained by using CuO/Cu 2 O nanosheets@Cu as a nonenzymatic glucose sensor, and furthermore, the electrode shows powerful reliability for analyzing human serum samples. Therefore, the CuO/Cu 2 O film based on Cu foil binder-free electrode may become a promising nonenzymatic glucose sensor and the work also provides a strategy for the design of electrochemical electrode. [ABSTRACT FROM AUTHOR]

We have demonstrated a facile Cu2O-templated approach for the synthesis of nanoparticle-aggregated hollow copper microcages (HCMC). As substrates, these HCMC exhibit surface enhanced Raman scattering (SERS) activity for rhodamine 6G (R6G) and 4-mercaptobenzoic acid (4-MBA). [ABSTRACT FROM AUTHOR]

Herein, Cu nanowires are utilized as a self-sacrificial template to synthesize CuO hollow nanotubes (HTs) by a facile wet chemical method. The HTs with a diameter 549 ± 83.6 nm and rough surface, are constructed by well-distributed curved ultrathin nanosheets. When employed as an anode electrode in Li-ion batteries, the resulting CuO HTs exhibited a high specific capacity of 736 mAh g−1, superior rate performance and high cyclic performance. The excellent electrochemical performance of CuO HTs can be attributed to the high specific surface area, abundant unimpeded diffusion paths and high electron transfer rate due to the unique two-dimensional nanosheets structure and hollow structure. Moreover, the hollow structure provides enough space to accommodate volumetric changes and structural strain during the charge/discharge process, resulting in excellent cyclic stability. The current report presents a novel strategy to develop high-performance anodes for next-generation Li-ion batteries. Image 1 • CuO hollow nanotubes was synthesized using a simple method. • The tube surface is constructed by well-distributed curved ultrathin nanosheets. • The electrode demonstrates high capacity of 736 mAh g−1. [ABSTRACT FROM AUTHOR]

In this paper, Fe10Co25Ni34Cu23Al8 high-entropy-alloy nanoparticles have been synthesized by the in situ instantaneous electrical wire explosion method. Based on the thermodynamic parameters of the face-centered cubic phase of high-entropy-alloy, the parameters of the five kinds of wires were calculated and controlled, and the stable face-centered cubic structure with good crystallinity was synthesized in one step. The influence of the energy deposition during the electrical explosion on the nanoparticles and their electromagnetic absorption performance was explored. The results show that the face-centered cubic structure high-entropy-alloy with high crystallinity has better electromagnetic wave absorption performance when the energy deposition of the wires is increased. The minimum reflection loss can reach −39.37 dB at 15.34 GHz when the thickness is 1.9 mm and the effective absorption bandwidth is 6.63 GHz. It can provide a strategy for the microstructure and morphology design of high-entropy-alloy nanoparticles in electromagnetic wave absorption and magnetism in the electronics industry. [ABSTRACT FROM AUTHOR]

With the rapid development of industries, the emission of volatile organic compounds (VOCs) produced by various chemical projects has been deteriorating the surrounding ecological environments and health of human being. Photocatalysis is an economic approach to solve environmental problems by using light irradiation to kick off chemical reactions under the action of photocatalysts. Owing to a narrow band gap, suitable redox potential, and high chemical stability, graphite carbon nitride (g-C 3 N 4) has been widely adopted for performing cost-effective photocatalysis. However, the rapid recombination of electrons (e−) and holes (h+) on pure g-C 3 N 4 leads to its poor photocatalytic activity. To alleviate this shortcoming, g-C 3 N 4 has been reported in composite form (doped with other nanomaterials: carbon, metal, oxide, ion doping etc.) Herein, we review detail research progress of four g-C 3 N 4 -based photocatalytic nanocomposites for the degradation of VOCs. Finally, we propose a scope for future research work for fabricating advanced g-C 3 N 4 -based heterostructure composite photocatalysts to treat VOCs admission. [Display omitted] [ABSTRACT FROM AUTHOR]

The controlled growth of Cu2S nanoarrays was constructed by a facile two-step impregnation synthesis route. The as-synthesized Cu2S/CuO@Cu samples were precisely characterized in terms of surface morphology, phase, composition, and oxidation states. At the laser irradiation of 808 nm, Cu2S/CuO@Cu heated up to 106 °C from room temperature in 120 s, resulting in an excellent photothermal conversion performance. The Cu2S/CuO@Cu exhibited excellent cycling performance—sustaining the photothermal performance during five heating-cooling cycles. The finite difference time domain (FDTD) simulation of optical absorption and electric field distributions assured the accuracy and reliability of the developed experimental conditions for acquiring the best photothermal performance of Cu2S/CuO@Cu. [ABSTRACT FROM AUTHOR]

Cu2O cubes and octahedra which have different crystallographic facets have been used for the nonenzymatic glucose sensors. The electrode based on the Cu2O octahedra displays much higher sensitivity, wider linear range and lower detection limit than that of the cubes modified electrode, which could be attributed to the different atomic arrangements of the exposed surface. [ABSTRACT FROM AUTHOR]

Designing highly active material to fabricate a high-performance noninvasive wearable glucose sensor was of great importance for diabetes monitoring. In this work, we developed CuxO nanoflakes (NFs)/Cu nanoparticles (NPs) nanocomposites to serve as the sensing materials for noninvasive sweat-based wearable glucose sensors. We involve CuCl2 to enhance the oxidation of Cu NPs to generate Cu2O/CuO NFs on the surface. Due to more active sites endowed by the CuxO NFs, the as-prepared sample exhibited high sensitivity (779 μA mM−1 cm−2) for noninvasive wearable sweat sensing. Combined with a low detection limit (79.1 nM), high selectivity and the durability of bending and twisting, the CuxO NFs/Cu NPs-based sensor can detect the glucose level change of sweat in daily life. Such a high-performance wearable sensor fabricated by a convenient method provides a facile way to design copper oxide nanomaterials for noninvasive wearable glucose sensors. [ABSTRACT FROM AUTHOR]

The geometries, electronic structures, and bonding properties of the title endohedral Zintl clusters have been studied by using ab initio calculations. [Fe@Ge10]4− and [Co@Ge10]3− have D5h‐symmetric pentagonal prismatic structure and [Fe@Sn10]4− adopts the C2v‐symmetric structure as their ground‐state structures, whereas all the other clusters possess D4d bicapped square antiprismatic structures, in consistent with the experimental values when available. Natural bonding orbital and electron localization function disclosed that the negative charges are localized on the central atoms rather than the cages while the TME ionic bonding interactions increase in the order of Ge < Sn < Pb. The energy decomposition analysis revealed that the total bonding energy ∆Eint between central TM and E10 cage is above 150 kcal/mol. The ionic bonding interaction termed as electrostatic interaction ∆Eelstat increases in the order of Ge < Sn < Pb and becomes higher than the covalent bonding interactions termed as total orbital interactions ∆Eorb. Among the total orbital interactions, the π back donations from the TM–d orbitals to the empty cage orbitals consisting of E‐p orbitals, the magnitude of which is importantly affected by the cage symmetry, are dominant contributions. [ABSTRACT FROM AUTHOR]

Dielectric capacitors, as one of the important electronic devices, are widely used in various fields. However, most ferroelectric capacitors with high energy storage density require excessively high electric fields. In this work, we have prepared 0.9(Bi0.5Na0.5)0.7Sr0.3TiO3-0.1 Bi(Mg2/3Nb1/3)O3 relaxor ferroelectric ceramics with different BaZrO3 doping levels. A high energy storage (Wr) of 4.07 J/cm3 and efficiency (η) of 91% are simultaneously obtained in 0.94[0.9(Bi0.5Na0.5)0.7Sr0.3TiO3-0.1 Bi(Mg2/3Nb1/3)O3]-0.06BaZrO3 ceramic under a medium electric field of 260 kV/cm. Additionally, the ceramic also exhibits excellent temperature and frequency stability. Furthermore, the phase field simulation is used to simulate the evolution of domain structure and hysteresis loops of the ceramics with different doping levels. The results of phase field simulation explicitly explain the influence of different relaxation degrees on energy storage density and efficiency of the ceramics. We believe that the ceramic prepared in this work is one of the most promising candidate materials for some miniaturized energy storage devices operating under low or medium electric fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cobalt doped carbon nitride activated peroxymonosulfate effectively, achieving 97% toluene removal rate; • Doped cobalt atoms in carbon nitride significantly improved the production of reactive oxygen species; • Cobalt atoms accelerated the electron transfer during the peroxymonosulfate activation process; • Singlet oxygen was the dominant reactive oxygen species (ROS) in both the degradation and mineralization of toluene. Degradation of gaseous volatile organic compounds (VOCs) under mild conditions is a great challenge. In this work, we doped Co atoms in carbon nitride (CN) to form Co/CN (CCN) catalyst with Co-N configuration. The CCN catalyst exhibited higher toluene degradation efficiency (97 %) than that of the CN/PMS system (27 %) via peroxymonosulfate (PMS) activation, and exhibited high toluene removal efficiency (>90 %) within 7 days. Electron paramagnetic resonance (EPR) and radical quenching tests suggested that singlet oxygen (1O 2) was the dominant reactive oxygen species (ROS) in both the degradation and the mineralization of toluene. Density functional theory (DFT) study indicated that the electron transfer from Co atoms to PMS contributed to the generation of ROS. This work proposed a new perspective on the use of Co doped catalyst in liquid phase advanced oxidation processes (AOPs) for low-temperature VOCs removal technology. [ABSTRACT FROM AUTHOR]

A stable catalyst derived from waste sources has been effectively produced for the elimination of TC. The catalyst was prepared by pyrolysis of waste ore loaded onto porous biochar (BC), which improved the activation efficiency of peroxymonosulfate (PMS). The catalyst was found to contain BC and metal oxides (Fe, Co, Mg) based on the results of the characterization tests. Under optimal reaction conditions, the catalyst degraded 96.59% of TC (20 mg/L) within 60 min. Pseudo-first-order kinetic pattern was fitted on TC degradation with a rate constant of 0.028 min−1. After five cycles, the degradation efficiency was determined to be 92.55%, while the structure and physicochemical properties of the catalyst remain unchanged. Furthermore, the composite can be separated and recovered through magnetic means. In addition, based on EPR and free radical quenching experiment, PMS activated by waste ore/BC produced sulfate radical (SO 4 •-), hydroxyl radical (HO•), singlet oxygen (1O 2) and superoxide radical (•O 2 -). Among them, SO 4 •- and HO• played the most significant roles in TC degradation. This work provides an insight into waste resource utilization and antibiotic contamination removal. [Display omitted] • A composite catalyst is derived form waste ore, sludge and pine needle. • The catalyst (waste ore/BC) has good magnetic properties and reusability. • The waste ore/BC+PMS system exhibits favourable performance for tetracycline degradation. [ABSTRACT FROM AUTHOR]

As competitive photocatalysts, Cu 2 O nanoparticles meet with severe photogenerated carries recombination and insufficient light absorption, leading to the poor photocatalytic performance. Herein, the truncated Cu 2 O-Au (CA) binary and Cu 2 O-Au-TiO 2 (CAT) ternary octahedra with Au nanoparticles (Au NPs), preferentially supported on the (110) and (100) planes of Cu 2 O, are synthesized for efficient photocatalytic degradation reactions. The photodegradation rates of MO of CA1 (Cu 2 O-Au containing 1 wt % Au) and CAT are as high as 95.61% and 96.5% under 60 min of visible light irradiation, respectively. On the one hand, the synergistic function of localized surface plasmon resonance (LSPR) of Au NPs and Schottky barrier accelerate the separation and transfer of photogenerated carriers. On the other hand, a Z-scheme electron transfer system is constructed in CAT to promote the photodegradation performance. According to the finite-difference-time-domain (FDTD) simulation result, there is a strong electric field enhancement at the contact sites between Au, Cu 2 O and TiO 2 , which accelerates the electron transfer to a large extent and separates the electron-hole pairs. Therefore, this work may provide an approach for the synthesis and applications of multiple heterostructure catalyst. [ABSTRACT FROM AUTHOR]

A systematic first‐principles study is performed to investigate the 20‐electron transition metal complexes (C5H5)2TM(E1E2)2 (TM = Cr, Mo, W; E1E2 = CO, N2, BF). For the thermodynamic stable (C5H5)2TM(E1E2)2 complexes (TM = Cr, Mo, W; E1E2 = CO, BF), their 20‐electron nature is derived from their occupied nonbonding molecular orbital mainly donated by ligands. Furthermore, the nature of the TME1 bond is thoroughly analyzed by the energy decomposition analysis (EDA) method. The absolute value of interaction energies (|ΔEint|) between (C5H5)2TM(E1E2) and E1E2 has the same trend as the corresponding bond dissociation energy and Wiberg bond orders of TME1 bonds, following the order W > Mo > Cr with same ligands and BF > CO with same TM. The largest contribution to the ΔEint values is the repulsive term ΔEPauli. Similar contributions from covalent and electrostatic terms to the TME1 bonds are found, which can be described as the classic dative bond with nearly same σ and π contributions. [ABSTRACT FROM AUTHOR]

Atomically ordered Rh2P nanoclusters encapsulated within a high-surface-area hollow mesoporous carbon nanoreactor are catalytically active for hydrogen production via the electrocatalytic hydrogen evolution reaction and the room-temperature dehydrogenation of ammonia borane. [ABSTRACT FROM AUTHOR]

An etching-limited branching growth mechanism has been elucidated during ethanol-assisted solution synthesis of octahedral Cu2O crystals, which is different from the conventional diffusion-limited aggregate and recent overpotential-limited branching mechanism. It provides an innovative approach for revealing the shape evolution from habit formation (octahedron) to branching growth (hexapod-like architecture) viaadjusting the competition between preferential growth and selective oxidative etching, and displays a constructive model system for fundamental research of crystal growth and design. [ABSTRACT FROM AUTHOR]

Herein, a facile seed‐assisted strategy for preparing Cu nanoparticles (NPs) with polyvinyl pyrrolidone (PVP) capping is presented. Compared to the Cu NPs with deficient PVP protection, the Cu NPs capped with a sufficient amount of PVP remain almost completely as Cu0 species. In contrast, the Cu NPs that are considered PVP deficient form an oxide structure in which the inner layer is face‐centered cubic Cu and the outer layer is, at least in part, made up of Cu2O species. Furthermore, to eliminate CO2 molecule diffusion and simultaneously obtain significant current density (200 mA cm−2) for industrial applications, a flow cell configuration is used for carbon dioxide electro reduction reaction (CO2RR) testing in 0.5 m potassium hydroxide solution. The Cu NPs with zero valence deliver Faradaic efficiencies (FEs) for the CO2 reduction to CH4 of over 70%, with a current density exceeding 200 mA cm−2, outstripping the performances of the majority of the reported CO2 electrocatalysts. Interestingly, the distribution of products catalyzed by the Cu NPs with +1 valence includes multicarbon products (C2+) such as C2H4, C2H5OH, CH3COOH, and C3H7OH with combined FEs of >80%, with current densities of up to 300 mA cm−2. The above results unambiguously establish that surface oxidation of Cu species plays a crucial role in the CO2RR. [ABSTRACT FROM AUTHOR]

This study demonstrates fabrication of FeCoNi magnetic nanoparticles by joint electrical explosion of wires for electromagnetic wave absorption applications. An increase in the energy storage capacity of the capacitors can increase the maximum reflection loss of the nanoparticles and shift the corresponding frequency in the low-frequency direction, but has no significant effects on the maximum bandwidth. The minimum reflection loss of the magnetic nanoparticles reaches − 50.2 dB at 6.8 GHz when the thickness is 2.5 mm, while the maximum effective absorption bandwidth reaches 8.1 GHz at a thickness of 1.5 mm. The wire explosion method, as an instantaneous synthesis method with a low cost, environmental friendliness, and high-output characteristics, provides a new approach to industrial batch preparation of microwave-absorbing materials. • Magnetic alloy nanoparticles FeCoNi successfully obtained by joint electrical wires explosion. • More uniform particles composition can be achieved by increasing discharge energy. • The maximum reflection loss is − 50.2 dB at 2.5 mm and the absorption bandwidth (<−10 dB) is 8.1 GHz at 1.5 mm. [ABSTRACT FROM AUTHOR]

The coordination of 10‐electron diatomic ligands (BF, CO N2) to iron complexes Fe(CO)2(CNArTripp2)2 [ArTripp2=2,6‐(2,4,6‐(iso‐propyl)3C6H2)2C6H3] have been realized in experiments very recently (Science, 2019, 363, 1203–1205). Herein, the stability, electronic structures, and bonding properties of (E1E2)Fe‐(CO)2(CNArTripp2)2 (E1E2=BF, CO, N2, CN−, NO+) were studied using density functional (DFT) calculations. The ground state of all those molecules is singlet and the calculated geometries are in excellent agreement with the experimental values. The natural bond orbital analysis revealed that Fe is negatively charged while E1 possesses positive charges. By employing the energy decomposition analysis, the bonding nature of the E2E1–Fe(CO)2(CNArTripp2)2 bond was disclosed to be the classic dative bond E2E1→Fe(CO)2(CNArTripp2)2 rather than the electron‐sharing double bond. More interestingly, the bonding strength between BF and Fe(CO)2(CNArTripp2)2 is much stronger than that between CO (or N2) and Fe(CO)2(CNArTripp2)2, which is ascribed to the better σ‐donation and π back‐donations. However, the orbital interactions in CN−→Fe(CO)2(CNArTripp2)2 and NO+→Fe(CO)2(CNArTripp2)2 mainly come from σ‐donation and π back‐donation, respectively. The different contributions from σ donation and π donation for different ligands can be well explained by using the energy levels of E1E2 and Fe(CO)2(CNArTripp2)2 fragments. [ABSTRACT FROM AUTHOR]

A rhombicuboctahedral (26-facet) Cu2O single crystal, generally with well-developed {100}, {110} and {111} crystallographic planes, has attracted considerable attention due to its faceted synergistic effects in catalysis, sensing, and energy conversion. However, the electrocatalytic performance of the 26-facet Cu2O single crystal can be severely limited by its large size and low-active smooth surface, since it is quite difficult to prepare high-active 26-facet Cu2O nanocrystals exposed with rough surfaces. In this article, we successfully prepared jagged 26-facet Cu2O nanocrystals with clean facets at room temperature via a facile Mn2+ mediated aqueous phase reduction method. The shape-evolution and growth mechanism of rhombicuboctahedral Cu2O nanocrystals enclosed by jagged surfaces are also proposed, which might be attributed to a sequential dissolution–precipitation–surface reforming mechanism. These unique jagged 26-facet nanocrystals exposed with more active sites can exhibit superior glucose-sensing performance than those of the traditional 26-facet Cu2O microcrystals enclosed by smooth surfaces. With the merits of facile control as well as relatively high activity, it could provide a good prospect for the surfactant-free synthesis of other metal oxides with well-defined crystal planes. [ABSTRACT FROM AUTHOR]

Graphene is expected to comprehensively improve the thermal conductivity and corrosion resistance of metals to satisfy the need of adverse electrochemical environments. However, there are some major concerns in the mixing methods such as, low quality of graphene, non-uniform dispersion, and poor interface bonding with the metal matrix. In this study, we propose an effective approach to fabricate Cu-graphene (Cu/G) nanocomposite by sintering in-situ growth of graphene on Cu nanoparticles. Results confirmed the firmly adhesive graphene on Cu surface, which closely linked Cu particles to building a bulk, particularly binding between Cu particles and graphene flakes is largely improved by the sintered progress. The as-prepared Cu/G heat spreader demonstrated higher thermal conductivity (376 W/(m·K) at room temperature and lower thermal expansion. Additionally, the short-time corrosion resistance showed that Cu/G can build a graphene network to avoid the penetration of active species and enhance the passivation layer. This work endows Cu/G integral materials possessing good thermal conductivity and corrosion inhibition, which can effectively serve as potential offshore materials. [Display omitted] • Cu/G nanocomposite was fabricated by sintering in-situ growth of graphene on Cu. • Cu/G demonstrated higher thermal conductivity and lower thermal expansion. • Graphene network in the Cu/G nanocomposite reinforced the passivation layer. • Cu/G nanocomposite showed higher corrosion resistance. [ABSTRACT FROM AUTHOR]

AgPt bimetallic hollow nanoparticles (AgPt-BHNPs) with an ultra-thin shell were synthesized. They show obvious localized surface plasmon resonance (LSPR) effects on electrocatalytic activity and CO poisoning tolerance in the methanol oxidation reaction (MOR) in alkaline media, which is attributed to the LSPR-induced localized photothermal effects and LSPR induced surface charge heterogeneity. [ABSTRACT FROM AUTHOR]

Integration of highly-active nanoscale metal-based components into unique skeleton materials to enhance their intrinsic properties is significant for the cost-efficient application of catalyst. Here, two sisal fiber templates with different structure were chemically obtained and employed as the supporters to immobilize nickel nanoparticles by electroless deposition method in nickel bath. The coating of nickel nanoparticles (NPs) inherited preferably the micromorphology of fiber with lumen and surface micro convex structure. Compared to sisal fiber bundle (SFB), elementary sisal fibers (ESFs) afford a superior deposited substrate for Ni NPs, which exhibit highest catalytic rate constant 16.14 × 10 −3  s −1 and turnover frequency 1.82 × 10 −3 mol mol −1  s −1 at 20 °C and molar ratio of NaBH 4 : p -NP (100) for reduction of p- NP with only 3.39 wt.% Ni. The outstanding performance of Ni/ESFs obtained here can be assigned to the high content of metallic nickel in nanoparticles, the flexible fiber based 3D network and the synergistic effect of Ni NPs and ESFs. Ni/ESF catalysts were also successfully applied for the catalytic hydrogenation of methyl orange (MO) and Rhodamine B (RhB). Moreover, present catalyst further exhibited excellent reusability derived from their stable physic-chemical structure and magnetically separable feature in the catalytic reaction. As a result, supported by the widely-available sisal fiber templates with tailored structures, present catalysts show the certain superiority in cost-effective hydrogenation of refractory aromatic pollutants compared to the catalysts reported in the literatures. [ABSTRACT FROM AUTHOR]

Bi 2 W x Mo 1-x O 6 /g-C 3 N 4 were prepared by a simple one-step hydrothermal method to adjust the energy band of Bi 2 W x Mo 1-x O 6 solid solution and promote the separation of electron-hole pairs under visible light to generate hydroxyl radical and superoxide radical for efficient oxidation of HCHO. [Display omitted] • Element Mo replaced W to form Bi 2 W x Mo 1-x O 6 solid solution to adjust energy band. • 2D/2D Bi 2 W x Mo 1-x O 6 /g-C 3 N 4 was prepared via one-step hydrothermal method. • Bi 2 W x Mo 1-x O 6 /g-C 3 N 4 exhibited favorable efficiency for HCHO degradation. • Z-scheme heterojunction was formed to enhance the conversion of HCHO. In this work, 2D/2D Bi 2 W x Mo 1-x O 6 /g-C 3 N 4 was synthesized via surfactant-assisted one-step hydrothermal method for the degradation of formaldehyde in simulated room environment. We utilized CTAC as surfactant to control the morphologies of Bi 2 W x Mo 1-x O 6 coupling with g-C 3 N 4 nanosheets. In the hydrothermal method, Mo replaced W to form solid solution which could reduce energy band gap of Bi 2 WO 6. In contrast to Bi 2 W 0.6 Mo 0.4 O 6 (43.1%) and g-C 3 N 4 (23.2%), Bi 2 W 0.6 Mo 0.4 O 6 /g-C 3 N 4 exhibited superior activity (92.4%) of photocatalytic degradation for formaldehyde at the initial concentration of 1 ppm under the relative humidity (RH) of 20%. Meanwhile, we simulated diverse typical indoor conditions to evaluate the applicability of catalysts. More importantly, Bi 2 W 0.6 Mo 0.4 O 6 /g-C 3 N 4 performed satisfactory stability with 5.5% decrease in degradation efficiency after five cycles. The mechanism of enhanced HCHO conversion was ascribed to the formation of 2D/2D Z-scheme heterojunction between Bi 2 W 0.6 Mo 0.4 O 6 and g-C 3 N 4 which increased the accessible interface and promoted the separation of photo-generated carriers for oxidation of formaldehyde. [ABSTRACT FROM AUTHOR]

The citrate sol-gel method was used to synthesize LaNi 0.6 Co 0.4 O 3 anchored at ZnO (LaNi 0.6 Co 0.4 O 3 /ZnO) for activation of peroxymonosulfate to degrade ofloxacin in simulated wastewater. LaNi 0.6 Co 0.4 O 3 nanoparticles were uniformly and firmly dispersed on ZnO support during the synthesis process. LaNi 0.6 Co 0.4 O 3 /ZnO had a rapid catalytic rate with an efficiency of 90% in 10 min, which was higher than that of LaNi 0.6 Co 0.4 O 3 (87.7%). Meanwhile, LaNi 0.6 Co 0.4 O 3 /ZnO significantly inhibited metal ion leaching compared to LaNi 0.6 Co 0.4 O 3 (Ni leaching: 0.128 mg/L to 0.022 mg/L, Co leaching: 0.083 mg/L to 0.012 mg/L). The composite material maintained great cyclic stability with efficiency of 93% after 5 cycles. Based on electron paramagnetic resonance studies and the quenching experiments, SO 4 ·− 、 · OH、 · O 2 − and 1O 2 were the main reactive oxygen species involved in the reaction. The degradation intermediates of ofloxacin were detected by ICP-MS to propose the possible degradation pathways. This work provides an insight for perovskite catalyst for the activation of PMS to treat pharmaceutical wastewater. [Display omitted] • LaNi 0.6 Co 0.4 O 3 nanoparticles are uniformly and firmly dispersed on ZnO support. • LaNi 0.6 Co 0.4 O 3 /ZnO exhibits favorable catalytic activity. • LaNi 0.6 Co 0.4 O 3 /ZnO possesses excellent stability with inhibition of metal leaching. [ABSTRACT FROM AUTHOR]

We synthesized the magnetic recyclable Ti 3 C 2 derived N-TiO 2 @C@Fe 3 O 4 for photo-Fenton degradation of organic pollutants through high-temperature calcination and solvothermal methods. Ti 3 C 2 was first calcined into TiO 2 @C with a homogeneous titanium source and a two-dimensional carbon framework. Then the magnetic nanoparticles (Fe 3 O 4) were loaded by solvothermal method, which effectively solved the problem of repeated circulation of powder catalysts. N-TiO 2 @C@Fe 3 O 4 could be used as an excellent co-catalyst to improve the decomposition efficiency of H 2 O 2 in advanced oxidation processes (AOPs). This significantly reduced the amount of H 2 O 2 and Fe2+ in the photo-Fenton system. The N-TiO 2 @C@Fe 3 O 4 photo-Fenton system could degrade 96.5% of Rhodamine B (RhB) within 300 s and maintain a recycling rate of more than 90% after 10 cycles. This system also had favorable applicability to the same wastewater of antibiotics. This mechanism was proposed that the N-TiO 2 @C@Fe 3 O 4 photo-Fenton system activated H 2 O 2 to generate hydroxyl radicals (·OH) and superoxide radicals (·O 2 −) to further attack RhB. This research provided novel insights for the photo-Fenton collaborative catalytic system to achieve advanced oxidation treatment of pollutants in the water environment. Magnetically recoverable Ti 3 C 2 -derived N-TiO 2 @C@Fe 3 O 4 had been successfully designed for photo-Fenton degradation of refractory organic pollutants in water by high-temperature calcination and solvothermal methods. N-doped TiO 2 effectively reduced the bandgap and improved the light utilization, generating photogenerated electrons (e-) and holes (h+). The carbon matrix rapidly captured photogenerated electrons, suppressing carrier recombination and further enhancing the e-/h+ separation efficiency. The generated hydroxyl radicals (·OH) and superoxide radicals (·O 2 −) played a key role in the degradation of dyes and antibiotics. [Display omitted] • The N-doped and carbon layer reduced the band gap and improved the light utilization efficiency. • Magnetic recyclable N-TiO 2 @C@Fe 3 O 4 showed excllent cycle stability for degrading RhB. • ·OH and ·O 2 − played an important role in the optical Fenton process. • The mechanism of N-TiO 2 @C@Fe 3 O 4 photo-Fenton system to degrade RhB was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of ultrasmall Pt NPs with improved sintering resistance. • Boron doping into carbon contributes to the enhanced metal-support interaction. • The method is extended to prepare PtM (M = Co, Fe, Ni, Cu) alloy NPs. • The catalysts exhibit enhanced ORR activity and stability. Insufficient thermal and electrochemical stability is a large challenge for carbon-supported Pt-based nanoparticles (NPs) as oxygen reduction reaction (ORR) catalysts. Herein, a facile pyrolysis method is developed for the synthesis of ultrasmall Pt NPs anchored on boron-doped carbon (Pt/(B-C)). The stronger interaction between Pt and boron-doped carbon (B-C) endows catalysts with improved sintering resistance to stabilize the Pt NPs of sub-3 nm up to 700 °C. The Pt/(B-C)600 catalyst presents a mass activity (MA) of 0.30 A mg Pt −1, which is 3 times that of commercial Pt/C (0.10 A mg Pt −1). After durability test, the MA of the Pt/(B-C)600 catalyst has only decreased by 19.7% (commercial Pt/C dropped by 58.7%). This method can also be extended to prepare B-C supported Pt alloy NPs (PtM/(B-C), M = Co, Fe, Ni, Cu), which exhibit superior ORR performance. This study provides a general strategy for the synthesis of thermally and electrochemically stable carbon supported Pt-based catalysts. [ABSTRACT FROM AUTHOR]

An interesting morphology-evolution of Cu2O from cubic, edge-truncated cubic, edge- and corner-truncated octahedral, truncated octahedral, and finally to octahedral architectures was readily achieved by adjusting the concentration of hydroxyl. When evaluated for their photocatalytic performances, these polyhedral Cu2O crystals manifest shape-dependent properties. [ABSTRACT FROM AUTHOR]

A ternary flower-like Cu 2 O-Cu-Au was designed and constructed as electrochemical material for glucose detection. [Display omitted] • A unique flower-like Cu 2 O-Cu-Au ternary structure was designed. • The dendritic Cu 2 O provide abundant sites decorated by Au particles to hamper the aggregation of Au particles. • The CCAu based electrochemical electrode toward glucose shows a high sensitivity of 1.082 mAmM−1cm−2 and a low detection limit of 1.71 uM. Electrochemical non-enzyme sensors based on metal and metal oxide nanocomposites are still a new challenge and a huge potential area. In this work, a ternary flower-like Cu 2 O-Cu-Au (CCAu) was designed and constructed as electrochemical material for glucose detection. In which, under the combined action of hydroxide ions and persulfate ions, several micrometer-long radial Cu(OH) 2 branches were grown on the surface of the Cu sphere precursor. And then Au nanoparticles decorated Cu 2 O-Cu ternary nanocomposites formed by heat treatment and surface loading. As active materials for the electrochemical non-enzymatic glucose detection, the CCAu modified electrode showed a sensitivity of 1.082 mAmM−1cm−2 and a detection limit of 1.71 uM. The good performance of CCAu/GCE can be attributed to the compound and synergistic effect of Cu and Cu 2 O builds a mixed valence Cu0/Cu+, the special surface area and triple active substances with many active centers, and the dendritic structure which is conducive for the penetration of electrolyte. In addition, the CCAu electrode showed a performance comparable to that of a commercial analyzer in testing the blood glucose concentration in human serum, indicating that it has a great potential in the practical electrochemical sensors. [ABSTRACT FROM AUTHOR]

Accordion-like MXene-derived TiO 2 @C coupled with g-C 3 N 4 was synthesized via one-step calcination. This process simultaneously achieved the etch of Al layers, the generation of g-C 3 N 4 and the oxidation of Ti 3 C 2. Z-type heterojunction of TiO 2 @C/g-C 3 N 4 enhanced the separation of electron-hole pairs to activated H 2 O 2 under visible light to generate hydroxyl radical and superoxide radical for oxidation of NO. [Display omitted] • One-step calcination simultaneously achieved three processes: the removal of Al layers, the formation of g-C 3 N 4 and the oxidation of Ti 3 C 2. • TiO 2 @C/g-C 3 N 4 exhibited excellent efficiency and favorable stability for photocatalytic activation of H 2 O 2 to remove NO at ppm level. • Z-type heterojunction between TiO 2 @C and g-C 3 N 4 was confirmed to accelerate the separation of electron-hole pairs. • TiO 2 @C/g-C 3 N 4 activated H 2 O 2 under visible light to generate hydroxyl radical and superoxide radical for oxidation of NO. This work explored an effective treatment method for removing NO from simulated flue gas at normal temperature. We synthesized accordion-like MXene-derived TiO 2 @C coupled with g-C 3 N 4 (TiO 2 @C/g-C 3 N 4) via one-step calcination utilizing Ti 3 AlC 2 , fluoride salts and melamine as raw materials in CO 2 atmosphere. One-step calcination process simultaneously achieved the etch of Al layers of Ti 3 AlC 2 by molten fluoride salts, the generation of g-C 3 N 4 with melamine as precursor and the oxidation of Ti 3 C 2 by CO 2. TiO 2 @C/g-C 3 N 4 for photocatalytic activation of hydrogen peroxide (H 2 O 2) had as high as 94.0% removal rate of NO at parts per million level in a normal temperature environment. This efficiency was 5.3 times and 8.0 times that of TiO 2 @C/g-C 3 N 4 and H 2 O 2 individually, due to the synergy between photocatalysis and H 2 O 2 oxidation. Meantime, TiO 2 @C/g-C 3 N 4 exhibited an enhanced performance compared with g-C 3 N 4 (40.3%) and TiO 2 @C (64.1%) for Z-type heterojunction accelerating the separation of electron-hole pairs. The mechanism was proposed that Z-type TiO 2 @C/g-C 3 N 4 heterojunction activated H 2 O 2 under visible light to generate hydroxyl radical and superoxide radical for oxidation of NO. [ABSTRACT FROM AUTHOR]

• A high W r of 4.97 J/cm3 and an η of 84.4% are obtained in BNT-based ceramics. • The W r of 2.73 J/cm3 with η of 80.6% are obtained at 140 ℃. • A superior temperature performance compared with other typical dielectric materials. • A strategy of precisely adjusting the relaxation and ferroelectricity states. Dielectric energy storage materials have attracted much attention because of their wide applications in the electronics industry. However, low energy storage density and poor thermostability limit their application. In this work, a strategy was proposed to prepare lead-free relaxor ferroelectric ceramics with ultra-high energy storage properties and superior temperature stability by precisely adjusting the relaxation and ferroelectricity states and increasing the electric field intensity. An ultra-high recoverable energy storage density (W r) of 4.97 J/cm3 and an efficiency (η) of 84.4% are simultaneously obtained for the 0.95(0.9Bi 0.5 Na 0.5 TiO 3 -0.1Ba 0.85 Ca 0.15 Zr 0.1 Ti 0.9 O 3)-0.05BaSnO 3 ceramic. Moreover, a high W r of 2.73 J/cm3 with brilliant η of 80.6% are obtained in the ceramic at 140 ℃ and there is almost no thermal degradation of energy storage properties from 25 ℃ to 140 ℃. The W r and η have decreased by 2.2% and 1.9% after 105 cycles under 200 kV/cm, respectively, which demonstrates the good cycle stability of the sample. A discharge power density of up to 99.0 MW/cm3 is obtained in the 0.95(0.9Bi 0.5 Na 0.5 TiO 3 -0.1Ba 0.85 Ca 0.15 Zr 0.1 Ti 0.9 O 3)-0.05BaSnO 3 ceramic and the good charge and discharge performance of this sample is important for practical applications. [ABSTRACT FROM AUTHOR]

Manipulating Cu Nanoparticle Surface Oxidation States Tunes Catalytic Selectivity toward CH4 or C2+ Products in CO2 Electroreduction (Adv. CO 2 electroreduction, Cu nanoparticles, Cu oxidation Keywords: CO 2 electroreduction; Cu nanoparticles; Cu oxidation EN CO 2 electroreduction Cu nanoparticles Cu oxidation 1 1 1 09/27/21 20210923 NES 210923 B CO SB 2 sb Electroreduction b In article number 2101424, Xuezhi Duan, Jin Wang, Jian Yang and co-workers report an effective strategy to manipulate Cu surface oxidation states by polyvinyl pyrrolidone coverage on the surface of Cu nanoparticles. [Extracted from the article]

This work reports the Au-Cu 2 O HPs with unique inter-embedded structure bring more active sites and enhanced electromagnetic fields to enhance the hydrogen production. • Au-Cu 2 O heterostructure particles with unique inter-embedded heterostructures were controllably fabricated. • Inter-embedded Au-Cu 2 O heterostructure particles can promote much higher hydrogen generation. • The hot electrons are mainly constrained by direct electron transfer process and electromagnetic transfer for the reduction. • This inter-embedded heterostructure has more active sites and enhanced electromagnetic fields. Constructing the heterostructure with noble metals on semiconductors is recognized as a prospective approach to enhance hydrogen generation. In this study, Au-Cu 2 O heterostructure particles (HPs) with unique inter-embedded heterostructures were controllably fabricated by a universal reaction between Cu particles and HAuCl 4 solution. Besides, the boosted catalytic performance from the plasmon effects, Au-Cu 2 O inter-embedded heterostructure exhibits additional structural advantages to promote the photocatalytic property of hydrogen generation overall water splitting. Under the visible light, the H 2 evolution rate of the Au-Cu 2 O HPs is 152 and 22 times higher than that of pure Cu 2 O and traditional Cu 2 O@Au HPs with Au anchored on the surface of Cu 2 O, respectively. On one hand, inter-embedded heterostructure brings more contact areas as the active sites to carry out the direct electron transfer and electromagnetic transfer for the reduction. On the other hand, the finite difference time domain (FDTD) simulations indicate that enhanced electromagnetic fields of Au-Cu 2 O HPs form a netlike structure to maximumly accelerate the transfer of hot electrons and separate the electron–hole pairs. Under the joint action of the two, the inter-embed heterostructure exhibits superior photocatalytic property, demonstrating that this study could instruct the design of other metal–semiconductor photocatalysts. [ABSTRACT FROM AUTHOR]

• The S/Co ratio is below than 1 at. % at the heat-treatment temperature of 300 °C. • The ligand-exchange and vacuum heat-treatment are effective for surfactant removal. • The morphology and magnetic properties are preserved upon those treatments. The SmCo 5 nanoflakes covered with polyvinylpyrrolidone (PVP) surfactant are obtained via surfactant-assisted ball milling method and were treated by ligand-exchange and vacuum heat-treatment methods. No significant change in the phase structure and surface morphology of as-milled SmCo 5 nanoflakes was found upon those as confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis, respectively. Moreover, X-ray photoelectron spectroscopy (XPS) analysis revealed that the ligand-exchange and vacuum heat-treatment are effective techniques for removing the polyvinylpyrrolidone (PVP) surfactant from the surface of SmCo 5 nanoflakes. Meanwhile, the mechanism of coercivity is studied by the temperature dependence of demagnetization curves, which indicates that the magnetization reversal is controlled by co-existed mechanisms of pinning and nucleation. [ABSTRACT FROM AUTHOR]

Microfiltration membrane with anti-biofouling surface is of high importance for improving the service performance of membrane system in water treatment owing to its excellent bacteria rejection behavior. Antibacterial property is effective to enhance the anti-biofouling performance of membrane. In this work, Ag NPs were decorated on the surface of Poly(vinyl alcohol- co -ethylene) nanofibrous membrane through charge adsorption by the PDA/PEI layer on nanofiber surface. The morphology and chemical structure analysis show that the spherical Ag NPs are successfully immobilized on the nanofiber surface uniformly. The membrane present distinct rejection efficiency of pigment nanoparticles with considerable high water flux. All of Escherichia coli and Staphylococcus aureus cells can be intercepted but bovine serum albumin penetrated easily without obvious adhesion behavior to membrane surface. In addition, after attached with the membrane, above bacteria were inactive effectively with rate of 99.99%. Compared to control samples, the composite membrane presents excellent repetitive-use filtration performance after back-washing test indicating its superior anti-biofouling properties. These results can be assigned to the optimized surface of porous composite membranes synergistically determined by the network nanofiber scaffold and high active polydopamine. It is believed that the as-prepared membrane provides a new approach in treating of water body full of microbes. [ABSTRACT FROM AUTHOR]