Solar-driven CO2conversion into value-added chemical provides an attractive strategy for sustainable ***,the enhanced CO2photoreduction performance with target product selectivity remains a major ***,we develop a nove...
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Solar-driven CO2conversion into value-added chemical provides an attractive strategy for sustainable ***,the enhanced CO2photoreduction performance with target product selectivity remains a major ***,we develop a novel strategy involving Cu2O nanoparticles in situ grown on the surface of ZIF-67-derived Co@C-N nanocages(CC) to create abundant active sites and appropriate heterointerfaces.A remarkable CO selectivity of 95.7% with a yield of 117.39 μmol g-1h-1and an apparent quantum efficiency as high as 1.88% at 420 nm was obtained over CC-60 catalyst in pure water,which was 87.6 times higher than that of pure *** calculations and experiments indicated that Co@C-N nanocages as charge mediator not only rapidly trap photogenerated electrons to promote charge separation efficiency,but also regulate the d-band center of Cu atoms to move to the Fermi energy level,thereby optimizing the reaction kinetics to facilitate the highly selective conversion of the key intermediate*CO desorption to CO.
Due to its excellent biocompatibility and biodegradability,Mg and its alloys are considered to be promising materials for manufacturing of vascular ***,the manufacture of high-precision and high-performance Mg alloys ...
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Due to its excellent biocompatibility and biodegradability,Mg and its alloys are considered to be promising materials for manufacturing of vascular ***,the manufacture of high-precision and high-performance Mg alloys minitubes is still a worldwide problem with a long manufacturing processing caused by the poor workability of Mg *** solve this problem,the cyclic extrusion compression(CEC)was used to pretreat the billet by improving the workability of Mg alloys,finally shortening the manufacturing *** CEC treatment,the size of grains and second phase particles of Mg alloys were dramatically refined to 3.2μm and 0.3μm,*** after three passes of cold drawing,the wall thickness of minitube was reduced from 0.200 mm to 0.135 mm and a length was more than 1000 *** error of wall thickness was measured to be less than 0.01 mm,implying a high dimensional *** yield strength(YS),ultimate tensile strength(UTS)and elongation of finished minitube were 220±10 MPa,290±10 MPa and 22.0±0.5%,*** addition,annealing can improve mechanical property and corrosion resistance of minitubes by improving the homogeneity of the microstructure and enhancing the density of basal texture.
The application of bulk nanocrystalline Nd-Fe-B permanent magnets manufactured by hot deformation methods was severely limited by production ***,this work proposed an efficient prepa-ration method combining hot rollin...
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The application of bulk nanocrystalline Nd-Fe-B permanent magnets manufactured by hot deformation methods was severely limited by production ***,this work proposed an efficient prepa-ration method combining hot rolling and *** the melt-spun Nd-Fe-B magnetic powders as original materials,dense,large-sized,and well-uniform precursors for deformation can be obtained through cold pressing and hot *** large-sized hot-rolled magnet can be cut into small pieces and subjected to hot *** deformed magnet exhibits obvious crystallographic anisotropy,and the optimal maximum energy product can reach 35.7 ***,the mechanism of defor-mation and texture formation has been systematically studied,according to the microstructure and tex-ture characterization of different height reduction *** results indicated that there was a typical heterogeneous structure in the hot-rolled and hot-deformed Nd-Fe-B *** precipitation,grain growth,and regular grain arrangement were the main reasons for deformation and texture forma-tion during the deformation *** strategy of replacing traditional hot-pressing with large-sized hot-rolling can produce massively deformed precursors at once,greatly improving production efficiency,which is crucial for promoting the application of bulk nanocrystalline anisotropic Nd-Fe-B permanent magnets.
Silicon monoxide(SiOx) has garnered considerable attention as an anode material owing to its high ***, its commercial viability is hampered by the low conductivity and inadequate cycling stability. In this study, a ...
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Silicon monoxide(SiOx) has garnered considerable attention as an anode material owing to its high ***, its commercial viability is hampered by the low conductivity and inadequate cycling stability. In this study, a micrometer-scale silicon oxide/carbon composite(1000-SiOx/NC) was developed based on the porous and high electrical conductivity of pyrolyzed polydopamine(PDA) and the high-temperature disproportionation of SiOx. Electrochemical impedance spectroscopy(EIS) and X-ray photoelectron spectroscopy(XPS)analyses confirmed that the pyrolysis of polydopamine(PDA) not only improves electrode conductivity but also contributes to the formation of a stable solid electrolyte interface(SEI). Additionally, SiOxundergoes disproportionation reactions during the pyrolysis of PDA, further the improves the cyclic stability of the ***, the 1000-SiOx/NC composite electrode exhibited an impressive specific capacity of 783.4 mAh·g-1after 500 cycles at 1 A g-1, maintaining 80.1 % of its initial capacity. Additionally, at a high rate of 3 C, its capacity reached 607.3 mAh·g-1The synthesis approach is both straightforward and economical, offering a fresh avenue for the widespread commercial deployment of SiOx.
*** High strength and large deformability are greatly desirable for advanced structural metallic *** strengthening methods in crystalline materials rely on controlling the generation,propagation,and intersection of di...
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*** High strength and large deformability are greatly desirable for advanced structural metallic *** strengthening methods in crystalline materials rely on controlling the generation,propagation,and intersection of dislocations by introducing various internal defects[1-4].
To obtain high-entropy carbide(HEC)joints with excellent high-temperature performance,a(HfZrTiTaNb)C HEC joint featuring a direct diffusion-bonded interface with a Nb-based interlayer was successfully fabricated at re...
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To obtain high-entropy carbide(HEC)joints with excellent high-temperature performance,a(HfZrTiTaNb)C HEC joint featuring a direct diffusion-bonded interface with a Nb-based interlayer was successfully fabricated at relatively low temperatures of 1150–1250℃for 60 min under 10 *** from a modified Ni/Nb/Ni composite interlayer with a Nb content of>64 at%,an alloyed Nb_(2)Ni layer was constructed in situ by accelerating the directional diffusion of Ni atoms from the high-entropy interface into the remaining pure Nb through the Ni‒Nb eutectic ***,the excess liquid phase was squeezed out of the bonding region,ensuring the absence of Ni-based *** the intrinsic interfacial stability and sluggish diffusion effect,the HEC with its original lattice structure,was capable of developing diffusion bonding with the Nb_(2)Ni layer instead of interacting with the liquid *** high reliability of the HEC/Nb_(2)Ni bonded interface was confirmed by the coherence of(11¯3)_(HEC)//(141)_(Nb_(2))Ni and a calculated lattice misfit of *** HEC joint had a high room-temperature strength of 174 MPa because of the homogenous Nb_(2)Ni layer,which exhibited nanohardness(15.2±1.5 GPa)and an elastic modulus of 219.9±17.5 ***,the strength of the HEC joint did not decrease at 1000℃,increasing by~49%over that of HEC/Ni/HEC diffusion-bonded joints,which have stringent surface flatness *** suggested that the HEC/Nb_(2)Ni interface had excellent resistance to high-temperature softening,even though it was invariably the initial failure *** work is informative for designing bonding structures and preparing HEC components.
To shed a light on Xe bubble nucleation in U–Mo fuel from the view of primary irradiation damage,a reported U–Mo–Xe potential under the framework of embedded atom method has been modified within the range of short ...
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To shed a light on Xe bubble nucleation in U–Mo fuel from the view of primary irradiation damage,a reported U–Mo–Xe potential under the framework of embedded atom method has been modified within the range of short and intermediate atomic *** modified potential can better describe the interactions between energetic particles,and can accurately reproduce the threshold displacement energy surface calculated by the first-principles ***,molecular dynamics simulations of primary irradiation damage in U–Mo–Xe system have been conducted under different *** raise of Xe concentration brings about a remarkable promotion in residual defect quantity and generates bubbles in more overpressured state,which suggests an acceleration of irradiation damage under the accumulation of the fission ***,the addition of Mo considerably reduces the residual defect count and hinders irradiation-induced Xe diffusion especially at high contents of Xe,corroborating the importance of high Mo content in mitigation of irradiation damage and swelling behavior in U–Mo *** particular,the variation of irradiation damage with respect to contents suggests a necessity of taking into account the influence of local components on defect evolution in mesoscale simulations.
Three-dimensional(3D) electrode technology is a competitive water treatment technology owing to its high catalytic efficiency, low energy consumption, and promising development. The introduction of a third electrode o...
Three-dimensional(3D) electrode technology is a competitive water treatment technology owing to its high catalytic efficiency, low energy consumption, and promising development. The introduction of a third electrode on the basis of a 2D electrode system forms a 3D electrode system, and the introduced third electrode is also known as the particle electrode. Particle electrodes in3D electrode system are generally in the form of particles or crumbs that be filled in between the cathode and anode. The core of the3D electrode system is the particle electrode, so the selection of particle electrode materials is the focus of the research of 3D electrode technology. Carbon-based materials are widely used as particle electrodes in 3D electrode technology because of their advantages of large specific surface area, good adsorption performance, high chemical stability, and low price. In this review, the research progress of carbon-based materials as particle electrodes for degrading organic pollutants in recent years is collected, the principle of3D electrode technology is introduced, along with the classification of particle electrodes and the current research status of carbonbased particle electrodes, and the challenges and future development of carbon-based particle electrodes in wastewater treatment are summarized.
The design and fabrication of high-performance electromagnetic wave(EMW)absorbing materials are essential in developing electronic communication technology for defense and civilian *** materials function by interactin...
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The design and fabrication of high-performance electromagnetic wave(EMW)absorbing materials are essential in developing electronic communication technology for defense and civilian *** materials function by interacting with EMWs,creating various effects such as polarization relaxation,magnetic resonance,and magnetic hysteresis in order to absorb *** progress has been made to improve the dimensional performance of such materials,emphasizing the'thin,light,broad,and strong'functional ***-dimensional(1D)nanostructures are characterized by high surface area,low density,and unique electromagnetic properties,providing promising solutions to address some of the challenges in facilitating multiple reflections and wideband resonances,which are crucial for effective EMW *** paper provides an overview of recent advances in exploring 1D structures for enhancing EMW absorption and their *** design and fabrication of nanofibers,nanowires,and other 1D nanostructures are *** advantages of 1D nanomaterials in EMW absorption are also *** and future directions are discussed,focusing on developing new design concepts and fabrication methods for achieving high-performance and lightweight EMW absorbers and enhancing fundamental understanding of EMW absorption mechanisms.
The electrochemical nitrate reduction reaction(NO_(3)RR)holds promise for ecofriendly nitrate ***,the challenge of achieving high selectivity and efficiency in electrocatalyst systems still significantly hampers the m...
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The electrochemical nitrate reduction reaction(NO_(3)RR)holds promise for ecofriendly nitrate ***,the challenge of achieving high selectivity and efficiency in electrocatalyst systems still significantly hampers the mechanism understanding and the large-scale *** catalysts,comprising multiple catalytic components working synergistically,offer promising potential for improving the efficiency and selectivity of the *** review highlights recent progress in designing tandem catalysts for electrochemical NO_(3)RR,including the noble metal-related system,transition metal electrocatalysts,and pulsed electrocatalysis ***,the optimization of active sites,interfaceengineering,synergistic effects between catalyst components,various in situ technologies,and theory simulations are discussed in *** and opportunities in the development of tandem catalysts for scaling up electrochemical NO_(3)RR are further discussed,such as stability,durability,and reaction *** outlining possible solutions for future tandem catalyst design,this review aims to open avenues for efficient nitrate reduction and comprehensive insights into the mechanisms for energy sustainability and environmental safety.
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