1.Introduction Hydrogen energy can be stored and transported,which is not only one of its advantages,but also the main bottleneck in its application.Solid hydrogen storage provides an important means of storing hydrog...1.Introduction Hydrogen energy can be stored and transported,which is not only one of its advantages,but also the main bottleneck in its application.Solid hydrogen storage provides an important means of storing hydrogen energy with high density and safety.First,this method can greatly improve the hydrogen storage density.Among the three existing hydrogen storage methods,namely,high-pressure compression,liquefaction,and solidification,solid-state hydrogen storage has the highest volumetric hydrogen storage density.For example,the volumetric hydrogen storage density of MgH2 can reach 106 kg H2 per cubic meter.展开更多
Complex hydride LiAlH_(4),as a hydrogen storage material,possesses high theoretical hydrogen storage capacity(10.5 wt.%).However,highly efficient additives are urgently required to modify its thermal stability and slu...Complex hydride LiAlH_(4),as a hydrogen storage material,possesses high theoretical hydrogen storage capacity(10.5 wt.%).However,highly efficient additives are urgently required to modify its thermal stability and sluggish kinetics.Some additives exhibit unique morphology-dependent characteristics.Herein,the efficient rare earth oxide nano-CeO_(2)additives with different morphologies(nanoparticles,nanocubes,and nanorods)are prepared by the hydrothermal method,and the intrinsic properties are characterized.The three different morphologies of nano-CeO_(2),which are different in the Ce^(3+)content and specific surface area,are added to LiAlH_(4)to improve the dehydrogenation behavior.The LiAlH_(4)-CeO_(2)-nanorod composite exhibits the optimal dehydrogenation behavior,which begins to desorb hydrogen at 76.6℃ with a hydrogen capacity of 7.17 wt.%,and 3.83 wt.%hydrogen is desorbed within 30 min at 140℃.The dehydrogenation process of the composites demonstrates that hydrogen release is facilitated by the in-situ formed CeH_(2).73 and the facile transition between the oxidation states of Ce^(4+)and Ce^(3+).Combined with density functional theory calculations,the addition of nano-CeO_(2)can weaken the Al-H bond and accelerate the decomposition of[AlH_(4)]^(4-)tetrahedron,which is consistent with the reduction of the decomposition activation energy.展开更多
Aluminum hydride is a promising chemical hydrogen storage material that can achieve dehydrogenation under mild conditions as well as high hydrogen storage capacity.However,designing an efficient and cost-effective cat...Aluminum hydride is a promising chemical hydrogen storage material that can achieve dehydrogenation under mild conditions as well as high hydrogen storage capacity.However,designing an efficient and cost-effective catalyst,especially a synergistic catalyst,for realizing low-temperature and high-efficiency hydrogen supply remains challenging.In this study,the heterojunction synergistic catalyst of Ti_(3)C_(2)supported PrF_(3)nanosheets considerably improved the dehydrogenation kinetics of AlH_(3)at low temperatures and maintained a high hydrogen storage capacity.In the synergistic catalyst,Pr produced a synergistic coupling interaction through its unique electronic structure.The sandwich structure with close contact between the two phases enhanced the interaction between species and the synergistic effect.The initial dehydrogenation temperature of the composite is reduced to 70.2℃,and the dehydrogenation capacity is 8.6 wt.%at 120℃ in 90 min under the kinetic test,which reached 93%of the theoretical hydrogen storage capacity.The catalyst considerably reduced the activation energy of the dehydrogenation reaction.Furthermore,the multielectron pairs on the surface of the catalyst promoted electron transfer and accelerated the reaction.展开更多
Silicon is one of the most promising anode materials for lithium-ion batteries(LIBs), but it suffers from pulverization and hence poor cycling stability due to the large volume variation during lithiation/delithiation...Silicon is one of the most promising anode materials for lithium-ion batteries(LIBs), but it suffers from pulverization and hence poor cycling stability due to the large volume variation during lithiation/delithiation. The core-shell structure is considered as an effective strategy to solve the expansion problem of silicon-based anodes. In this paper, the double-shell structured Si@SnO_(2) @C nanocomposite with nano-silicon as the core and SnO_(2) , C as the shells is synthesized by a facile hydrothermal method.Structural characterization shows that Si@SnO_(2) @C nanocomposite is composed of crystalline Si, crystalline SnO_(2) and amorphous C, and the contents of them are 42.1wt%, 37.8 wt% and 20.1 wt%, respectively. Transmission electron microscope(TEM) observations confirm the double-shell structure of Si@SnO_(2) @C nanocomposite, and the thicknesses of the SnO_(2) and C layers are 20 and 7 nm. The Si@SnO_(2) @C electrode exhibits a high initial discharge capacity of 2777 mAh·g^(-1)at 100 mA·g^(-1)and an excellent rate capability of 340 mAh·g^(-1)at 1500 mA·g^(-1). The outstanding capacity retention is 50.2% after 300 cycles over a potential of 0.01 to 2.00 V(vs. Li/Li+) at 500 mA·g^(-1). The resistance of solid electrolyte interphase(SEI) film(Rf) and charge transfer resistance(Rct) of Si@SnO_(2) @C are 7.68and 0.82 Ω, which are relatively smaller than those of Si@C(21.64 and 2.62 Ω). It is obviously seen that the SnO_(2) shell can reduce the charge transfer resistance, leading to high ion and electron transport efficiency in the Si@SnO_(2) @C electrode. The incorporation of SnO_(2) shell is attributed to the enhanced rate capability and cycling performance of Si@SnO_(2) @C nanocomposite.展开更多
The effect of heat treatment on phase occurrence,crystal structures and hydrogen sorption properties of Y_(0.5)La_(0.2)Mg_(0.3-x)Ni_(2) compounds has been investigated.The targeted compounds were synthesized through i...The effect of heat treatment on phase occurrence,crystal structures and hydrogen sorption properties of Y_(0.5)La_(0.2)Mg_(0.3-x)Ni_(2) compounds has been investigated.The targeted compounds were synthesized through induction melting and processed heat treatment at 700 and 900℃,respectively.Phase occurrence and structural properties were studied by X-ray powder diffraction(XRD).The global compositions and phase compositions have been determined by inductively coupled plasma-optical emission spectrometer(ICP-AES) and electron probe microanalysis(EPMA) respectively.展开更多
SrCe_(0.9)Yb_(0.1)O_(3-α)ceramic samples were obtained by dry pressing and sintering of powders prepared by solid reaction method.X-ray diffraction(XRD)and the field-emission scanning microscope(SEM)were used for pha...SrCe_(0.9)Yb_(0.1)O_(3-α)ceramic samples were obtained by dry pressing and sintering of powders prepared by solid reaction method.X-ray diffraction(XRD)and the field-emission scanning microscope(SEM)were used for phase and microstructure analysis of samples.XRD results showed that the ceramics sintered in the air were pure perovskite structures.SEM results revealed that the average grain size of ceramics increased from 2 to 10μm when the sinteringtemperature increased from 1400 to 1500℃.展开更多
High density and safe storage of hydrogen are the preconditions for the large-scale application of hydrogen energy.Herein,the hydrogen storage properties of Ti_(0.6)Zr_(0.4)Cr_(0.6)Mn_(1.4) alloys are systematically s...High density and safe storage of hydrogen are the preconditions for the large-scale application of hydrogen energy.Herein,the hydrogen storage properties of Ti_(0.6)Zr_(0.4)Cr_(0.6)Mn_(1.4) alloys are systematically studied by introducing Y element instead of Ti element through vacuum arc melting.After the partial substitution of Y,a second phase of rare earth oxide is added in addition to the main suction hydrogen phase,C14 Laves phase.Thanks to the unique properties of rare earth elements,the partial substitution of Y can not only improve the activation properties and plateau pressure of the alloys,but also increase the effective hydrogen storage capacity of the alloys.The comprehensive properties of hydrogen storage alloys are improved by multidimensional regulation of rare earth elements.Among them,Ti_(0.552)Y_(0.048)Zr_(0.4)Cr_(0.6)Mn_(1.4) has the best comprehensive performance.The alloy can absorb hydrogen without activation at room temperature and 5 MPa,with a maximum hydrogen storage capacity of 1.98 wt.%.At the same time,it reduces the stability of the hydride and the enthalpy change value,making it easier to release hydrogen.Through theoretical analysis and first-principle simulation,the results show that the substitution of Y element reduces the migration energy barrier of hydrogen and the structural stability of the system,which is conducive to hydrogen evolution.The alloy has superior durability compared to the original alloy,and the capacity retention rate was 96.79%after 100 hydrogen absorption/desorption cycles.展开更多
Solar selective absorbing coatings directly harvest solar energy in the form of heat.The higher temperatures are required to drive higher power-cycle efficiencies in favor of lower costs of energy.According to differe...Solar selective absorbing coatings directly harvest solar energy in the form of heat.The higher temperatures are required to drive higher power-cycle efficiencies in favor of lower costs of energy.According to different dielectrics,high temperature coatings can mainly be divided to double cermet solar selective coatings,transition metal nitride multilayer coatings and transition metal oxide multilayer coatings.This paper assesses the photothermal conversion efficiency and thermal stability,and discusses the challenges and strategies of improving both thermal and optical properties.Double cermet layers can stabilize nanocrystalline structures by alloying,while transition metal nitride/oxide layers generally choose the reliable materials with superior mechanical properties and thermal stability.The purpose of this review is to get the optimized systems,and propose further research directions at higher temperature,such as all-ceramic absorbing coatings.展开更多
A tritium permeation barrier is required in fusion blankets for the reduction of fuel loss and radiological hazard.In this study,an Al2O3/Y2O3 composite coating was prepared on 316 L stainless steel by radiofrequency ...A tritium permeation barrier is required in fusion blankets for the reduction of fuel loss and radiological hazard.In this study,an Al2O3/Y2O3 composite coating was prepared on 316 L stainless steel by radiofrequency magnetron sputtering in order to improve the tritium permeation resistance.The microstructure and the phase composition of the Al2O3/Y2O3 composite coating are observed by scanning electron microscopy,transmission electron microscopy and grazing incidence X-ray diffraction.Moreover,Auger electron spectroscopy was used to characterize the depth profiles of Al,Y and O elements.The results clearly indicate that the Al2O3/Y2O3 composite coating is fully dense and the total thickness is approximately 340 nm.The Al2O3/Y2O3 coating consists of an amorphous Al2O3 and the cubic Y2O3,in which Al,Y and O elements are homogeneously distributed in the vertical base direction.Furthermore,the deuterium permeation property of the Al2O3/Y2O3 composite coating was measured by the gas phase permeation method.The results show that the introduction of an interface and the existence of a tiny amount of micro-defects improve the deuterium resistance of the Al2O3/Y2O3 coating,and its deuterium permeation reduction factor is 536-750 at 873-973 K.Therefore,it is concluded that the Al2O3/Y2O3 co mposite coating as deuterium permeation barrier can significa ntly enha nce the deuterium permeation resistance property.展开更多
The Al_(2)O_(3)/Y_(2)O_(3) composite coating with a total thickness of 320 nm was prepared by radio-frequency magnetron sputtering.The annealing treatments in three different atmosphere,Ar gas,H;and vacuum,were perfor...The Al_(2)O_(3)/Y_(2)O_(3) composite coating with a total thickness of 320 nm was prepared by radio-frequency magnetron sputtering.The annealing treatments in three different atmosphere,Ar gas,H;and vacuum,were performed in order to study the influence of microstructure on the deuterium resistance of the coating.展开更多
Single-atom catalysts(SACs)reveal great potential for application in catalysis due to their fully exposed active sites.In general,single atoms(SAs)and the coordination substrates need to have strong interactions or ch...Single-atom catalysts(SACs)reveal great potential for application in catalysis due to their fully exposed active sites.In general,single atoms(SAs)and the coordination substrates need to have strong interactions or charge transfer to ensure the atomic dispersion,which requires the selection of a suitable substrate to stabilize the target atoms.Recent studies have demonstrated that amorphous materials with abundant defects and coordinatively unsaturated sites can be used as substrates for more efficient capturing SAs,further enhancing the catalytic performance.In this review,we discuss recent research progress of SAs loaded on amorphous substrates for enhanced catalytic activity.Firstly,we summarize the commonly used amorphous substrates for stabilizing SAs.Subsequently,we present several advanced applications of amorphous SACs in the field of catalysis,including electrocatalysis and photocatalysis.And then,we also clarify the synergistic mechanism between SAs and amorphous substrate on catalytic process.Finally,we summarize the challenges with our personal views and provide a critical outlook on how amorphous SACs continue to evolve.展开更多
The corrosion resistance of Al0.2CoCrFeNi high-entropy alloy(HEA) film deposited by magnetron sputtering was investigated and compared with that of Al0.2 CoCrFeNi HEA bulk and G115 alloy.The HEA film is composed of fa...The corrosion resistance of Al0.2CoCrFeNi high-entropy alloy(HEA) film deposited by magnetron sputtering was investigated and compared with that of Al0.2 CoCrFeNi HEA bulk and G115 alloy.The HEA film is composed of face-centered cubic with nanoscale grain size.The HE As(film and bulk) exhibit higher electro-chemical corrosion resistance than the G115 alloy in 3.5 wt% NaCl solution.展开更多
The superlattice La-Y-Ni-based hydrogen storage alloys have high discharge capacity and are easy to prepare.However,there is still a gap in commercial applications because of the severe corrosion of the alloys in elec...The superlattice La-Y-Ni-based hydrogen storage alloys have high discharge capacity and are easy to prepare.However,there is still a gap in commercial applications because of the severe corrosion of the alloys in electrolyte and poor high-rate dischargeability(HRD).Therefore,(LaSmY)(NiMnAl)_(3.5) alloy was prepared by magnetic levitation induction melting,and then the alloy was coated with different contents(0.1 wt%-1.0 wt%) of nano-carbons by low-temperature sintering with sucrose as the carbon source in this work.The results show that the cyclic stability and HRD of the alloy first increase and then decrease with the increase of carbon contents.The kinetic results show that the electrocatalytic activity and conductivity of the alloy electrodes can be enhanced by carbon coating.The electrochemical properties of the alloy are the best when the carbon coating content is 0.3 wt%.Compared with the uncoated alloy,the maximum discharge capacity(C_(max)) improves from 354.5 to 359.0 mAh/g,the capacity retention rate after 300 cycles(S_(300)) enhances from 73.15% to 80.01%,and the HRD_(1200) of the alloy enhances from 74.39% to 74.39%.展开更多
文摘1.Introduction Hydrogen energy can be stored and transported,which is not only one of its advantages,but also the main bottleneck in its application.Solid hydrogen storage provides an important means of storing hydrogen energy with high density and safety.First,this method can greatly improve the hydrogen storage density.Among the three existing hydrogen storage methods,namely,high-pressure compression,liquefaction,and solidification,solid-state hydrogen storage has the highest volumetric hydrogen storage density.For example,the volumetric hydrogen storage density of MgH2 can reach 106 kg H2 per cubic meter.
基金This work was supported by the National Key R&D Program of China(No.2021YFB4000604)National Science and Technology Major Project(No.2020YFE0204500)+3 种基金Youth Growth Science and Technology Program of Jilin Province(No.20220508001RC)Major Science and Technology Project of Inner Mongolia(No.2021ZD0029)Youth Innovation Promotion Association CAS(Nos.2021225 and 2022225)Independent Research Project of the State Key Laboratory of Rare Earth Resources Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences(No.110000RL86).
文摘Complex hydride LiAlH_(4),as a hydrogen storage material,possesses high theoretical hydrogen storage capacity(10.5 wt.%).However,highly efficient additives are urgently required to modify its thermal stability and sluggish kinetics.Some additives exhibit unique morphology-dependent characteristics.Herein,the efficient rare earth oxide nano-CeO_(2)additives with different morphologies(nanoparticles,nanocubes,and nanorods)are prepared by the hydrothermal method,and the intrinsic properties are characterized.The three different morphologies of nano-CeO_(2),which are different in the Ce^(3+)content and specific surface area,are added to LiAlH_(4)to improve the dehydrogenation behavior.The LiAlH_(4)-CeO_(2)-nanorod composite exhibits the optimal dehydrogenation behavior,which begins to desorb hydrogen at 76.6℃ with a hydrogen capacity of 7.17 wt.%,and 3.83 wt.%hydrogen is desorbed within 30 min at 140℃.The dehydrogenation process of the composites demonstrates that hydrogen release is facilitated by the in-situ formed CeH_(2).73 and the facile transition between the oxidation states of Ce^(4+)and Ce^(3+).Combined with density functional theory calculations,the addition of nano-CeO_(2)can weaken the Al-H bond and accelerate the decomposition of[AlH_(4)]^(4-)tetrahedron,which is consistent with the reduction of the decomposition activation energy.
基金The authors acknowledged the National Key Research and Development Program of China(No.2021YFB4000604)Key R&D projects of Jilin Provincial Science and Technology Development Plan(Nos.20230201125GX,20230201140GX,and 20200401039GX)+4 种基金Special fund of Scientific and Technological Cooperation Program between Jilin Province and Chinese Academy of Sciences(No.2021SYHZ0045)Jilin Scientific and Technological Development Program(No.20200401039GX)State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization(No.2021H2270)Youth Innovation Promotion Association CAS(No.2021225)Youth Growth Science and Technology Program of Jilin Province(No.20220508001RC).
文摘Aluminum hydride is a promising chemical hydrogen storage material that can achieve dehydrogenation under mild conditions as well as high hydrogen storage capacity.However,designing an efficient and cost-effective catalyst,especially a synergistic catalyst,for realizing low-temperature and high-efficiency hydrogen supply remains challenging.In this study,the heterojunction synergistic catalyst of Ti_(3)C_(2)supported PrF_(3)nanosheets considerably improved the dehydrogenation kinetics of AlH_(3)at low temperatures and maintained a high hydrogen storage capacity.In the synergistic catalyst,Pr produced a synergistic coupling interaction through its unique electronic structure.The sandwich structure with close contact between the two phases enhanced the interaction between species and the synergistic effect.The initial dehydrogenation temperature of the composite is reduced to 70.2℃,and the dehydrogenation capacity is 8.6 wt.%at 120℃ in 90 min under the kinetic test,which reached 93%of the theoretical hydrogen storage capacity.The catalyst considerably reduced the activation energy of the dehydrogenation reaction.Furthermore,the multielectron pairs on the surface of the catalyst promoted electron transfer and accelerated the reaction.
基金financially supported by GRINM Science and Technology Innovation Fund (Nos. 2020DY0109 and 57222001)the Opening Project Fund of Materials Service Safety Assessment Facilities (No. MSAF-2021-001)Guangdong High Level Innovation Research Institute (No. 2021B0909050001)。
文摘Silicon is one of the most promising anode materials for lithium-ion batteries(LIBs), but it suffers from pulverization and hence poor cycling stability due to the large volume variation during lithiation/delithiation. The core-shell structure is considered as an effective strategy to solve the expansion problem of silicon-based anodes. In this paper, the double-shell structured Si@SnO_(2) @C nanocomposite with nano-silicon as the core and SnO_(2) , C as the shells is synthesized by a facile hydrothermal method.Structural characterization shows that Si@SnO_(2) @C nanocomposite is composed of crystalline Si, crystalline SnO_(2) and amorphous C, and the contents of them are 42.1wt%, 37.8 wt% and 20.1 wt%, respectively. Transmission electron microscope(TEM) observations confirm the double-shell structure of Si@SnO_(2) @C nanocomposite, and the thicknesses of the SnO_(2) and C layers are 20 and 7 nm. The Si@SnO_(2) @C electrode exhibits a high initial discharge capacity of 2777 mAh·g^(-1)at 100 mA·g^(-1)and an excellent rate capability of 340 mAh·g^(-1)at 1500 mA·g^(-1). The outstanding capacity retention is 50.2% after 300 cycles over a potential of 0.01 to 2.00 V(vs. Li/Li+) at 500 mA·g^(-1). The resistance of solid electrolyte interphase(SEI) film(Rf) and charge transfer resistance(Rct) of Si@SnO_(2) @C are 7.68and 0.82 Ω, which are relatively smaller than those of Si@C(21.64 and 2.62 Ω). It is obviously seen that the SnO_(2) shell can reduce the charge transfer resistance, leading to high ion and electron transport efficiency in the Si@SnO_(2) @C electrode. The incorporation of SnO_(2) shell is attributed to the enhanced rate capability and cycling performance of Si@SnO_(2) @C nanocomposite.
基金financially supported by the National Key R&D Program of China (No.2019YFE0103600)。
文摘The effect of heat treatment on phase occurrence,crystal structures and hydrogen sorption properties of Y_(0.5)La_(0.2)Mg_(0.3-x)Ni_(2) compounds has been investigated.The targeted compounds were synthesized through induction melting and processed heat treatment at 700 and 900℃,respectively.Phase occurrence and structural properties were studied by X-ray powder diffraction(XRD).The global compositions and phase compositions have been determined by inductively coupled plasma-optical emission spectrometer(ICP-AES) and electron probe microanalysis(EPMA) respectively.
基金financially supported by the National Key Research and Development Program of China(Nos.2016YFB0600103,2016YFB0600102-5)the National natural Science Foundation of China(No.51671034)。
文摘SrCe_(0.9)Yb_(0.1)O_(3-α)ceramic samples were obtained by dry pressing and sintering of powders prepared by solid reaction method.X-ray diffraction(XRD)and the field-emission scanning microscope(SEM)were used for phase and microstructure analysis of samples.XRD results showed that the ceramics sintered in the air were pure perovskite structures.SEM results revealed that the average grain size of ceramics increased from 2 to 10μm when the sinteringtemperature increased from 1400 to 1500℃.
基金supported by the Major Science and Technology Project of Inner Mongolia(No.2021ZD0029)the National Natural Science Foundation of China(No.52301295)+5 种基金Key R&D projects of Jilin Provincial Science and Technology Development Plan(No.20230201125GX)Special fund of Scientific and Technological Cooperation Program between Jilin Province and Chinese Academy of Sciences(No.2023SYHZ0031)the Youth Innovation Promotion Association CAS(No.2022225)Guangdong Provincial University Innovation Team Project(No.2023KCXTD038)the State Key Laboratory of Rare Earth Resources Utilization(No.110000RL86)Changchun Institute of Applied Chemistry.
文摘High density and safe storage of hydrogen are the preconditions for the large-scale application of hydrogen energy.Herein,the hydrogen storage properties of Ti_(0.6)Zr_(0.4)Cr_(0.6)Mn_(1.4) alloys are systematically studied by introducing Y element instead of Ti element through vacuum arc melting.After the partial substitution of Y,a second phase of rare earth oxide is added in addition to the main suction hydrogen phase,C14 Laves phase.Thanks to the unique properties of rare earth elements,the partial substitution of Y can not only improve the activation properties and plateau pressure of the alloys,but also increase the effective hydrogen storage capacity of the alloys.The comprehensive properties of hydrogen storage alloys are improved by multidimensional regulation of rare earth elements.Among them,Ti_(0.552)Y_(0.048)Zr_(0.4)Cr_(0.6)Mn_(1.4) has the best comprehensive performance.The alloy can absorb hydrogen without activation at room temperature and 5 MPa,with a maximum hydrogen storage capacity of 1.98 wt.%.At the same time,it reduces the stability of the hydride and the enthalpy change value,making it easier to release hydrogen.Through theoretical analysis and first-principle simulation,the results show that the substitution of Y element reduces the migration energy barrier of hydrogen and the structural stability of the system,which is conducive to hydrogen evolution.The alloy has superior durability compared to the original alloy,and the capacity retention rate was 96.79%after 100 hydrogen absorption/desorption cycles.
基金supported by National Natural Science Foundation of China(Grant no.51801178).
文摘Solar selective absorbing coatings directly harvest solar energy in the form of heat.The higher temperatures are required to drive higher power-cycle efficiencies in favor of lower costs of energy.According to different dielectrics,high temperature coatings can mainly be divided to double cermet solar selective coatings,transition metal nitride multilayer coatings and transition metal oxide multilayer coatings.This paper assesses the photothermal conversion efficiency and thermal stability,and discusses the challenges and strategies of improving both thermal and optical properties.Double cermet layers can stabilize nanocrystalline structures by alloying,while transition metal nitride/oxide layers generally choose the reliable materials with superior mechanical properties and thermal stability.The purpose of this review is to get the optimized systems,and propose further research directions at higher temperature,such as all-ceramic absorbing coatings.
基金Project supported by the National Natural Science Foundation of China(51671034)。
文摘A tritium permeation barrier is required in fusion blankets for the reduction of fuel loss and radiological hazard.In this study,an Al2O3/Y2O3 composite coating was prepared on 316 L stainless steel by radiofrequency magnetron sputtering in order to improve the tritium permeation resistance.The microstructure and the phase composition of the Al2O3/Y2O3 composite coating are observed by scanning electron microscopy,transmission electron microscopy and grazing incidence X-ray diffraction.Moreover,Auger electron spectroscopy was used to characterize the depth profiles of Al,Y and O elements.The results clearly indicate that the Al2O3/Y2O3 composite coating is fully dense and the total thickness is approximately 340 nm.The Al2O3/Y2O3 coating consists of an amorphous Al2O3 and the cubic Y2O3,in which Al,Y and O elements are homogeneously distributed in the vertical base direction.Furthermore,the deuterium permeation property of the Al2O3/Y2O3 composite coating was measured by the gas phase permeation method.The results show that the introduction of an interface and the existence of a tiny amount of micro-defects improve the deuterium resistance of the Al2O3/Y2O3 coating,and its deuterium permeation reduction factor is 536-750 at 873-973 K.Therefore,it is concluded that the Al2O3/Y2O3 co mposite coating as deuterium permeation barrier can significa ntly enha nce the deuterium permeation resistance property.
基金financially supported by the National Key Research and Development Program of China(Nos.2016YFB0600102 and 2016YFB0600103)the National Natural Science Foundation of China(No.51671034)。
文摘The Al_(2)O_(3)/Y_(2)O_(3) composite coating with a total thickness of 320 nm was prepared by radio-frequency magnetron sputtering.The annealing treatments in three different atmosphere,Ar gas,H;and vacuum,were performed in order to study the influence of microstructure on the deuterium resistance of the coating.
基金supported by the National Natural Science Foundation of China(No.22305051)the National Key Research and Development Project(No.2023YFF0611100)+3 种基金the Fundamental Research Funds for the Central Universities(No.265QZ2022002)the Natural Science Foundation of Henan Province(No.232300421104)the Funding of GRIMAT Engineering Institute(No.5222201)the National Key R&D Program of China(No.2021YFB4001301-2)。
文摘Single-atom catalysts(SACs)reveal great potential for application in catalysis due to their fully exposed active sites.In general,single atoms(SAs)and the coordination substrates need to have strong interactions or charge transfer to ensure the atomic dispersion,which requires the selection of a suitable substrate to stabilize the target atoms.Recent studies have demonstrated that amorphous materials with abundant defects and coordinatively unsaturated sites can be used as substrates for more efficient capturing SAs,further enhancing the catalytic performance.In this review,we discuss recent research progress of SAs loaded on amorphous substrates for enhanced catalytic activity.Firstly,we summarize the commonly used amorphous substrates for stabilizing SAs.Subsequently,we present several advanced applications of amorphous SACs in the field of catalysis,including electrocatalysis and photocatalysis.And then,we also clarify the synergistic mechanism between SAs and amorphous substrate on catalytic process.Finally,we summarize the challenges with our personal views and provide a critical outlook on how amorphous SACs continue to evolve.
基金financially supported by the National Key Research and Development Program of China (Nos. 2016YFB0600103 and 2016YFB0600102)
文摘The corrosion resistance of Al0.2CoCrFeNi high-entropy alloy(HEA) film deposited by magnetron sputtering was investigated and compared with that of Al0.2 CoCrFeNi HEA bulk and G115 alloy.The HEA film is composed of face-centered cubic with nanoscale grain size.The HE As(film and bulk) exhibit higher electro-chemical corrosion resistance than the G115 alloy in 3.5 wt% NaCl solution.
基金The financial supports provided by the National Key R&D Program of China (2019YFE0103600)。
文摘The superlattice La-Y-Ni-based hydrogen storage alloys have high discharge capacity and are easy to prepare.However,there is still a gap in commercial applications because of the severe corrosion of the alloys in electrolyte and poor high-rate dischargeability(HRD).Therefore,(LaSmY)(NiMnAl)_(3.5) alloy was prepared by magnetic levitation induction melting,and then the alloy was coated with different contents(0.1 wt%-1.0 wt%) of nano-carbons by low-temperature sintering with sucrose as the carbon source in this work.The results show that the cyclic stability and HRD of the alloy first increase and then decrease with the increase of carbon contents.The kinetic results show that the electrocatalytic activity and conductivity of the alloy electrodes can be enhanced by carbon coating.The electrochemical properties of the alloy are the best when the carbon coating content is 0.3 wt%.Compared with the uncoated alloy,the maximum discharge capacity(C_(max)) improves from 354.5 to 359.0 mAh/g,the capacity retention rate after 300 cycles(S_(300)) enhances from 73.15% to 80.01%,and the HRD_(1200) of the alloy enhances from 74.39% to 74.39%.
