The electrochemical carbon dioxide reduction reaction(eCO_(2)RR),which converts CO_(2)into various hydrocarbons or alcohols,has been extensively researched because it promises a sustainable energy economy.However,only...The electrochemical carbon dioxide reduction reaction(eCO_(2)RR),which converts CO_(2)into various hydrocarbons or alcohols,has been extensively researched because it promises a sustainable energy economy.However,only copper(Cu)can currently achieve stable and efficient hydrocarbon conversion in the eCO_(2)RR.Therefore,understanding the catalytic mechanisms and summarizing the research progress on synthesis strategies of Cu catalysts are essential for the eCO_(2)RR.This paper reviews Cu catalysts with different surface states of Cu catalysts:oxide-derived Cu,Cu nanoparticles,Cu single atoms,and Cu nanoclusters.It then reviews the development and progress of different Cu-catalyst preparation methods in recent years,focusing on the activity and selectivity of materials.Besides revealing the tendencies of catalytic selection and deep reactive mechanisms of Cu catalysts with four different surface states,this review can guide the subsequent construction of catalysts and provides an understanding of catalytic mechanisms.展开更多
Transcription factors regulating crop uptake and translocation of the micronutrient Cu have not been identified.We isolated a novel R2R3-MYB transcription factor,OsMYB84,and showed that it was a positive regulator inv...Transcription factors regulating crop uptake and translocation of the micronutrient Cu have not been identified.We isolated a novel R2R3-MYB transcription factor,OsMYB84,and showed that it was a positive regulator involved in uptake and transport of Cu via activation of OsCOPT2 and OsHMA expression.OsMYB84 was highly expressed in roots and anthers and induced by Cu.Overexpression of OsMYB84 promoted uptake and root-to-shoot translocation of Cu in rice,facilitated Cu distribution into grain and increased grain yield.In contrast,mutation of OsMYB84 reduced Cu concentration in xylem sap.OsMYB84 bound to the promoter region of OsCOPT2 and OsHMA5 and upregulated their expression.OsCOPT2 mutants showed reduced uptake of Cu and OsHMA5 overexpression lines showed increased root-to-shoot translocation of Cu.展开更多
The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol selectivity.However,there was still no experimental confirm...The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol selectivity.However,there was still no experimental confirmation if copper could be a good promoter for In_(2)O_(3).Herein,the Cu promoted In_(2)O_(3) catalyst was prepared using a deposition-precipitation method.Such prepared Cu/In_(2)O_(3) catalyst shows significantly higher CO_(2) conversion and space time yield(STY)of methanol,compared to the un-promoted In_(2)O_(3) catalyst.The loading of Cu facilitates the activation of both H_(2) and CO_(2) with the interface between the Cu cluster and defective In_(2)O_(3) as the active site.The Cu/In_(2)O_(3) catalyst takes the CO hydrogenation pathway for methanol synthesis from CO_(2) hydrogenation.It exhibits a unique size effect on the CO adsorption.At temperatures below 250℃,CO adsorption on Cu/In_(2)O_(3) is stronger than that on In_(2)O_(3),causing higher methanol selectivity.With increasing temperatu res,the Cu catalyst aggregates,which leads to the formation of weak CO adsorption site and causes a decrease in the methanol selectivity.Compared with other metal promoted In_(2)O_(3) catalysts,it can be concluded that the catalyst with stronger CO adsorption possesses higher methanol selectivity.展开更多
Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a ch...Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.展开更多
A simple method was proposed to activate alkaline Cu(OH)_(2)with an acidic ionomer,Nafion,to regulate its surface microenvironment,including hydrophobicity and local basicity.In particular,the direct complete neutrali...A simple method was proposed to activate alkaline Cu(OH)_(2)with an acidic ionomer,Nafion,to regulate its surface microenvironment,including hydrophobicity and local basicity.In particular,the direct complete neutralization reaction between Cu(OH)_(2)and Nafion in aqueous solution induces the exposing of vast anions which can exclude the in-situ-formed hydroxides and raise the local basicity.Remarkably,the optimal Nafionactivated Cu(OH)_(2)-derived Cu can efficiently suppress the hydrogen evolution reaction(HER)and improve the selectivity for multi-carbon products in the CO_(2)electroreduction reaction(eCO_(2)RR).The H2 Faradaic efficiency(FE)decreased to 11%at a current density of 300 mA/cm2(−0.76 V vs.RHE)in a flow cell,while the bare one with H2 had an FE of 40%.The total eCO_(2)RR FE reaches as high as 83%,along with an evidently increased C2H4 FE of 44%as compared with the bare one(24%),and good stability(8000 s),surpassing that of most of the reported Cu(OH)_(2)-derived Cu.The experimental and theoretical results both show that the strong hydrophobicity and high local basicity jointly boosted the eCO_(2)RR as acquired by felicitously introducing ionomer on the Cu(OH)_(2)-derived Cu surface.展开更多
High energy density Li-CO_(2)batteries have attracted much attention owing to the"two birds with one stone"feature in fixing greenhouse gas CO_(2)and providing renewable energy.However,poor reversibility of ...High energy density Li-CO_(2)batteries have attracted much attention owing to the"two birds with one stone"feature in fixing greenhouse gas CO_(2)and providing renewable energy.However,poor reversibility of the discharge product Li_(2)CO_(3)is one of the main problems that limit its application,resulting in poor cycling stability and severe polarization.Herein,copper indium sulfide(CIS),a semiconducting non-precious metal sulfide,is fabricated as cathode catalysts for high-performance Li-CO_(2)batteries.Combined with the synergistic effect of bimetallic valence bonding and coordinated electron transfer,Li-CO_(2)batteries using CIS cathodes exhibit high full specific discharge capacity,excellent rate capability and cycle stability,namely it delivers a high specific full discharge capacity of 8878μAh cm^(-2),runs steadily from 10 to 100μA cm^(-2),and performs a stable long-term cycling behavior(>1050 h)under a high energy efficiency of 84%and a low charge voltage of approximately 3.4 V at 20μA cm^(-2)within 100μAh cm^(-2).In addition,a flexible Li-CO_(2)pouch cell is constructed to reveal the potential of employing CIS to fabricate flexible high energy storage devices in practical applications.This work shows a promising development pathway toward next-generation sustainable energy storage devices.展开更多
The Jiama porphyry copper deposit in Tibet is one of the proven supergiant copper deposits in the Qinghai-Tibet Plateau at present,with the reserves of geological resources equivalent to nearly 20×10^(6) t.Howeve...The Jiama porphyry copper deposit in Tibet is one of the proven supergiant copper deposits in the Qinghai-Tibet Plateau at present,with the reserves of geological resources equivalent to nearly 20×10^(6) t.However,it features wavy and steep terrain,leading to extremely difficult field operation and heavy interference.This study attempts to determine the effects of the tensor controlled-source audiomagnetotellurics(CSAMT)with high-power orthogonal signal sources(also referred to as the high-power tensor CSAMT)when it is applied to the deep geophysical exploration in plateaus with complex terrain and mining areas with strong interference.The test results show that the high current provided by the highpower tensor CSAMT not only greatly improved the signal-to-noise ratio but also guaranteed that effective signals were received in the case of a long transmitter-receiver distance.Meanwhile,the tensor data better described the anisotropy of deep geologic bodies.In addition,the tests also show that when the transmitting current reaches 60 A,it is still guaranteed that strong enough signals can be received in the case of the transmitter-receiver distance of about 25 km,sounding curves show no near field effect,and effective exploration depth can reach 3 km.The 2D inversion results are roughly consistent with drilling results,indicating that the high-power tensor CSAMT can be used to achieve nearly actual characteristics of underground electrical structures.Therefore,this method has great potential for application in deep geophysical exploration in plateaus and mining areas with complex terrain and strong interference,respectively.This study not only serves as important guidance on the prospecting in the Qinghai-Tibet Plateau but also can be used as positive references for deep mineral exploration in other areas.展开更多
In this study,the benign target double terpyridine parts based amphiphilic ionic molecules(AIMs 1,2)and the reference single terpyridine segment included AIMs(AIMs 3,4)were synthesized through a multi-step method,and ...In this study,the benign target double terpyridine parts based amphiphilic ionic molecules(AIMs 1,2)and the reference single terpyridine segment included AIMs(AIMs 3,4)were synthesized through a multi-step method,and the molecular structures were fully characterized.The excellent anticorrosion of the target AIMs for copper surface in H_(2)SO_(4) solution was demonstrated by the electrochemistry analysis,which was more superior over those of the reference AIMs.The standard adsorption free energy changes of the target AIMs calculated by the adsorption isotherms were lower than -40 kJ·mol^(-1),suggesting an intensified chemical adsorption on metal surface.The molecular modeling and molecular dynamic computation of the studied AIMs were performed,demonstrating that the target AIMs exhibited lower highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps and greater adsorption energies than the reference ones.The chemical adsorption of the AIMs on metal surface was revealed by various spectroscopic methods including scanning electron microscopy,atomic force microscopy,Fourier transform infrared spectroscopy,attenuated total reflection infrared spectroscopy,Raman and X-ray diffraction.展开更多
B_(2)O_(3)-Zn O-SiO_(2)(BZS)glass containing Cu O with excellent acid resistance,wetting properties,and high-temperature sintering density was prepared by high temperature melting method and then applied in copper ter...B_(2)O_(3)-Zn O-SiO_(2)(BZS)glass containing Cu O with excellent acid resistance,wetting properties,and high-temperature sintering density was prepared by high temperature melting method and then applied in copper terminal electrode for multilayer ceramic capacitors(MLCC)applications.The structure and property characterization of B_(2)O_(3)-Zn O-SiO_(2)glass,including X-ray diffraction,FTIR,scanning electron microscopy,high-temperature microscopy,and differential scanning calorimetry,indicated that the addition of CuO improved the glass’s acid resistance and glass-forming ability.The wettability and acid resistance of this glass were found to be excellent when CuO content was 1.50 wt%.Compared to BZS glass,the CuO-added glass exhibited excellent wettability to copper powder and corrosion resistance to the plating solution.The sintered copper electrode films prepared using the glass with CuO addition had better densification and lower sintering temperature of 750℃.Further analysis of the sintering mechanism reveals that the flowability and wettability of the glass significantly impact the sintering densification of the copper terminal electrodes.展开更多
The horizontal continuous casting process,the initial step in TP2 copper tubular processing,directly determines the microstructure and properties of copper tubular.However,the process parameters of the continuous cast...The horizontal continuous casting process,the initial step in TP2 copper tubular processing,directly determines the microstructure and properties of copper tubular.However,the process parameters of the continuous casting characterize time variation,multiple disturbances and strong coupling.As a consequence,their influence on a casting billet is difficult to be determined.Due to the above issues,the common factor and special factor analysis of the factor analysis model were used in this study,and the casting experiment and billet metallographic experiment were carried out to diagnose and analyze the reason of the microstructure inhomogeneity.The multiple process parameters were studied and classified using common factor analysis,2 the cast billets with abnormal microstructures were identified by GT^(2) statistics,and the most important factors affecting the microstructural homogeneity were found by special factor analysis.The calculated and experimental results show that the principal parameters influencing the inhomogeneity of solidified microstructure are the primary inlet water pressure and the primary outlet water temperature.According to the consequence of the above investigation,the inhomogeneity of the copper billet microstructure can be effectively improved when the process parameters are controlled and adjusted.展开更多
Electroreduction of carbon dioxide(CO_(2)) into value-added chemicals offers an entrancing approach to main-taining the global carbon cycle and eliminating environmental threats.A key obstacle to achieving long-term a...Electroreduction of carbon dioxide(CO_(2)) into value-added chemicals offers an entrancing approach to main-taining the global carbon cycle and eliminating environmental threats.A key obstacle to achieving long-term and large-scale implementation of electrochemical CO_(2) reduction technology is the lack of active and selective cat-alysts.Copper(Cu)is one of the few candidates that can facilitate C–C coupling to obtain high-energy oxygenates and hydrocarbons beyond carbon monoxide(CO),but it suffers from poor selectivity for products of interest and high overpotentials.Alloying is an effective way to break the linear scaling relations and uniquely manipulate the reactivity and selectivity,which is hard to achieve by using monometallic compositions alone.By alloying Cu with other metals,one could change the catalytic properties of the catalyst by tuning the local electronic structure and modulating the adsorption strength of the reaction intermediates,thus improving the catalytic activity and selectivity.In this review,we focus on the recently developed Cu-based alloy catalysts(including conventional alloys,high-entropy alloys and single-atom alloys)that have been applied in electrocatalytic CO_(2) reduction(ECR).Theoretical calculations and experimental advances in understanding the key rate-limiting and selectivity-determining steps in those alloys are summarized,with a particular focus on identifying binding energy de-scriptors and the dynamic product formation mechanisms.In addition,we outline the opportunities and chal-lenges in the fundamental understanding of ECR by recommending advanced in-situ characterization techniques and standardized electrochemical methods and offer atomic-level design principles for steering the reaction pathways to the desired products.展开更多
基金supported by the Tianjin Science and Technology support key projects (20JCYBJC01420)。
文摘The electrochemical carbon dioxide reduction reaction(eCO_(2)RR),which converts CO_(2)into various hydrocarbons or alcohols,has been extensively researched because it promises a sustainable energy economy.However,only copper(Cu)can currently achieve stable and efficient hydrocarbon conversion in the eCO_(2)RR.Therefore,understanding the catalytic mechanisms and summarizing the research progress on synthesis strategies of Cu catalysts are essential for the eCO_(2)RR.This paper reviews Cu catalysts with different surface states of Cu catalysts:oxide-derived Cu,Cu nanoparticles,Cu single atoms,and Cu nanoclusters.It then reviews the development and progress of different Cu-catalyst preparation methods in recent years,focusing on the activity and selectivity of materials.Besides revealing the tendencies of catalytic selection and deep reactive mechanisms of Cu catalysts with four different surface states,this review can guide the subsequent construction of catalysts and provides an understanding of catalytic mechanisms.
基金supported by grants from the National Key Research and Development Program of China(2021YFD1901203)。
文摘Transcription factors regulating crop uptake and translocation of the micronutrient Cu have not been identified.We isolated a novel R2R3-MYB transcription factor,OsMYB84,and showed that it was a positive regulator involved in uptake and transport of Cu via activation of OsCOPT2 and OsHMA expression.OsMYB84 was highly expressed in roots and anthers and induced by Cu.Overexpression of OsMYB84 promoted uptake and root-to-shoot translocation of Cu in rice,facilitated Cu distribution into grain and increased grain yield.In contrast,mutation of OsMYB84 reduced Cu concentration in xylem sap.OsMYB84 bound to the promoter region of OsCOPT2 and OsHMA5 and upregulated their expression.OsCOPT2 mutants showed reduced uptake of Cu and OsHMA5 overexpression lines showed increased root-to-shoot translocation of Cu.
基金supported by the National Natural Science Foundation of China(22138009)the Fundamental Research Funds for the Central Universities of China。
文摘The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol selectivity.However,there was still no experimental confirmation if copper could be a good promoter for In_(2)O_(3).Herein,the Cu promoted In_(2)O_(3) catalyst was prepared using a deposition-precipitation method.Such prepared Cu/In_(2)O_(3) catalyst shows significantly higher CO_(2) conversion and space time yield(STY)of methanol,compared to the un-promoted In_(2)O_(3) catalyst.The loading of Cu facilitates the activation of both H_(2) and CO_(2) with the interface between the Cu cluster and defective In_(2)O_(3) as the active site.The Cu/In_(2)O_(3) catalyst takes the CO hydrogenation pathway for methanol synthesis from CO_(2) hydrogenation.It exhibits a unique size effect on the CO adsorption.At temperatures below 250℃,CO adsorption on Cu/In_(2)O_(3) is stronger than that on In_(2)O_(3),causing higher methanol selectivity.With increasing temperatu res,the Cu catalyst aggregates,which leads to the formation of weak CO adsorption site and causes a decrease in the methanol selectivity.Compared with other metal promoted In_(2)O_(3) catalysts,it can be concluded that the catalyst with stronger CO adsorption possesses higher methanol selectivity.
基金supported by the National Natural Science Foundation of China(52200123)the Open Project of Key Laboratory of Green Chemical Engineering Process of Ministry of Education(GCP2022007)the Scientific Research and Innovation Team Program of Sichuan University of Science and Engineering(SUSE652A014)。
文摘Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.
基金National Natural Science Foundation of China,Grant/Award Numbers:52201227,21972126,51872209,52072273Zhejiang Provincial Special Support Program for High-level Talents,Grant/Award Number:2019R52042Key Project of Zhejiang Provincial Natural Science Foundation,Grant/Award Number:LZ20B030001。
文摘A simple method was proposed to activate alkaline Cu(OH)_(2)with an acidic ionomer,Nafion,to regulate its surface microenvironment,including hydrophobicity and local basicity.In particular,the direct complete neutralization reaction between Cu(OH)_(2)and Nafion in aqueous solution induces the exposing of vast anions which can exclude the in-situ-formed hydroxides and raise the local basicity.Remarkably,the optimal Nafionactivated Cu(OH)_(2)-derived Cu can efficiently suppress the hydrogen evolution reaction(HER)and improve the selectivity for multi-carbon products in the CO_(2)electroreduction reaction(eCO_(2)RR).The H2 Faradaic efficiency(FE)decreased to 11%at a current density of 300 mA/cm2(−0.76 V vs.RHE)in a flow cell,while the bare one with H2 had an FE of 40%.The total eCO_(2)RR FE reaches as high as 83%,along with an evidently increased C2H4 FE of 44%as compared with the bare one(24%),and good stability(8000 s),surpassing that of most of the reported Cu(OH)_(2)-derived Cu.The experimental and theoretical results both show that the strong hydrophobicity and high local basicity jointly boosted the eCO_(2)RR as acquired by felicitously introducing ionomer on the Cu(OH)_(2)-derived Cu surface.
基金supports by the National Natural Science Foundation of China(No.52072352,21875226,U20A2072,52102320)the Foundation for the Youth S&T Innovation Team of Sichuan Province(2020JDTD0035)+1 种基金Tianfu Rencai Plan,the Science Foundation for Distinguished Young Scholars of Sichuan Province(2017JQ0036)the Chengdu Talent plan,Science and Technology Projects for Administration for Market Regulation of Sichuan Province(SCSJ2020016).
文摘High energy density Li-CO_(2)batteries have attracted much attention owing to the"two birds with one stone"feature in fixing greenhouse gas CO_(2)and providing renewable energy.However,poor reversibility of the discharge product Li_(2)CO_(3)is one of the main problems that limit its application,resulting in poor cycling stability and severe polarization.Herein,copper indium sulfide(CIS),a semiconducting non-precious metal sulfide,is fabricated as cathode catalysts for high-performance Li-CO_(2)batteries.Combined with the synergistic effect of bimetallic valence bonding and coordinated electron transfer,Li-CO_(2)batteries using CIS cathodes exhibit high full specific discharge capacity,excellent rate capability and cycle stability,namely it delivers a high specific full discharge capacity of 8878μAh cm^(-2),runs steadily from 10 to 100μA cm^(-2),and performs a stable long-term cycling behavior(>1050 h)under a high energy efficiency of 84%and a low charge voltage of approximately 3.4 V at 20μA cm^(-2)within 100μAh cm^(-2).In addition,a flexible Li-CO_(2)pouch cell is constructed to reveal the potential of employing CIS to fabricate flexible high energy storage devices in practical applications.This work shows a promising development pathway toward next-generation sustainable energy storage devices.
基金supported by the National Key Research and Development Program of China(2018YFC0604102)the project of China Geological Survey(DD20190015)。
文摘The Jiama porphyry copper deposit in Tibet is one of the proven supergiant copper deposits in the Qinghai-Tibet Plateau at present,with the reserves of geological resources equivalent to nearly 20×10^(6) t.However,it features wavy and steep terrain,leading to extremely difficult field operation and heavy interference.This study attempts to determine the effects of the tensor controlled-source audiomagnetotellurics(CSAMT)with high-power orthogonal signal sources(also referred to as the high-power tensor CSAMT)when it is applied to the deep geophysical exploration in plateaus with complex terrain and mining areas with strong interference.The test results show that the high current provided by the highpower tensor CSAMT not only greatly improved the signal-to-noise ratio but also guaranteed that effective signals were received in the case of a long transmitter-receiver distance.Meanwhile,the tensor data better described the anisotropy of deep geologic bodies.In addition,the tests also show that when the transmitting current reaches 60 A,it is still guaranteed that strong enough signals can be received in the case of the transmitter-receiver distance of about 25 km,sounding curves show no near field effect,and effective exploration depth can reach 3 km.The 2D inversion results are roughly consistent with drilling results,indicating that the high-power tensor CSAMT can be used to achieve nearly actual characteristics of underground electrical structures.Therefore,this method has great potential for application in deep geophysical exploration in plateaus and mining areas with complex terrain and strong interference,respectively.This study not only serves as important guidance on the prospecting in the Qinghai-Tibet Plateau but also can be used as positive references for deep mineral exploration in other areas.
基金the National Natural Science Foundation of China (21376282,21676035,21878029)Chongqing Science and Technology Commission (cstc2018jcyjAX0668)+2 种基金Shandong Province Natural Science Foundation (ZR2020QB18)China Postdoctoral Science Foundation (22012 T50762&2011 M501388)Graduate Student Research Innovation Project,Chongqing University (CYB18046)。
文摘In this study,the benign target double terpyridine parts based amphiphilic ionic molecules(AIMs 1,2)and the reference single terpyridine segment included AIMs(AIMs 3,4)were synthesized through a multi-step method,and the molecular structures were fully characterized.The excellent anticorrosion of the target AIMs for copper surface in H_(2)SO_(4) solution was demonstrated by the electrochemistry analysis,which was more superior over those of the reference AIMs.The standard adsorption free energy changes of the target AIMs calculated by the adsorption isotherms were lower than -40 kJ·mol^(-1),suggesting an intensified chemical adsorption on metal surface.The molecular modeling and molecular dynamic computation of the studied AIMs were performed,demonstrating that the target AIMs exhibited lower highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps and greater adsorption energies than the reference ones.The chemical adsorption of the AIMs on metal surface was revealed by various spectroscopic methods including scanning electron microscopy,atomic force microscopy,Fourier transform infrared spectroscopy,attenuated total reflection infrared spectroscopy,Raman and X-ray diffraction.
基金the National Natural Science Foundation of China(Nos.51372179,51772224)the Open Project Foundation of Guangdong Fenghua Advanced Technology(No.FHR-JS-202011024)。
文摘B_(2)O_(3)-Zn O-SiO_(2)(BZS)glass containing Cu O with excellent acid resistance,wetting properties,and high-temperature sintering density was prepared by high temperature melting method and then applied in copper terminal electrode for multilayer ceramic capacitors(MLCC)applications.The structure and property characterization of B_(2)O_(3)-Zn O-SiO_(2)glass,including X-ray diffraction,FTIR,scanning electron microscopy,high-temperature microscopy,and differential scanning calorimetry,indicated that the addition of CuO improved the glass’s acid resistance and glass-forming ability.The wettability and acid resistance of this glass were found to be excellent when CuO content was 1.50 wt%.Compared to BZS glass,the CuO-added glass exhibited excellent wettability to copper powder and corrosion resistance to the plating solution.The sintered copper electrode films prepared using the glass with CuO addition had better densification and lower sintering temperature of 750℃.Further analysis of the sintering mechanism reveals that the flowability and wettability of the glass significantly impact the sintering densification of the copper terminal electrodes.
基金This work is financially supported by Basic Scientific Project of Liaoning Provincial Department of Education(LJKMZ20220591)Science and Technology Plan Project of Changzhou,China(CQ20220057).
文摘The horizontal continuous casting process,the initial step in TP2 copper tubular processing,directly determines the microstructure and properties of copper tubular.However,the process parameters of the continuous casting characterize time variation,multiple disturbances and strong coupling.As a consequence,their influence on a casting billet is difficult to be determined.Due to the above issues,the common factor and special factor analysis of the factor analysis model were used in this study,and the casting experiment and billet metallographic experiment were carried out to diagnose and analyze the reason of the microstructure inhomogeneity.The multiple process parameters were studied and classified using common factor analysis,2 the cast billets with abnormal microstructures were identified by GT^(2) statistics,and the most important factors affecting the microstructural homogeneity were found by special factor analysis.The calculated and experimental results show that the principal parameters influencing the inhomogeneity of solidified microstructure are the primary inlet water pressure and the primary outlet water temperature.According to the consequence of the above investigation,the inhomogeneity of the copper billet microstructure can be effectively improved when the process parameters are controlled and adjusted.
基金the National Natural Science Foundation of China(NSFC 22102018 and 52171201)the Natural Science Foundation of Sichuan Province(2022NSFSC0194)+6 种基金the Central Government Funds of Guiding Local Scientific and Technological Development for Sichuan Province(2021ZYD0043)the University of Electronic Science and Technology of China for Startup Funding(A1098531023601264)the Hefei National Research Center for Physical Sciences at the Micro-scale(KF2021005)the China Postdoctoral Science Foundation funded project(2022M710601)the University of Elec-tronic Science and Technology of China for Startup Funding(Y030212059003039)the NSFC(22005291 and 22278067)University of Electronic Science and Technology of China for Startup Funding(A1098531023601356).
文摘Electroreduction of carbon dioxide(CO_(2)) into value-added chemicals offers an entrancing approach to main-taining the global carbon cycle and eliminating environmental threats.A key obstacle to achieving long-term and large-scale implementation of electrochemical CO_(2) reduction technology is the lack of active and selective cat-alysts.Copper(Cu)is one of the few candidates that can facilitate C–C coupling to obtain high-energy oxygenates and hydrocarbons beyond carbon monoxide(CO),but it suffers from poor selectivity for products of interest and high overpotentials.Alloying is an effective way to break the linear scaling relations and uniquely manipulate the reactivity and selectivity,which is hard to achieve by using monometallic compositions alone.By alloying Cu with other metals,one could change the catalytic properties of the catalyst by tuning the local electronic structure and modulating the adsorption strength of the reaction intermediates,thus improving the catalytic activity and selectivity.In this review,we focus on the recently developed Cu-based alloy catalysts(including conventional alloys,high-entropy alloys and single-atom alloys)that have been applied in electrocatalytic CO_(2) reduction(ECR).Theoretical calculations and experimental advances in understanding the key rate-limiting and selectivity-determining steps in those alloys are summarized,with a particular focus on identifying binding energy de-scriptors and the dynamic product formation mechanisms.In addition,we outline the opportunities and chal-lenges in the fundamental understanding of ECR by recommending advanced in-situ characterization techniques and standardized electrochemical methods and offer atomic-level design principles for steering the reaction pathways to the desired products.
