The lithium-sulfur battery has attracted enormous attention as being one of the most significant energy storage technologies due to its high energy density and cost-effectiveness.However,the "shuttle effect"...The lithium-sulfur battery has attracted enormous attention as being one of the most significant energy storage technologies due to its high energy density and cost-effectiveness.However,the "shuttle effect" of polysulfide intermediates represents a formidable challenge towards its wide applications.Herein,we have designed and synthesized two-dimensional Cu,Zn and Sn-based multimetallic sulfide nanosheets to construct multi-active sites for the immobilization and entrapment of polysulfides with offering better performance in liquid Li2S6-based lithium-polysulfide batteries.Both experimental measurements and theoretical computations demonstrate that the interfacial multi-active sites of multimetallic sulfides not only accelerate the multi-chained redox reactions of highly diffusible polysulfides,but also strengthen affinities toward polysulfides.By adopting multimetallic sulfide nanosheets as the sulfur host,the liquid Li2 S6-based cell exhibits an impressive rate capability with 1200 mAh/g and retains 580 mAh/g at 0.5 mA/cm^(2) after 1000 cycles.With high sulfur mass loading conditions,the cell with 2.0 mg/cm^(2) sulfur loading delivers a cell capacity of 1068 mAh/g and maintains 480 mAh/g with 0.8 mA/cm^(2) and 500 cycles.This study provides new insights into the multifunctional material design with multi-active sites for elevated lithium-polysulfide batteries.展开更多
Rational construction of active components has been the biggest challenge in preparing efficient bifunctional oxygen electrocatalysts.Herein,electrospinning and chemical vapor deposition(CVD)were employed to embed act...Rational construction of active components has been the biggest challenge in preparing efficient bifunctional oxygen electrocatalysts.Herein,electrospinning and chemical vapor deposition(CVD)were employed to embed active species including FeCo nanoparticles,MNx(M=Fe,Co),and FePx in porous and graphitized carbon nanotubes(CNTs)/carbon nanofiber(CNF).The as-prepared FeCo@CoNx@FePx/C exhibited a half-wave potential as high as 0.86 V in oxygen reduction reaction(ORR)and low oxygen evolution reaction(OER)overpotential of 368 mV at 10 mA·cm^(−2),which are superior to Pt/C(0.83 V)and IrO_(2)(375 mV)respectively.The assembled Zn-air battery(ZAB)showed a high energy efficiency(Edischarge/Echarge)of 65%at 20 mA·cm^(−2)and stabilized for 700 charge-discharge cycles.The spectroscopic and microscopic characterizations evidenced that the outstanding bifunctionality of the electrocatalyst can be ascribed to three main reasons:First,FeCo nanoparticles are rich in MOH/MOOH active sites for OER,and FePx/CNTs constructed with CVD also modulate electronic structure to improve electron transfer;second,both MNx in carbon matrix and FePx/CNTs are highly active towards ORR;third,the CNTs/CNF are highly porous and graphitized,which promotes mass transport and improves electrical conductivity and stability of the electrocatalysts.This work gives important implications on the design of bifunctional electrocatalysts.展开更多
The development of smart coatings with potential for active anticorrosion and self-healing protection of metals is essential for long-term performance of metallic structures in aggressive chemical environments.Present...The development of smart coatings with potential for active anticorrosion and self-healing protection of metals is essential for long-term performance of metallic structures in aggressive chemical environments.Presently,emphasis has been placed on the development of advanced smart coatings for corrosion protection in different applications.Innovative multifunctional coatings with fascinating stimuliresponsive functionalities are considered“smart”.The stimuli-responsive functionalities of these smart coatings when properly harnessed result in a class of coatings with inherent autonomous control of corrosion.Fundamentally,when metals are exposed to aggressive environments,occurrences at the metalsolution interface cause environmental changes.These changes can be controlled when triggers from external environment set off active components of smart coating,thereby enhancing coating’s life and functionality.Common triggers include the availability of moisture,concentration of chloride ion,p H gradient,mechanical damage,impact,fatigue,light,redox activity and temperature.In this review,recent technological trends in active anticorrosion and self-healing coatings as functional routes for metal protection are summarized,stimuli responsiveness and mechanisms of inhibition are discussed,and recent multi-action protective systems are particularly focused on.展开更多
Customized prostheses are normally employed to reconstruct the biomechanics of the pelvis after resection due to tumors or accidents.The objective of this study is to evaluate the biomechanics of the pelvis under diff...Customized prostheses are normally employed to reconstruct the biomechanics of the pelvis after resection due to tumors or accidents.The objective of this study is to evaluate the biomechanics of the pelvis under different daily activities and to establish a functional evaluation methodology for the customized prostheses.For this purposes,finite element model of a healthy pelvis as well as a reconstructed pelvic model after type II+III resection were built for biomechanical study.The biomechanical perfonnance of the healthy and reconstructed pelvic model was studied under routine activities including standing,knee bending,sitting down,standing up,walking,stair descent and stair ascent.Subsequently,the strength and stability of the prosthesis were evaluated under these activities.Results showed that,for the heathy pelvic model,the stresses were mainly concentrated around the upper part of the sacrum and the sacroiliac joint undergoing different activities,and the maximum stress occurred during stair ascent.As for the reconstructed pelvis,the stress distribution and the tendency of the maximum stress variation predicted for the bone part during all the activities were similar to those of the natural pelvic model,which indicated that the load transferring function of the reconstructed pelvis could be restored by the prosthesis.Moreover,the predicted maximum von Mises stress of the screws and prosthesis was below the fatigue strength of the 3D printed Ti-6A1-4V,which indicated the prosthesis can provide a reliable mechanical performance after implantation.展开更多
Currently,single-atom combo catalysts(SACCs)for carbon dioxide reduction reaction(CO_(2)RR)to the formation of HCOOH are still very limited,especially the lanthanide-based SACCs.In this work,the novel SACCs with atomi...Currently,single-atom combo catalysts(SACCs)for carbon dioxide reduction reaction(CO_(2)RR)to the formation of HCOOH are still very limited,especially the lanthanide-based SACCs.In this work,the novel SACCs with atomically dispersed In and Ce active sites were successfully prepared on the nitrogen-doped carbon matrix(InCe/CN).Both aberration-corrected high-angle annular dark-field scanning transmission electron microscopy(AC-HAADF-STEM)images and the extended X-ray absorption fine structure(EXAFS)spectra proved the well-isolated In and Ce atoms.The as-prepared InCe/CN shows a high Faradaic efficiency(FE)(77%)and current density of HCOOH formation(j_(HCOOH))at-1.35 V vs.reversible hydrogen electrode(RHE),much higher than the single atom catalysts.Theoretical calculations have indicated that the introduced Ce single atom sites not only significantly promote electron transfer but also optimize the In-5p orbitals towards higher selectivity towards the HCOOH formation.This work innovatively extends the design of SACCs towards the main group and Ln metals for more applications.展开更多
开发高效且性能稳定的氧析出(OER)、氧还原(ORR)和氢析出(HER)三功能催化剂是制备能源存储与转换设备的关键.本文使用一步磷化法,在氮磷共掺杂碳基上制备了Fe Co金属合金/磷化物催化剂(Fe Co-P/PNC).该催化剂显示了良好的ORR性能,展现了...开发高效且性能稳定的氧析出(OER)、氧还原(ORR)和氢析出(HER)三功能催化剂是制备能源存储与转换设备的关键.本文使用一步磷化法,在氮磷共掺杂碳基上制备了Fe Co金属合金/磷化物催化剂(Fe Co-P/PNC).该催化剂显示了良好的ORR性能,展现了0.86 V (vs.RHE,相对于可逆氢电极)的半波电位;在OER和HER反应中,催化剂在10 m A cm^(-2)的电流密度下的过电位分别为350和158 m V.密度泛函理论计算表明,磷在Fe Co磷化物和碳基体中皆起主导作用,使得该催化剂同时具有良好的ORR、OER和HER功能.以Fe Co-P/PNC为空气阴极组装的水系电池和柔性锌-空气电池的峰值功率密度分别为195.1和90.8 m W cm^(-2),且两种电池均具有优异的充放电性能、长寿命和高柔性.此外,自供能的整体水分解系统表现出较低的(1.71 V)工作电压以驱动10 m A cm^(-2)的电流密度,进一步证实了该催化剂出色的多功能性.展开更多
基金supported by the Start-up Foundation of Nanjing Tech Universitythe National Natural Science Foundation of China (61904080, 61801210, 91833302)+3 种基金the Natural Science Foundation of Jiangsu Province (BK20190670, BK20180686)the Natural Science Foundation of Colleges and Universities in Jiangsu Province (19KJB530008)the Innovation Scientists and Technicians Team Construction Projects of Henan Province (CXTD2017002)the funding for “Distinguished professors” and “High-level talents in six industries” of Jiangsu Province and Technology Innovation Project for Overseas Scholar in Nanjing。
文摘The lithium-sulfur battery has attracted enormous attention as being one of the most significant energy storage technologies due to its high energy density and cost-effectiveness.However,the "shuttle effect" of polysulfide intermediates represents a formidable challenge towards its wide applications.Herein,we have designed and synthesized two-dimensional Cu,Zn and Sn-based multimetallic sulfide nanosheets to construct multi-active sites for the immobilization and entrapment of polysulfides with offering better performance in liquid Li2S6-based lithium-polysulfide batteries.Both experimental measurements and theoretical computations demonstrate that the interfacial multi-active sites of multimetallic sulfides not only accelerate the multi-chained redox reactions of highly diffusible polysulfides,but also strengthen affinities toward polysulfides.By adopting multimetallic sulfide nanosheets as the sulfur host,the liquid Li2 S6-based cell exhibits an impressive rate capability with 1200 mAh/g and retains 580 mAh/g at 0.5 mA/cm^(2) after 1000 cycles.With high sulfur mass loading conditions,the cell with 2.0 mg/cm^(2) sulfur loading delivers a cell capacity of 1068 mAh/g and maintains 480 mAh/g with 0.8 mA/cm^(2) and 500 cycles.This study provides new insights into the multifunctional material design with multi-active sites for elevated lithium-polysulfide batteries.
基金the grants from the National Natural Science Foundation of China(No.22004085)Regional Joint Fund of Guangdong Province(No.2019A1515111054).
文摘Rational construction of active components has been the biggest challenge in preparing efficient bifunctional oxygen electrocatalysts.Herein,electrospinning and chemical vapor deposition(CVD)were employed to embed active species including FeCo nanoparticles,MNx(M=Fe,Co),and FePx in porous and graphitized carbon nanotubes(CNTs)/carbon nanofiber(CNF).The as-prepared FeCo@CoNx@FePx/C exhibited a half-wave potential as high as 0.86 V in oxygen reduction reaction(ORR)and low oxygen evolution reaction(OER)overpotential of 368 mV at 10 mA·cm^(−2),which are superior to Pt/C(0.83 V)and IrO_(2)(375 mV)respectively.The assembled Zn-air battery(ZAB)showed a high energy efficiency(Edischarge/Echarge)of 65%at 20 mA·cm^(−2)and stabilized for 700 charge-discharge cycles.The spectroscopic and microscopic characterizations evidenced that the outstanding bifunctionality of the electrocatalyst can be ascribed to three main reasons:First,FeCo nanoparticles are rich in MOH/MOOH active sites for OER,and FePx/CNTs constructed with CVD also modulate electronic structure to improve electron transfer;second,both MNx in carbon matrix and FePx/CNTs are highly active towards ORR;third,the CNTs/CNF are highly porous and graphitized,which promotes mass transport and improves electrical conductivity and stability of the electrocatalysts.This work gives important implications on the design of bifunctional electrocatalysts.
基金financial support from the National Natural Science Foundation of China(Nos.52171089 and 51571202)Ling Chuang Research Project of China National Nuclear Corporation。
文摘The development of smart coatings with potential for active anticorrosion and self-healing protection of metals is essential for long-term performance of metallic structures in aggressive chemical environments.Presently,emphasis has been placed on the development of advanced smart coatings for corrosion protection in different applications.Innovative multifunctional coatings with fascinating stimuliresponsive functionalities are considered“smart”.The stimuli-responsive functionalities of these smart coatings when properly harnessed result in a class of coatings with inherent autonomous control of corrosion.Fundamentally,when metals are exposed to aggressive environments,occurrences at the metalsolution interface cause environmental changes.These changes can be controlled when triggers from external environment set off active components of smart coating,thereby enhancing coating’s life and functionality.Common triggers include the availability of moisture,concentration of chloride ion,p H gradient,mechanical damage,impact,fatigue,light,redox activity and temperature.In this review,recent technological trends in active anticorrosion and self-healing coatings as functional routes for metal protection are summarized,stimuli responsiveness and mechanisms of inhibition are discussed,and recent multi-action protective systems are particularly focused on.
文摘Customized prostheses are normally employed to reconstruct the biomechanics of the pelvis after resection due to tumors or accidents.The objective of this study is to evaluate the biomechanics of the pelvis under different daily activities and to establish a functional evaluation methodology for the customized prostheses.For this purposes,finite element model of a healthy pelvis as well as a reconstructed pelvic model after type II+III resection were built for biomechanical study.The biomechanical perfonnance of the healthy and reconstructed pelvic model was studied under routine activities including standing,knee bending,sitting down,standing up,walking,stair descent and stair ascent.Subsequently,the strength and stability of the prosthesis were evaluated under these activities.Results showed that,for the heathy pelvic model,the stresses were mainly concentrated around the upper part of the sacrum and the sacroiliac joint undergoing different activities,and the maximum stress occurred during stair ascent.As for the reconstructed pelvis,the stress distribution and the tendency of the maximum stress variation predicted for the bone part during all the activities were similar to those of the natural pelvic model,which indicated that the load transferring function of the reconstructed pelvis could be restored by the prosthesis.Moreover,the predicted maximum von Mises stress of the screws and prosthesis was below the fatigue strength of the 3D printed Ti-6A1-4V,which indicated the prosthesis can provide a reliable mechanical performance after implantation.
基金We gratefully acknowledge the support from the National Key R&D Program of China(No.2021YFA1501101)the National Natural Science Foundation of China(No.21971117)+11 种基金the National Natural Science Foundation of China/Research Grant Council of Hong Kong Joint Research Scheme(No.N_PolyU502/21)Functional Research Funds for the Central Universities,Nankai University(No.63186005)Tianjin Key Lab for Rare Earth Materials and Applications(No.ZB19500202)111 Project(No.B18030)from Chinathe Outstanding Youth Project of Tianjin Natural Science Foundation(No.20JCJQJC00130)the funding for Projects of Strategic Importance of The Hong Kong Polytechnic University(Project Code:1-ZE2V)Shenzhen Fundamental Research Scheme-General Program(No.JCYJ20220531090807017)the Key Project of Tianjin Natural Science Foundation(No.20JCZDJC00650)the National Postdoctoral Program for Innovative Talents(No.BX20220157)Open Foundation of State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures(No.2022GXYSOF07)Departmental General Research Fund(Project Code:ZVUL)from Department of Applied Biology and Chemical Technology of Hong Kong Polytechnic UniversityHaihe Laboratory of Sustainable Chemical Transformations.
文摘Currently,single-atom combo catalysts(SACCs)for carbon dioxide reduction reaction(CO_(2)RR)to the formation of HCOOH are still very limited,especially the lanthanide-based SACCs.In this work,the novel SACCs with atomically dispersed In and Ce active sites were successfully prepared on the nitrogen-doped carbon matrix(InCe/CN).Both aberration-corrected high-angle annular dark-field scanning transmission electron microscopy(AC-HAADF-STEM)images and the extended X-ray absorption fine structure(EXAFS)spectra proved the well-isolated In and Ce atoms.The as-prepared InCe/CN shows a high Faradaic efficiency(FE)(77%)and current density of HCOOH formation(j_(HCOOH))at-1.35 V vs.reversible hydrogen electrode(RHE),much higher than the single atom catalysts.Theoretical calculations have indicated that the introduced Ce single atom sites not only significantly promote electron transfer but also optimize the In-5p orbitals towards higher selectivity towards the HCOOH formation.This work innovatively extends the design of SACCs towards the main group and Ln metals for more applications.
基金financially supported by the National Natural Science Foundation of China (22075211, 62005173 and 21601136)Tianjin Science Fund for Distinguished Young Scholars (19JCJQJC61800)+1 种基金the Research Fund of State Key Laboratory for Marine Corrosion and Protection of Luoyang Ship Material Research Institute (LSMRI) under the contract No. KF190411the Science and Technology Development Fund of Tianjin Education Commission for Higher Education (2018KJ126)。
文摘开发高效且性能稳定的氧析出(OER)、氧还原(ORR)和氢析出(HER)三功能催化剂是制备能源存储与转换设备的关键.本文使用一步磷化法,在氮磷共掺杂碳基上制备了Fe Co金属合金/磷化物催化剂(Fe Co-P/PNC).该催化剂显示了良好的ORR性能,展现了0.86 V (vs.RHE,相对于可逆氢电极)的半波电位;在OER和HER反应中,催化剂在10 m A cm^(-2)的电流密度下的过电位分别为350和158 m V.密度泛函理论计算表明,磷在Fe Co磷化物和碳基体中皆起主导作用,使得该催化剂同时具有良好的ORR、OER和HER功能.以Fe Co-P/PNC为空气阴极组装的水系电池和柔性锌-空气电池的峰值功率密度分别为195.1和90.8 m W cm^(-2),且两种电池均具有优异的充放电性能、长寿命和高柔性.此外,自供能的整体水分解系统表现出较低的(1.71 V)工作电压以驱动10 m A cm^(-2)的电流密度,进一步证实了该催化剂出色的多功能性.