The low sulfur utilization and fast capacity fading resulting from the sluggish redox reaction and abominable polysulfides shuttle greatly hinder the practical applications of lithium-sulfur(Li-S) batteries.Herein, we...The low sulfur utilization and fast capacity fading resulting from the sluggish redox reaction and abominable polysulfides shuttle greatly hinder the practical applications of lithium-sulfur(Li-S) batteries.Herein, we develop a facile "in-situ growth" method to decorate ultra-small Mo2 C nanoparticles(USMo2 C) on the surface of Ketjen Black(KB) to functionalize the commercial polypropylene(PP) separators,which can accelerate the redox kinetics of lithium polysulfides conversion and effectively increase the utilization of sulfur for Li-S batteries. Importantly, the US-Mo2 C nanoparticles have abundant sites for chemical adsorption towards polysulfides and the conductive carbon networks of KB have cross-linked pore channels, which can promote electron transport and provide physical barrier and volume expansion space for polysulfides. Due to the combined effects of the US-Mo2 C and KB, Li-S cells employing the multifunctional PP separators modified with KB/US-Mo2 C composite(KB/US-Mo2 C@PP) exhibit a high specific capacity(1212.8 mAh g^(-1) at 0.2 C), and maintain a reversible capacity of 1053.3 m Ah g^(-1) after 100 cycles.More importantly, the KB/US-Mo2 C@PP cells with higher sulfur mass loading of 4.9 mg cm^(-2) have superb areal capacity of 2.3 mAh cm^(-2). This work offers a novel and promising perspective for high-performance Li-S batteries from both the shuttle effect and the complex polysulfides conversion.展开更多
Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is p...Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is proposed to construct copper sulfides-loaded dual-mesoporous silica nanospheres(Cux-Sy@DMSNs)with various crystal phases for reactive oxygen species(ROS)-mediated and photothermal antibacterial application.With the pore confinement of DMSNs,the crystal phases of copper sulfides including CuS,Cu_(9)S_(5)and Cui.96S can be easily controlled by changing the vulcanization temperature.The relationships between the crystal phases and photothermal properties as well as peroxidase-like activity of copper sulfides were systematically investigated.Results show that the obtained CuS@DMSNs exhibited higher photothermal ability with remarkable photothermal conversion efficiency of 36.86%in the second near-infrared region(NIR-II)and better peroxidase-like activity,compared to those of Cu_(9)S_(5)@DMSNs and Cu_(1.96)S@DMSNs.As a result,the in vitro experiments showed the good antibacterial effect against both gram-negative E.coli and gram-positive S.aureus under 1064 nm laser irradiation and the presence of H_(2)O_(2).Besides,the CCK-8 assay indicated that CuS@p-DMSNs have minimal cytotoxicity against normal human umbilical vein endothelial cells at the ranged concentrations.Therefore,the resultant CuS@p-DMSNs could act as a promising antibacterial agent for deep wound bacterial infection treatment.展开更多
锂硫电池固有的缓慢转化动力学和严重的穿梭效应导致其可逆容量和循环寿命差,严重阻碍了其实际应用.为了解决这些问题,我们设计并构建了一种Ni/Ni_(2)P异质结嵌入介孔碳纳米球的复合材料(Ni/Ni_(2)P-MCN),将其用于锂硫电池隔膜改性以促...锂硫电池固有的缓慢转化动力学和严重的穿梭效应导致其可逆容量和循环寿命差,严重阻碍了其实际应用.为了解决这些问题,我们设计并构建了一种Ni/Ni_(2)P异质结嵌入介孔碳纳米球的复合材料(Ni/Ni_(2)P-MCN),将其用于锂硫电池隔膜改性以促进多硫化物的催化转化.研究发现,Ni/Ni_(2)P-MCN改性隔膜可以通过丰富的异质结化学吸附位点吸附多硫化物、抑制穿梭效应,而且对多硫化物的转化具有优异的催化活性.此外,具有暴露介孔结构的导电碳球可以作为物理屏障,容纳沉积的不溶性Li_(2)S.因此,使用Ni/Ni_(2)P-MCN改性隔膜的电池显示出优异的倍率性能(5 C下431 mA h g^(-1))和循环稳定性(1500次循环下平均容量衰减约0.031%).在4.2 mg cm^(-2)的高载硫下,输出面积比容量约3.5 mA h cm^(-2).我们认为,这种独特的Ni/Ni_(2)P异质结/多孔碳复合材料在高性能、可持续储能器件中具备巨大的应用潜力.展开更多
The architecture control of mesoporous materials at the mesoscale is of great importance to their properties and resultant potential applications[1,2].To synthesize mesoporous materials with expected morphologies or m...The architecture control of mesoporous materials at the mesoscale is of great importance to their properties and resultant potential applications[1,2].To synthesize mesoporous materials with expected morphologies or mesostructures,numerous synthetic protocols have been developed[3–6],which have witnessed the significant progress in the construction of mesoporous materials with various morphologies or mesostructures.However,it remains a great challenge to build a visualized relationship between organic templates and the desired architectures of the inorganic products.展开更多
基金financially supported by the National Natural Science Foundation of China for Innovative Research Groups (No. 51621002)the National Key Research and Development Program of China (Grant No. 2016YFA0203700)+5 种基金NSFC (Grant No 51672083)Program of Shanghai Academic/Technology Research Leader (18XD1401400)Basic Research Program of Shanghai (17JC1404702)Leading talents in Shanghai in 2018The Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, the 111 project (B14018)The Fundamental Research Funds for Central Universities (222201718002)。
文摘The low sulfur utilization and fast capacity fading resulting from the sluggish redox reaction and abominable polysulfides shuttle greatly hinder the practical applications of lithium-sulfur(Li-S) batteries.Herein, we develop a facile "in-situ growth" method to decorate ultra-small Mo2 C nanoparticles(USMo2 C) on the surface of Ketjen Black(KB) to functionalize the commercial polypropylene(PP) separators,which can accelerate the redox kinetics of lithium polysulfides conversion and effectively increase the utilization of sulfur for Li-S batteries. Importantly, the US-Mo2 C nanoparticles have abundant sites for chemical adsorption towards polysulfides and the conductive carbon networks of KB have cross-linked pore channels, which can promote electron transport and provide physical barrier and volume expansion space for polysulfides. Due to the combined effects of the US-Mo2 C and KB, Li-S cells employing the multifunctional PP separators modified with KB/US-Mo2 C composite(KB/US-Mo2 C@PP) exhibit a high specific capacity(1212.8 mAh g^(-1) at 0.2 C), and maintain a reversible capacity of 1053.3 m Ah g^(-1) after 100 cycles.More importantly, the KB/US-Mo2 C@PP cells with higher sulfur mass loading of 4.9 mg cm^(-2) have superb areal capacity of 2.3 mAh cm^(-2). This work offers a novel and promising perspective for high-performance Li-S batteries from both the shuttle effect and the complex polysulfides conversion.
基金supported by the National Natural Science Foundation of China(grant No.52072124 and 51972112)Natural Science Foundation of Shanghai(grant No.20zR1414900)+1 种基金Program of Shanghai Academic/Technology Research Leader(grant No.22XD1421100)The Fundamental Research Funds for the Central Universities,and the 111 project(grant No.B14018).
文摘Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is proposed to construct copper sulfides-loaded dual-mesoporous silica nanospheres(Cux-Sy@DMSNs)with various crystal phases for reactive oxygen species(ROS)-mediated and photothermal antibacterial application.With the pore confinement of DMSNs,the crystal phases of copper sulfides including CuS,Cu_(9)S_(5)and Cui.96S can be easily controlled by changing the vulcanization temperature.The relationships between the crystal phases and photothermal properties as well as peroxidase-like activity of copper sulfides were systematically investigated.Results show that the obtained CuS@DMSNs exhibited higher photothermal ability with remarkable photothermal conversion efficiency of 36.86%in the second near-infrared region(NIR-II)and better peroxidase-like activity,compared to those of Cu_(9)S_(5)@DMSNs and Cu_(1.96)S@DMSNs.As a result,the in vitro experiments showed the good antibacterial effect against both gram-negative E.coli and gram-positive S.aureus under 1064 nm laser irradiation and the presence of H_(2)O_(2).Besides,the CCK-8 assay indicated that CuS@p-DMSNs have minimal cytotoxicity against normal human umbilical vein endothelial cells at the ranged concentrations.Therefore,the resultant CuS@p-DMSNs could act as a promising antibacterial agent for deep wound bacterial infection treatment.
基金supported by the National Key Research and Development Program of China (2016YFA0203700)the National Natural Science Foundation of China (51672083, 51962022 and 52072124)+4 种基金the Natural Science Foundation of Shanghai (20ZR1414900)the Program of Shanghai Academic/Technology Research Leader (18XD1401400)the Leading Talents in Shanghai in 2018the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learningthe 111 Project (B14018)。
基金financially supported by the National Natural Science Foundation of China(52072124)Shanghai Municipal Science and Technology Major Project(2018SHZDZX03)+3 种基金the Natural Science Foundation of Shanghai(20ZR1414900)the Leading Talents in Shanghai in2018the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningthe 111 Project(B14018)。
文摘锂硫电池固有的缓慢转化动力学和严重的穿梭效应导致其可逆容量和循环寿命差,严重阻碍了其实际应用.为了解决这些问题,我们设计并构建了一种Ni/Ni_(2)P异质结嵌入介孔碳纳米球的复合材料(Ni/Ni_(2)P-MCN),将其用于锂硫电池隔膜改性以促进多硫化物的催化转化.研究发现,Ni/Ni_(2)P-MCN改性隔膜可以通过丰富的异质结化学吸附位点吸附多硫化物、抑制穿梭效应,而且对多硫化物的转化具有优异的催化活性.此外,具有暴露介孔结构的导电碳球可以作为物理屏障,容纳沉积的不溶性Li_(2)S.因此,使用Ni/Ni_(2)P-MCN改性隔膜的电池显示出优异的倍率性能(5 C下431 mA h g^(-1))和循环稳定性(1500次循环下平均容量衰减约0.031%).在4.2 mg cm^(-2)的高载硫下,输出面积比容量约3.5 mA h cm^(-2).我们认为,这种独特的Ni/Ni_(2)P异质结/多孔碳复合材料在高性能、可持续储能器件中具备巨大的应用潜力.
基金the National Key Research and Development Program of China(2018YFC1105702 and 2016YFA0203700)the National Natural Science Foundation of China(51621002 and 51972112)+5 种基金Program of Shanghai Academic/Technology Research Leader(18XD1401400)Basic Research Program of Shanghai(17JC1404702 and 19JC1411700)Leading Talents in Shanghai in 2018the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningthe 111 Project(B14018)the Fundamental Research Funds for Central Universities(222201718002)。
文摘The architecture control of mesoporous materials at the mesoscale is of great importance to their properties and resultant potential applications[1,2].To synthesize mesoporous materials with expected morphologies or mesostructures,numerous synthetic protocols have been developed[3–6],which have witnessed the significant progress in the construction of mesoporous materials with various morphologies or mesostructures.However,it remains a great challenge to build a visualized relationship between organic templates and the desired architectures of the inorganic products.
