Poor conductivity,sluggish ion diffusion kinetics and short cycle life hinder the further development of manganese oxide in aqueous zinc-ion batteries(AZIBs).Exploring a cathode with high capacity and long cycle life ...Poor conductivity,sluggish ion diffusion kinetics and short cycle life hinder the further development of manganese oxide in aqueous zinc-ion batteries(AZIBs).Exploring a cathode with high capacity and long cycle life is critical to the commercial development of AZIBs.Herein,a two-dimensional(2D) MnO/C composite derived from metal organic framework(MOF) was prepared.The 2D MnO/C cathode exhibits a remarkably cyclic stability with the capacity retention of 90.6% after 900 cycles at 0.5 A·g^(-1) and maintains a high capacity of 120.2 mAh·g^(-1)after 4500 cycles at 1.0 A·g^(-1).It is demonstrated that MnO is converted into Mn_(3)O_(4) through electrochemical activation strategy and shows a Zn^(2+)and H^(+)co-intercalation mechanism.In general,this work provides a new path for the development of high-performance AZIBs cathode with controllable morphology.展开更多
Lithium-ion batteries （LIBs） are currently recognized as one of the most popular power sources available. To construct advanced LIBs exhibiting long-term endurance, great attention has been paid to enhancing their p...Lithium-ion batteries （LIBs） are currently recognized as one of the most popular power sources available. To construct advanced LIBs exhibiting long-term endurance, great attention has been paid to enhancing their poor cycle stabilities. As the performance of LIBs is dependent on the electrode materials employed, the most promising approach to improve their life span is the design of novel electrode materials. We herein describe the rational design of a three-dimensional （3D） porous MnO/C-N nanoarchitecture as an anode material for long cycle life LIBs based on their preparation from inexpensive, renewable, and abundant rapeseed pollen （R-pollen） via a facile immersion-annealing route. Remarkably, the as-prepared MnO/C-N with its optimized 3D nanostructure exhibited a high specific capacity （756.5 mAh·g^-1 at a rate of 100 mA·g^-1）, long life span （specific discharge capacity of 513.0 mAh·g^-1, -95.16% of the initial reversible capacity, after 400 cycles at 300 mA·g^-1）, and good rate capability. This material therefore represents a promising alternative candidate for the high-performance anode of next-generation LIBs.展开更多
MnO2-impregnated carbon-coated Fe3 O4(Fe3O4/C/MnO2)nanocomposites with a good core-shell structure were prepared by direct oxidation of carbon-coated Fe3 O4(Fe3O4/C)microspheres with KMnO4 in alkaline solution and app...MnO2-impregnated carbon-coated Fe3 O4(Fe3O4/C/MnO2)nanocomposites with a good core-shell structure were prepared by direct oxidation of carbon-coated Fe3 O4(Fe3O4/C)microspheres with KMnO4 in alkaline solution and applied to adsorb bovine serum albumin(BSA).X-ray diffraction(XRD),transmission electron microscope(TEM),Fourier transform infrared spectrometer(FTIR),vibrating sample magnetometer(VSM)and thermogravimetric analyzer(TGA)tests show that Fe3O4/C microspheres were newly functionalized via the oxidation by KMnO4.Fe3O4/C/MnO2 nanocomposites exhibit a higher adsorption capacity for BSA than Fe3O4/C microspheres and the maximum adsorption of BSA on them occurs at pH 4.7,which is the isoelectric point of BSA.Langmuir isotherm model describes the adsorption of BSA better than Freundlich model and Temkin model,and the kinetics data fit well with the pseudo-second-order model.展开更多
以氯化胆碱-乙二醇低共熔溶剂为反应介质,采用沉淀法制备了锂离子电池负极材料一氧化锰/碳多孔微球,并用X射线衍射(XRD)、扫描电镜(SEM)、比表面积及孔径分析、恒电流充放电技术、电化学阻抗谱和循环伏安等手段,研究了碳酸氢铵与氯化锰...以氯化胆碱-乙二醇低共熔溶剂为反应介质,采用沉淀法制备了锂离子电池负极材料一氧化锰/碳多孔微球,并用X射线衍射(XRD)、扫描电镜(SEM)、比表面积及孔径分析、恒电流充放电技术、电化学阻抗谱和循环伏安等手段,研究了碳酸氢铵与氯化锰物质的量比对一氧化锰/碳材料的形貌、结构及电化学性能的影响。结果表明,一氧化锰/碳材料的比表面积、孔径、孔体积、比容量、循环性能和倍率性能均随着碳酸氢铵与氯化锰物质的量比的增加而先增大后减小,碳酸氢铵与氯化锰物质的量比为2.0∶1时制备的一氧化锰/碳材料为多孔球体颗粒,粒径为0.5~2.5μm、平均孔径为11.5 nm、比表面积高达127.7 m2/g。一氧化锰/碳多孔微球材料在1C测试条件下的放电比容量为830 m A·h/g,循环50次后容量保持率接近100%,具有较高的比容量和较好的循环性能。展开更多
以一水合硫酸锰、碳酸氢铵为原料,采用T型微反应器共沉淀法制备了球形碳酸锰,以该碳酸锰为前驱体,蔗糖为碳源煅烧后得到球形多孔一氧化锰/碳锂离子电池负极材料。利用X射线衍射(XRD)、扫描电镜(SEM)、氮气吸附-脱附曲线、恒电流充放电...以一水合硫酸锰、碳酸氢铵为原料,采用T型微反应器共沉淀法制备了球形碳酸锰,以该碳酸锰为前驱体,蔗糖为碳源煅烧后得到球形多孔一氧化锰/碳锂离子电池负极材料。利用X射线衍射(XRD)、扫描电镜(SEM)、氮气吸附-脱附曲线、恒电流充放电测试、交流阻抗(EIS)和循环伏安(CV)等方法研究了原料浓度比对一氧化锰/碳电极材料的结构、形态和电化学性能的影响。结果表明,首次放电比容量可以达到1 129.69 m A·h/g,第二圈的放电比容量为707.03 m A·h/g,接近于理论比容量,循环50圈以后,容量仍可以保持在576.93 m A·h/g,显示出较好的电化学性能。展开更多
基金financially supported by the National Natural Science Foundation of China (Nos.22078200 and 51874199)Guangdong Basic and Applied Basic Research Foundation (No.2021A1515010162)。
文摘Poor conductivity,sluggish ion diffusion kinetics and short cycle life hinder the further development of manganese oxide in aqueous zinc-ion batteries(AZIBs).Exploring a cathode with high capacity and long cycle life is critical to the commercial development of AZIBs.Herein,a two-dimensional(2D) MnO/C composite derived from metal organic framework(MOF) was prepared.The 2D MnO/C cathode exhibits a remarkably cyclic stability with the capacity retention of 90.6% after 900 cycles at 0.5 A·g^(-1) and maintains a high capacity of 120.2 mAh·g^(-1)after 4500 cycles at 1.0 A·g^(-1).It is demonstrated that MnO is converted into Mn_(3)O_(4) through electrochemical activation strategy and shows a Zn^(2+)and H^(+)co-intercalation mechanism.In general,this work provides a new path for the development of high-performance AZIBs cathode with controllable morphology.
基金Acknowledgements This work is supported by the National Natural Science Foundation of China （Nos. 21431006 and 21503207）, the Foundation for Innovative Research Groups of the National Natural Science Foundation of China （No. 21521001）, the National Basic Research Program of China （Nos. 2014CB931800, 2013CB933900）, and Scientific Research Grant of Hefei Science Center of Chinese Academy of Sciences （Nos. 2015HSC-UE007 and 2015SRG-HSC038）, the China Postdoctoral Science Foundation （Nos. 2015T80662 and 2014M550346）, and the Fundamental Research Funds for the Central Universities （No. WK2060190047）. The authors also thank the help provided by Dr. Yue Lin and Prof. Yan-Wei Ding in Instruments＇ Center for Physical Science at the University of Science and Technology of China.
文摘Lithium-ion batteries （LIBs） are currently recognized as one of the most popular power sources available. To construct advanced LIBs exhibiting long-term endurance, great attention has been paid to enhancing their poor cycle stabilities. As the performance of LIBs is dependent on the electrode materials employed, the most promising approach to improve their life span is the design of novel electrode materials. We herein describe the rational design of a three-dimensional （3D） porous MnO/C-N nanoarchitecture as an anode material for long cycle life LIBs based on their preparation from inexpensive, renewable, and abundant rapeseed pollen （R-pollen） via a facile immersion-annealing route. Remarkably, the as-prepared MnO/C-N with its optimized 3D nanostructure exhibited a high specific capacity （756.5 mAh·g^-1 at a rate of 100 mA·g^-1）, long life span （specific discharge capacity of 513.0 mAh·g^-1, -95.16% of the initial reversible capacity, after 400 cycles at 300 mA·g^-1）, and good rate capability. This material therefore represents a promising alternative candidate for the high-performance anode of next-generation LIBs.
基金financially supported by the National Science and Technology Major Project of China for Water Pollution Control and Treatment(No.2013ZX07202-010)。
文摘MnO2-impregnated carbon-coated Fe3 O4(Fe3O4/C/MnO2)nanocomposites with a good core-shell structure were prepared by direct oxidation of carbon-coated Fe3 O4(Fe3O4/C)microspheres with KMnO4 in alkaline solution and applied to adsorb bovine serum albumin(BSA).X-ray diffraction(XRD),transmission electron microscope(TEM),Fourier transform infrared spectrometer(FTIR),vibrating sample magnetometer(VSM)and thermogravimetric analyzer(TGA)tests show that Fe3O4/C microspheres were newly functionalized via the oxidation by KMnO4.Fe3O4/C/MnO2 nanocomposites exhibit a higher adsorption capacity for BSA than Fe3O4/C microspheres and the maximum adsorption of BSA on them occurs at pH 4.7,which is the isoelectric point of BSA.Langmuir isotherm model describes the adsorption of BSA better than Freundlich model and Temkin model,and the kinetics data fit well with the pseudo-second-order model.
文摘以氯化胆碱-乙二醇低共熔溶剂为反应介质,采用沉淀法制备了锂离子电池负极材料一氧化锰/碳多孔微球,并用X射线衍射(XRD)、扫描电镜(SEM)、比表面积及孔径分析、恒电流充放电技术、电化学阻抗谱和循环伏安等手段,研究了碳酸氢铵与氯化锰物质的量比对一氧化锰/碳材料的形貌、结构及电化学性能的影响。结果表明,一氧化锰/碳材料的比表面积、孔径、孔体积、比容量、循环性能和倍率性能均随着碳酸氢铵与氯化锰物质的量比的增加而先增大后减小,碳酸氢铵与氯化锰物质的量比为2.0∶1时制备的一氧化锰/碳材料为多孔球体颗粒,粒径为0.5~2.5μm、平均孔径为11.5 nm、比表面积高达127.7 m2/g。一氧化锰/碳多孔微球材料在1C测试条件下的放电比容量为830 m A·h/g,循环50次后容量保持率接近100%,具有较高的比容量和较好的循环性能。
文摘以一水合硫酸锰、碳酸氢铵为原料,采用T型微反应器共沉淀法制备了球形碳酸锰,以该碳酸锰为前驱体,蔗糖为碳源煅烧后得到球形多孔一氧化锰/碳锂离子电池负极材料。利用X射线衍射(XRD)、扫描电镜(SEM)、氮气吸附-脱附曲线、恒电流充放电测试、交流阻抗(EIS)和循环伏安(CV)等方法研究了原料浓度比对一氧化锰/碳电极材料的结构、形态和电化学性能的影响。结果表明,首次放电比容量可以达到1 129.69 m A·h/g,第二圈的放电比容量为707.03 m A·h/g,接近于理论比容量,循环50圈以后,容量仍可以保持在576.93 m A·h/g,显示出较好的电化学性能。
