Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electro...Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electronic devices,In this work,the zinc-ion hybrid super-capacitor with high volumetric energy density and superb cycle stability had been constructed which employing the high-density threedimensional graphene hydrogel as cathode and Zn foil used as anode in 1 mol/L ZnSO4 electrolyte.Benefiting from the abundant ion transport paths and the abundant active sites for graphene hydrogel with high density and porous structure,the zinc-ion hybrid super-capacitor exhibited an extremely high volumetric energy density of 118.42 Wh/L and a superb power density of 24.00 kW/L,as well as an excellent long cycle life(80% retention after 30,000 cycles at 10 A/g),which was superior to the volumetric energy density of the reported zinc-ion hybrid super-capacitors.This device,based on the fast ion adsorption/deso rption on the capacitor-type graphene cathode and reversible Zn^(2+) plating/stripping on the battery-type Zn anode,which will inspire the development of zinc-ion hybrid super-capacitor in miniaturized devices.展开更多
The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The r...The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The resulting nickel oxide behaved as an electrochemicalcapacitor electrode with a specific capacitance (50-70 F/g) superior to most active carbonelectrodes. This kind of nickel oxide maintained high utilization at high rate of discharge (i.e.,high power density) and had excellent cycle life more than 1000 times, while the capacitance of thecell composed of two identical nickel oxide electrodes was poor at high discharge current densityand the maximum operational voltage of this type capacitor was limited to 0.5 V. A new typesuper-capacitor was designed in which the nickel oxide and the active carbon were applied to thepositive and negative electrodes respectively. The breakdown voltage of this type super-capacitorwas improved effectively to 0.8 V and excellent characteristic of high power discharge was attainedin this way. The Nickel oxide/KOH/Active carbon super-capacitor has promising potentials in portabletelecommunications, uninterruptable power supplies and battery load leveling applications.展开更多
Designing of hetero-atomic doped carbon-based systems through pyrolysis of abundant element organic precursors is a novel approach to construct rational porous carbon materials.Herein,a highly-cross-linked triazine po...Designing of hetero-atomic doped carbon-based systems through pyrolysis of abundant element organic precursors is a novel approach to construct rational porous carbon materials.Herein,a highly-cross-linked triazine polymer is employed to fabricate N,P co-doped porous carbon(A-TDP-12)with tunable active nitrogen in the carbon framework for simultaneous enhancement of CO_(2) capture capability and Supercapacitance(SC).The synthesized A-TDP-12 possesses a typical hierarchically porous framework(micro-pores and meso-pores)with a large surface area(1332 m^(2) g^(-1))and a rich content of N(7.89 at.%)and P(0.74 at.%).It delivers a CO_(2) adsorption capacity of 1.52 and 5.68 mmol g^(-1) at 1 and 5 bar,respectively,with almost no decay after successive 8 recycles.In 6 M KOH aqueous electrolyte,A-TDP-12 exhibits a superior specific capacitance of 172.7 F g^(-1) at a current density of 1 A g^(-1).Even at a high current density of 10 A g^(-1),80%of its initial capacity still remains.This work not only offers a novel strategy for fabricating promising adsorbents and electrodes for CO_(2) uptake and SCs,but also provides new insights into design of porous carbon material for related applications.展开更多
A series of nominal composition Ti/（ZrO2）x（RuO2）l-x （0.1≤x≤0.9） coatings chan-ged in 10% steps was deposited on titanium substrate from RuCl3·nH2O and ZrCl4 containing ethanol solution by thermal decompos...A series of nominal composition Ti/（ZrO2）x（RuO2）l-x （0.1≤x≤0.9） coatings chan-ged in 10% steps was deposited on titanium substrate from RuCl3·nH2O and ZrCl4 containing ethanol solution by thermal decomposition method. The X-ray diffraction （XRD）, high-resolution transmission electron microscopy （HR-TEM） and electrochemical tests were performed to clarify the effects of ZrO2 content on the structure and capacitive property of Ti/（ZrO2）x（RuO2）l-x. The results show that by adding ZrO2 into the coatings the degree of crystallization of RuO2 decreases. The specific capacitance firstly increases and then deceases with the increase of ZrO2 content in the mixed oxide coatings. The film of Ti/（ZrO2）0.6（RuO2）0.4 consisting of amorphous matrix and fine nano-crystalline RuO2 （about 4 nm） has the maximum specific capacitance of 713.27 F/g（RuO2）.展开更多
PbO2/Co3O4 composites were prepared on a Ti substrate by means of a composite electrodeposition method in Pb2+ plating solution containing dissolved nano-Co3O4 particles. X-ray diffraction（XRD）, scanning electron mi...PbO2/Co3O4 composites were prepared on a Ti substrate by means of a composite electrodeposition method in Pb2+ plating solution containing dissolved nano-Co3O4 particles. X-ray diffraction（XRD）, scanning electron microscopy（SEM）, energy dispersive spectrometry（EDS） and transmission electron microscopy（TEM） were used to characterize the chemical composition and morphology of the PbO2/Co3O4 composites. The electrochemical and capacitance performance of the composites were investigated by cyclic voltammetry（CV）, charge-discharge tests and electrochemical impedance（EIS）. The results indicate that the composites comprise rutile phase Co3O4 and β-PbO2. In addition, the surface of the composite electrode is rough and porous. The PbO2/Co3O4 composites exhibit a high specific capacitance up to 215 F/g, which is ten times higher than that of the pure-PbO2 and two times higher than that of the pure-Co3O4 in 1 mol/L NaOH electrolytes.展开更多
Fabric electrode is an emerging electrode element;due to some of its advantages, it can replace traditional conductive gel to become the next generation of electrode. This paper starts from the definition of fabric el...Fabric electrode is an emerging electrode element;due to some of its advantages, it can replace traditional conductive gel to become the next generation of electrode. This paper starts from the definition of fabric electrode, introduces the definition and working principle of fabric electrode, materials of producing electrodes preparation methods, and highlights the fabric used in the myoelectric prosthetic electrodes, supercapacitors and ECG tests.展开更多
System control and safety reliability are important links of the marine DC (Direct Current) power system. The simulationmodel is built by Matlab/Simulink, the battery and super-capacitor are supplied to the system thr...System control and safety reliability are important links of the marine DC (Direct Current) power system. The simulationmodel is built by Matlab/Simulink, the battery and super-capacitor are supplied to the system through a three-phase interleaved DC/DCconverter, the fuse and disconnector switch combination are used as the protection device, and the short-circuit point is set betweeneach branch and the DC distribution board, performing short-circuit simulation. This paper also proposes a short-circuit calculationmethod for super-capacitors based on the simplified model of series RC (Resistors & Capacitors), and verifies its correctness throughsimulation data. The results show that the introduction of a three-phase interleaved DC/DC converter reduces the current ripple andmakes the system control more convenient;short-circuit calculation and simulation have determined the short-circuit withstandcapability of the DC distribution board, and verified the feasibility of the fuse selection method and the short-circuit calculation methodof the super-capacitor. This provides reliable verification for the application and calculation of the actual project.展开更多
This paper describes experiments with our self-built Wave Energy Convertor(WEC)monitoring system in the Maldives and demonstrates how we developed a horizontal-axis type,half-scale,wave energy converter(WEC)that gener...This paper describes experiments with our self-built Wave Energy Convertor(WEC)monitoring system in the Maldives and demonstrates how we developed a horizontal-axis type,half-scale,wave energy converter(WEC)that generates electricity in the coastal breaking wave zone.In order to measure this power generator and turbine’s efficiency,voltage and current were measured by pulling the generator with a 35 cm diameter turbine(half scale).We obtained data showing 400 W peak power in water speed of 3.1 m/s.Consequently,we assembled two sets of WEC,placed them near the shoreline on Kandooma Island in the Maldives in May 2018,and measured the wave energy at the breaking wave zone.A monitoring system was set up in one rack for the two sets of WECs,connected simultaneously.Two outputs of the generators were rectified and connected to power resistors and internal LED displays.The outputs could also be switched to connect to 24 electric double layer capacitors(EDLC),in order to perform a continuous lighting test of external high-power LED lights.The wave power data were continuously saved by an automated data logger and could be transferred from the installation site,to Japan via the Internet.The wave power was measured on Kandooma Island in the Maldives for a long period,and is still ongoing.Examples of the obtained data are shown in this paper.展开更多
To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal v...To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal voltage regulation can be achieved in a DCMG simultaneously.The proposed control displays good plug-and-play features using only local measurements.For quantitative analysis and effective design of the critical parameter of unified control,two indices,equivalent power supporting time and inertia contributed by the unified controlled SC system,are introduced firstly.Then,with a simple but effective reduced-order model of a DCMG,analytical solutions are obtained for the two indices.In addition,a systematic design method is presented for the proposed unified control.Finally,to verify the proposed unified control,a switching model is developed for a typical DCMG in PSCAD/EMTDC,and theoretical analyses are conducted for different operating conditions.展开更多
For the first time dry roller vibration milling at room temperature was used to prepare active carbon （AC） nano-particles and to modify MnO2 powder as electrode materials. In 30 min AC was milled to a mean particle ...For the first time dry roller vibration milling at room temperature was used to prepare active carbon （AC） nano-particles and to modify MnO2 powder as electrode materials. In 30 min AC was milled to a mean particle size of 30-50 nm with increased crystallinity and higher specific surface area, predominantly mesoporous and with improved pore diameter distribution. Then, AC nano-particles were incorporated with MnO2 or bismuth-doped MnO2 nano-particles synthesized by sol-gel methods to prepare nano-composite electrode materials for studying their electrochemical performance. The AC nano-particles combined with 10 wt.% bismuth-doped MnO2 nano-particles were found to possess excellent electrochemical property with specific capacitance up to 308 F/g and without obvious attenuation with increasing current. Our method seems to ooen a new way to imorove AC based electrode materials used for clean energy such as suner capacitors.展开更多
基金supported by the National Nature Science Foundations of China (No.21965019)the China Postdoctoral Science Foundation (No.2017M613248)+1 种基金the Natural Science Foundation of Gansu Province (No.1506 RJZA091)the Scientific Research Foundation of the Higher Education Institutions of Gansu Province (No.2015A-037)。
文摘Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electronic devices,In this work,the zinc-ion hybrid super-capacitor with high volumetric energy density and superb cycle stability had been constructed which employing the high-density threedimensional graphene hydrogel as cathode and Zn foil used as anode in 1 mol/L ZnSO4 electrolyte.Benefiting from the abundant ion transport paths and the abundant active sites for graphene hydrogel with high density and porous structure,the zinc-ion hybrid super-capacitor exhibited an extremely high volumetric energy density of 118.42 Wh/L and a superb power density of 24.00 kW/L,as well as an excellent long cycle life(80% retention after 30,000 cycles at 10 A/g),which was superior to the volumetric energy density of the reported zinc-ion hybrid super-capacitors.This device,based on the fast ion adsorption/deso rption on the capacitor-type graphene cathode and reversible Zn^(2+) plating/stripping on the battery-type Zn anode,which will inspire the development of zinc-ion hybrid super-capacitor in miniaturized devices.
基金the National Natural Science Foundation of China (No.59807001).
文摘The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The resulting nickel oxide behaved as an electrochemicalcapacitor electrode with a specific capacitance (50-70 F/g) superior to most active carbonelectrodes. This kind of nickel oxide maintained high utilization at high rate of discharge (i.e.,high power density) and had excellent cycle life more than 1000 times, while the capacitance of thecell composed of two identical nickel oxide electrodes was poor at high discharge current densityand the maximum operational voltage of this type capacitor was limited to 0.5 V. A new typesuper-capacitor was designed in which the nickel oxide and the active carbon were applied to thepositive and negative electrodes respectively. The breakdown voltage of this type super-capacitorwas improved effectively to 0.8 V and excellent characteristic of high power discharge was attainedin this way. The Nickel oxide/KOH/Active carbon super-capacitor has promising potentials in portabletelecommunications, uninterruptable power supplies and battery load leveling applications.
基金supported by the National Natural Science Foundation of China (21978182)
文摘Designing of hetero-atomic doped carbon-based systems through pyrolysis of abundant element organic precursors is a novel approach to construct rational porous carbon materials.Herein,a highly-cross-linked triazine polymer is employed to fabricate N,P co-doped porous carbon(A-TDP-12)with tunable active nitrogen in the carbon framework for simultaneous enhancement of CO_(2) capture capability and Supercapacitance(SC).The synthesized A-TDP-12 possesses a typical hierarchically porous framework(micro-pores and meso-pores)with a large surface area(1332 m^(2) g^(-1))and a rich content of N(7.89 at.%)and P(0.74 at.%).It delivers a CO_(2) adsorption capacity of 1.52 and 5.68 mmol g^(-1) at 1 and 5 bar,respectively,with almost no decay after successive 8 recycles.In 6 M KOH aqueous electrolyte,A-TDP-12 exhibits a superior specific capacitance of 172.7 F g^(-1) at a current density of 1 A g^(-1).Even at a high current density of 10 A g^(-1),80%of its initial capacity still remains.This work not only offers a novel strategy for fabricating promising adsorbents and electrodes for CO_(2) uptake and SCs,but also provides new insights into design of porous carbon material for related applications.
基金Supported by the National High Technology Research and Development Projects (863) of China (2007AA03Z325)the Natural Science Foundation of China (50472002)+1 种基金Provincial Science Foundation of Fujian (2009J05116)the program for Innovative Research Team in Fuzhou University
文摘A series of nominal composition Ti/（ZrO2）x（RuO2）l-x （0.1≤x≤0.9） coatings chan-ged in 10% steps was deposited on titanium substrate from RuCl3·nH2O and ZrCl4 containing ethanol solution by thermal decomposition method. The X-ray diffraction （XRD）, high-resolution transmission electron microscopy （HR-TEM） and electrochemical tests were performed to clarify the effects of ZrO2 content on the structure and capacitive property of Ti/（ZrO2）x（RuO2）l-x. The results show that by adding ZrO2 into the coatings the degree of crystallization of RuO2 decreases. The specific capacitance firstly increases and then deceases with the increase of ZrO2 content in the mixed oxide coatings. The film of Ti/（ZrO2）0.6（RuO2）0.4 consisting of amorphous matrix and fine nano-crystalline RuO2 （about 4 nm） has the maximum specific capacitance of 713.27 F/g（RuO2）.
基金Supported by the National Natural Science Foundation of China(No.51502117,No.21671084)Key Research&Development Plan of Zhenjiang City(No.SH2017051)+1 种基金Foundation from Marine Equipment and Technology Institute for Jiangsu University of Science and Technology(No.HZ20170015)Six Talent Peaks Project in Jiangsu Province(No.2014-XCL-008)
文摘PbO2/Co3O4 composites were prepared on a Ti substrate by means of a composite electrodeposition method in Pb2+ plating solution containing dissolved nano-Co3O4 particles. X-ray diffraction（XRD）, scanning electron microscopy（SEM）, energy dispersive spectrometry（EDS） and transmission electron microscopy（TEM） were used to characterize the chemical composition and morphology of the PbO2/Co3O4 composites. The electrochemical and capacitance performance of the composites were investigated by cyclic voltammetry（CV）, charge-discharge tests and electrochemical impedance（EIS）. The results indicate that the composites comprise rutile phase Co3O4 and β-PbO2. In addition, the surface of the composite electrode is rough and porous. The PbO2/Co3O4 composites exhibit a high specific capacitance up to 215 F/g, which is ten times higher than that of the pure-PbO2 and two times higher than that of the pure-Co3O4 in 1 mol/L NaOH electrolytes.
文摘Fabric electrode is an emerging electrode element;due to some of its advantages, it can replace traditional conductive gel to become the next generation of electrode. This paper starts from the definition of fabric electrode, introduces the definition and working principle of fabric electrode, materials of producing electrodes preparation methods, and highlights the fabric used in the myoelectric prosthetic electrodes, supercapacitors and ECG tests.
文摘System control and safety reliability are important links of the marine DC (Direct Current) power system. The simulationmodel is built by Matlab/Simulink, the battery and super-capacitor are supplied to the system through a three-phase interleaved DC/DCconverter, the fuse and disconnector switch combination are used as the protection device, and the short-circuit point is set betweeneach branch and the DC distribution board, performing short-circuit simulation. This paper also proposes a short-circuit calculationmethod for super-capacitors based on the simplified model of series RC (Resistors & Capacitors), and verifies its correctness throughsimulation data. The results show that the introduction of a three-phase interleaved DC/DC converter reduces the current ripple andmakes the system control more convenient;short-circuit calculation and simulation have determined the short-circuit withstandcapability of the DC distribution board, and verified the feasibility of the fuse selection method and the short-circuit calculation methodof the super-capacitor. This provides reliable verification for the application and calculation of the actual project.
文摘This paper describes experiments with our self-built Wave Energy Convertor(WEC)monitoring system in the Maldives and demonstrates how we developed a horizontal-axis type,half-scale,wave energy converter(WEC)that generates electricity in the coastal breaking wave zone.In order to measure this power generator and turbine’s efficiency,voltage and current were measured by pulling the generator with a 35 cm diameter turbine(half scale).We obtained data showing 400 W peak power in water speed of 3.1 m/s.Consequently,we assembled two sets of WEC,placed them near the shoreline on Kandooma Island in the Maldives in May 2018,and measured the wave energy at the breaking wave zone.A monitoring system was set up in one rack for the two sets of WECs,connected simultaneously.Two outputs of the generators were rectified and connected to power resistors and internal LED displays.The outputs could also be switched to connect to 24 electric double layer capacitors(EDLC),in order to perform a continuous lighting test of external high-power LED lights.The wave power data were continuously saved by an automated data logger and could be transferred from the installation site,to Japan via the Internet.The wave power was measured on Kandooma Island in the Maldives for a long period,and is still ongoing.Examples of the obtained data are shown in this paper.
基金supported in part by the National Nature Science Foundation(No.51977142)National Key R&D Program of China(No.2020YFB1506803)Tianjin Natural Science Foundation(No.20JCQNJC00350)。
文摘To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal voltage regulation can be achieved in a DCMG simultaneously.The proposed control displays good plug-and-play features using only local measurements.For quantitative analysis and effective design of the critical parameter of unified control,two indices,equivalent power supporting time and inertia contributed by the unified controlled SC system,are introduced firstly.Then,with a simple but effective reduced-order model of a DCMG,analytical solutions are obtained for the two indices.In addition,a systematic design method is presented for the proposed unified control.Finally,to verify the proposed unified control,a switching model is developed for a typical DCMG in PSCAD/EMTDC,and theoretical analyses are conducted for different operating conditions.
基金Shanghai Nano-technology Special Fund,Grant No.05nm05027Shanghai Education Fund,Grant No.05EE09.
文摘For the first time dry roller vibration milling at room temperature was used to prepare active carbon （AC） nano-particles and to modify MnO2 powder as electrode materials. In 30 min AC was milled to a mean particle size of 30-50 nm with increased crystallinity and higher specific surface area, predominantly mesoporous and with improved pore diameter distribution. Then, AC nano-particles were incorporated with MnO2 or bismuth-doped MnO2 nano-particles synthesized by sol-gel methods to prepare nano-composite electrode materials for studying their electrochemical performance. The AC nano-particles combined with 10 wt.% bismuth-doped MnO2 nano-particles were found to possess excellent electrochemical property with specific capacitance up to 308 F/g and without obvious attenuation with increasing current. Our method seems to ooen a new way to imorove AC based electrode materials used for clean energy such as suner capacitors.
