To investigate the influence of expansion pretreatment for materials on carbon structure, activated carbons （ACs） were prepared from corncob with/without expansion pretreatment by KOH activation, the structure prope...To investigate the influence of expansion pretreatment for materials on carbon structure, activated carbons （ACs） were prepared from corncob with/without expansion pretreatment by KOH activation, the structure properties of which were determined based on N2 adsorption isotherm at 77 K. The results show that the expansion pretreatment for corncobs is beneficial to the preparation of ACs with high surface area. The specific surface area of the AC derived from corncob with expansion pretreatment （AC-1） is 32.5% larger than that without expansion pretreatment （AC-2）. Furthermore, to probe the potential application of corncob-based ACs in electric double-layer capacitor （EDLC）, the prepared ACs were used as electrode materials to assemble EDLC, and its electrochemical performance was investi- gated. The results indicate that the specific capacitance of AC-I is 276 F/g at 50 mA/g, which increases by 27% com- pared with that of AC-2 （217 F/g）. As electrode materials, AC-1 presents a better electrochemical performance than AC-2, including a higher voltage maintenance ratio and a lower leakage current.展开更多
The effects of magnetic fields on electrochemical processes have made a great impact on both theoretical and practical significances in im- proving capacitor performance. In this study, active carbon/Fe304-NPs nanocom...The effects of magnetic fields on electrochemical processes have made a great impact on both theoretical and practical significances in im- proving capacitor performance. In this study, active carbon/Fe304-NPs nanocomposites （AC/Fe304-NPs） were synthesized using a facile hy- drothermal method and ultrasonic technique. Transmission electron micrographs （TEM） showed that Fe304 nanoparticles （Fe304-NPs） grew along the edge of AC. AC/Fe304-NPs nanocomposites were further used as an electrochemical electrode, and its electrochemical performance was tested under magnetization and non-magnetization conditions, respectively, in a three-electrode electrochemical device. Micro-magnetic field could improve the electric double-layer capacitance, reduce the charge transfer resistance, and enhance the discharge performance. The capacitance enhancement of magnetized electrode was increased by 33.1% at the current density of 1 A/g, and the energy density was improved to 15.97 Wh/kg, due to the addition of magnetic particles.展开更多
基金National Natural Science Foundation of China (No. 50902102 and No. 51172160)
文摘To investigate the influence of expansion pretreatment for materials on carbon structure, activated carbons （ACs） were prepared from corncob with/without expansion pretreatment by KOH activation, the structure properties of which were determined based on N2 adsorption isotherm at 77 K. The results show that the expansion pretreatment for corncobs is beneficial to the preparation of ACs with high surface area. The specific surface area of the AC derived from corncob with expansion pretreatment （AC-1） is 32.5% larger than that without expansion pretreatment （AC-2）. Furthermore, to probe the potential application of corncob-based ACs in electric double-layer capacitor （EDLC）, the prepared ACs were used as electrode materials to assemble EDLC, and its electrochemical performance was investi- gated. The results indicate that the specific capacitance of AC-I is 276 F/g at 50 mA/g, which increases by 27% com- pared with that of AC-2 （217 F/g）. As electrode materials, AC-1 presents a better electrochemical performance than AC-2, including a higher voltage maintenance ratio and a lower leakage current.
基金supported by the National Natural Science Foundation of China(Grant No.21376034 and 21373025)
文摘The effects of magnetic fields on electrochemical processes have made a great impact on both theoretical and practical significances in im- proving capacitor performance. In this study, active carbon/Fe304-NPs nanocomposites （AC/Fe304-NPs） were synthesized using a facile hy- drothermal method and ultrasonic technique. Transmission electron micrographs （TEM） showed that Fe304 nanoparticles （Fe304-NPs） grew along the edge of AC. AC/Fe304-NPs nanocomposites were further used as an electrochemical electrode, and its electrochemical performance was tested under magnetization and non-magnetization conditions, respectively, in a three-electrode electrochemical device. Micro-magnetic field could improve the electric double-layer capacitance, reduce the charge transfer resistance, and enhance the discharge performance. The capacitance enhancement of magnetized electrode was increased by 33.1% at the current density of 1 A/g, and the energy density was improved to 15.97 Wh/kg, due to the addition of magnetic particles.
