The structures of electrode meso-macropore and the solvent polarity are the crucial factors dominating the performance of the electric double layer capacitors(EDLCs),but their impacts are usually tangled and difficult...The structures of electrode meso-macropore and the solvent polarity are the crucial factors dominating the performance of the electric double layer capacitors(EDLCs),but their impacts are usually tangled and difficult to decouple and quantitate.Here the effects of electrode meso-macropore structure and solvent polarity on the specific capacitance of an EDLC are quantitatively investigated using a steady-state continuum model.The simulation results indicate the specific capacitances are significantly affected by the meso-macropore surface structure.The specific capacitances significantly decrease for both convex surface structures but obviously increase for both concave surface structures,with the increase of curvature radius from 1 to 20 nm.As for solvents,the polar solvent with high saturated dielectric permittivity improves the capacitance performance.Moreover,the electrode meso-macropore structure is of more concern compared with solvent polarity when aiming at enhancing the specific capacitance.These results provide fundamentals for the rational design of porous electrodes and polar electrolytes for EDLCs.展开更多
Dielectric and rotational viscosity measurements of a multi-component ferroelectric liquid crystal mixture were performed by adding a small concentration (0.01 wt%) of silica and multi walled carbon nanotubes (MWC...Dielectric and rotational viscosity measurements of a multi-component ferroelectric liquid crystal mixture were performed by adding a small concentration (0.01 wt%) of silica and multi walled carbon nanotubes (MWCNTs). Liquid crystals turn out to be outstanding hosts for nanomaterials. A remarkable increase in the rotational viscosity was noticed in CNT doped system as compared to silica doped same liquid crystal system. Comparison of dielectric studies shows higher value of permittivity and dielectric losses for silica-doped sample than those of CNT doped sample. The results have been interpreted both experimentally and theoretically.展开更多
基金financially supported by the National Basic Research Program of China(2014CB239702)the National Natural Science Foundation of China(21676082,22008067)the China Postdoctoral Science Foundation(2020M681202,2021T140204)。
文摘The structures of electrode meso-macropore and the solvent polarity are the crucial factors dominating the performance of the electric double layer capacitors(EDLCs),but their impacts are usually tangled and difficult to decouple and quantitate.Here the effects of electrode meso-macropore structure and solvent polarity on the specific capacitance of an EDLC are quantitatively investigated using a steady-state continuum model.The simulation results indicate the specific capacitances are significantly affected by the meso-macropore surface structure.The specific capacitances significantly decrease for both convex surface structures but obviously increase for both concave surface structures,with the increase of curvature radius from 1 to 20 nm.As for solvents,the polar solvent with high saturated dielectric permittivity improves the capacitance performance.Moreover,the electrode meso-macropore structure is of more concern compared with solvent polarity when aiming at enhancing the specific capacitance.These results provide fundamentals for the rational design of porous electrodes and polar electrolytes for EDLCs.
文摘Dielectric and rotational viscosity measurements of a multi-component ferroelectric liquid crystal mixture were performed by adding a small concentration (0.01 wt%) of silica and multi walled carbon nanotubes (MWCNTs). Liquid crystals turn out to be outstanding hosts for nanomaterials. A remarkable increase in the rotational viscosity was noticed in CNT doped system as compared to silica doped same liquid crystal system. Comparison of dielectric studies shows higher value of permittivity and dielectric losses for silica-doped sample than those of CNT doped sample. The results have been interpreted both experimentally and theoretically.