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[求助]
翻译2段英语成中文
Charge storage in supercapacitors (SCs) is achieved by one or both of two main mechanisms, namely, electrical double layer (EDL) capacitance and pseudocapacitance. EDL capacitance is widely accepted to be due to electrostatic separation of electronic and ionic charges at the electrode | electrolyte interface, whilst pseudocapacitance has been broadly and ambiguously associated with fast faradaic processes which are also often termed as charge transfer or redox processes at electrode surfaces. Accordingly, SC research and development have mostly involved optimization of electrode materials to more efficiently exploit these storage mechanisms. However, in recent years, attention has been drawn to exploitation of the redox activity from the electrolyte in a bid to improve the performance of SCs.
In this vein, redox active species, such as simple and complexes of transition metal ions, halide ions, quinones, and phenylamide, have been shown to be capable of undergoing fast redox reactions on the surfaces of some carbon or metal oxide based electrode materials. These reactions can then enhance the charge storage capacity of SCs. Accordingly, electrolytes which exhibit redox activity in SCs have been classified into redox additive electrolytes in which redox active species are added to enable fast electron transfer reactions at the electrode/electrolyte interface, and redox active electrolytes which are inherently able to undergo fast electron transfer reactions. Supercapacitors are conventionally built with a separator membrane (between the two electrodes) in which the electrolyte is added. If a redox electrolyte is added to the membrane, a so called redox additive polymer electrolyte may be prepared. Nonetheless, it should be pointed out that an intrinsically redox active polymer is conducting to electrons, and hence should not be used as an electrolyte. |
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