To address the problem of small specific capacitance

large self-noise

and weak electric field response and of carbon fiber(CF)electrodes

a novel ordered mesoporous carbon coated CF(OMC/CF)composite electrode is prepared by the high temperature carbonization of the phenolic resin-block copolymer(Resol-F127)film

which is co-assembly formed on the surface CF.The OMC exhibits a two-dimensional hexagonal arrangement with a pore size of about 16nm

which greatly increases the specific surface area of the composite electrode

promoting the increase of high specific capacitance(37.1F/g)and the reduction of

charge transfer resistance and capacitive reactance.In terms of electric field response

the coated OMC is beneficial to improve the response to low-frequency electric field range of 0.01~1Hz

obtaining the improvement of waveform signal response in the accuracy

sensitivity and linearity and the electrode self-noise can be reduced to 0.73nV/Hz

1/2

@1Hz

which is conducive to the detection of weak low-frequency signals underwater.The preparation of the OMC/CF composite electrode provides a new approach for the innovative development of high-performance marine electric field electrodes with high sensitivity and low self-noise.