Electrical conductivity, mechanical flexibility, and large electroactive surface areas are the most important factors in determining the performance of various flexible electrodes in energy storage devices. Herein, a layer-by-layer (LbL) assembly-induced metal electrodeposition approach is introduced to prepare a variety of highly porous 3D-current collectors with high flexibility, metallic conductivity, and large surface area. In this study, a few metal nanoparticle (NP) layers are LbL-assembled onto insulating paper for the preparation of conductive paper. Subsequent Ni electroplating of the metal NP-coated substrates reduces the sheet resistance from ≈103 to <0.1 Ω sq-1 while maintaining the porous structure of the pristine paper. Particularly, this approach is completely compatible with commercial electroplating processes, and thus can be directly extended to electroplating applications using a variety of other metals in addition to Ni. After depositing high-energy MnO NPs onto Ni-electroplated papers, the areal capacitance increases from 68 to 811 mF cm-2 as the mass loading of MnO NPs increases from 0.16 to 4.31 mg cm-2 . When metal NPs are periodically LbL-assembled with the MnO NPs, the areal capacitance increases to 1710 mF cm-2 .
Keywords: electrodeposition; layer-by-layer assembly; metal NP incorporation; metallic paper; textile supercapacitor electrodes.
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