| Along with the booming of flexible/stretchable electronics that will make our life more comfortable and convenient by enabling carry-on smart applications,a pressing need for compatible micropower sources capable of conforming to curve surface and withstanding equal deformation to enable autonomy of the smart system has emerged.To keep up with that ever-increasing demand,multiple types of deformable energy storage systems have been developed to complete the entire package.As one of the promising candidates,featuring of high power density,rapid recharging capability,long cycling stability,and especially high security due to the usually employed aqueous electrolyte,stretchable supercapacitors?SCs?have attracted the attentions of many researchers.Based on this,we have designed a micro-supercapacitor with"electronic/ion dual transmission channel"structure,and further constructed a stretchable micro-supercapacitor array through the island bridge structure.The main research results of this paper are as follows:Herein,taking above-mentioned challenges into consideration,unique MXene/BC@PPy hybrid films,with rationally constructed electrons/ions dual transport channels between re-stacked few-layered MXene flakes through insertion of 1D conductive BC@PPy fibers with core-shell structure,were first designed and prepared.The demonstrated“electrons/ions dual transport channels design”delivers multiple advantages:?i?the uniformly intercalated 1D conductive core-shell structured BC@PPy fibers not only serve as interlayer scaffold to simultaneously alleviate the re-stacking of few-layered MXene sheets and guarantee more interlayer free space for the transport of ions,contributing to exposure of more active site for charge storage,but also act as nano-anchor to strengthen the bond strength between the few-layered MXene flakes,resulting in enhanced mechanical behavior of the hybrid films;?ii?most noticeable,the PPy conductive polymer shell coated on the intercalated 1D BC core fibers can act as backbones for the construction of additional electrons transport channel between propped-opened few-layered MXene sheets along the C-axis,ensuring the interlayer electrons transport and thus alleviating interlayer conductivity decline due to the insertion of interlayer spacers;?iii?the PPy conductive polymer shell serving as pseudo-capacitive active material can provide additional redox sites.As a result,profiting from the synergy enabled by the more reasonable design of morphologies,compositions,and interface structures within the MXene/BC@PPy hybrid film,concurrently realizing the regulation of interlayer conductivity,space,and bond strength,an enhanced areal capacitance of 221.21 mF·cm-2 and reinforced tensile strength of 78.9 MPa can be achieved compared to the values of pure re-stacked few-layered MXenes film(86.59 mF·cm-2/22.0 MPa).Followed a planar electrode configuration design in the MXene/BC@PPy hybrid film and introduction of islands-bridge interconnecting structure between them,MSCAs with areal capacitance/energy density up to 200.47 mF·cm-2/0.01 mWh·cm-2 and reversible level of stretchability as much as 200%elongation were further fabricated.Eventually,based on the combination of active film electrodes of high areal performance metrics,device layouts of good coplanar integration capacity,mechanical design of high deformability,and flexible printed circuit based manufacturing approaches of accuracy and ease of operation,a highly deformable integrated wearable system consisting of coplanar integrated MSCAs for deformable micropower unit,inductive coils for wireless charging unit,and commercial smart watch for functional unit were fabricated,which possesses excellent integrity,flexibility,and stretchability,and can be comfortably wearable for timing and steps counting dynamically.All the results highlight the effectiveness of demonstrated structural engineering to maximize the areal capacitance performance of re-stacked few-layered MXenes film electrodes for stretchable MSCAs with enhanced areal performance metrics toward compatible deformable energy storage in wearable electronics. |
PDF Full Text Request