Flexible and micro-sized energy conversion/storage components are extremely demanding in portable and multifunctional electronic devices, especially those small,flexible, roll-up and even wearable ones. Here in this p...Flexible and micro-sized energy conversion/storage components are extremely demanding in portable and multifunctional electronic devices, especially those small,flexible, roll-up and even wearable ones. Here in this paper, a two-step electrochemical deposition method has been developed to coat Ni fibers with reduced graphene oxide and MnO2 subsequently, giving rise to Ni@reduced-graphene-oxide@MnO2 sheath-core flexible electrode with a high areal specific capacitance of 119.4 mF cm^-2 at a current density of 0.5 mA cm^-2 in 1 mol L^-1 Na2SO4 electrolyte. Using polyvinyl alcohol（PVA）-LiCl as a solid state electrolyte, two Ni@reduced-grapheneoxide@Mn02 flexible electrodes were assembled into a freestanding, lightweight, symmetrical fiber-shaped micro-supercapacitor device with a maximum areal capacitance of26.9 mF cm^-2. A high power density of 0.1 W cm^-3 could be obtained when the energy density was as high as0.27 mW h cm^-3. Moreover, the resulting micro-supercapacitor device also demonstrated good flexibility and high cyclic stability. The present work provides a simple, facile and low-cost method for the fabrication of flexible, lightweight and wearable energy conversion/storage micro-devices with a high-performance.展开更多
A novel all-solid-state, coaxial, fiber-shaped asymmetric supercapacitor has been fabricated by wrapping a conducting carbon paper on a MnO2-modified nanoporous gold wire. This energy wire exhibits high capacitance of...A novel all-solid-state, coaxial, fiber-shaped asymmetric supercapacitor has been fabricated by wrapping a conducting carbon paper on a MnO2-modified nanoporous gold wire. This energy wire exhibits high capacitance of 12 mF.cm^-2 and energy density of 5.4 μW.h.cm^-2 with excellent cycling stability. Hierarchical nanostructures and coaxial architectural design facilitate effective contacts between the two core@sheath electrodes and active layers with high flexibility and high performance. This work provides the first example of coaxial fiber- shaped asymmetric supercapacitors with an operation voltage of 1.8 V, and holds great potential for future flexible electronic devices.展开更多
High volumetric specific capacitance is essential for flexible supercapacitors.In this paper,a flexible composite electrode with ultrahigh volumetric specific capacitance and good rate performance is designed and prep...High volumetric specific capacitance is essential for flexible supercapacitors.In this paper,a flexible composite electrode with ultrahigh volumetric specific capacitance and good rate performance is designed and prepared.The film electrode is composed of non-porous compact polyaniline as the matrix and a small amount of reduced graphene oxide sheets as the conductive filler.The film is prepared by a newly developed solution casting method,where the casting solution is obtained by self-assembly of polyaniline and graphene oxide in a blended solution.A systematical investigation on the effect of reduced graphene oxide sheets reveals that they serve as both the conductive filler and the diffusion barrier.With the optimized reduced graphene oxide content,a large volumetric specific capacitance of 1354 F cm^−3 at 2.4 A cm^−3 is achieved,and good rate performance is also obtained because of the good ionic conductivity of polyaniline.This work provides a high performance electrode for flexible supercapacitors,and the solution casting method is also valuable in fabricating other organic electrode materials.展开更多
基金supported by the Ministry of Education of China (IRT1148)the National Natural Science Foundation of China (51772157 and 21173116)+3 种基金Synergistic Innovation Center for Organic Electronics and Information Displays,Jiangsu Province "Six Talent Peak" (2015-JY-015)Jiangsu Provincial Natural Science Foundation (BK20141424)the Program of Nanjing University of Posts and Telecommunications (NY214088)the Open Research Fund of State Key Laboratory of Bioelectronics of Southeast University (12015010)
文摘Flexible and micro-sized energy conversion/storage components are extremely demanding in portable and multifunctional electronic devices, especially those small,flexible, roll-up and even wearable ones. Here in this paper, a two-step electrochemical deposition method has been developed to coat Ni fibers with reduced graphene oxide and MnO2 subsequently, giving rise to Ni@reduced-graphene-oxide@MnO2 sheath-core flexible electrode with a high areal specific capacitance of 119.4 mF cm^-2 at a current density of 0.5 mA cm^-2 in 1 mol L^-1 Na2SO4 electrolyte. Using polyvinyl alcohol（PVA）-LiCl as a solid state electrolyte, two Ni@reduced-grapheneoxide@Mn02 flexible electrodes were assembled into a freestanding, lightweight, symmetrical fiber-shaped micro-supercapacitor device with a maximum areal capacitance of26.9 mF cm^-2. A high power density of 0.1 W cm^-3 could be obtained when the energy density was as high as0.27 mW h cm^-3. Moreover, the resulting micro-supercapacitor device also demonstrated good flexibility and high cyclic stability. The present work provides a simple, facile and low-cost method for the fabrication of flexible, lightweight and wearable energy conversion/storage micro-devices with a high-performance.
文摘A novel all-solid-state, coaxial, fiber-shaped asymmetric supercapacitor has been fabricated by wrapping a conducting carbon paper on a MnO2-modified nanoporous gold wire. This energy wire exhibits high capacitance of 12 mF.cm^-2 and energy density of 5.4 μW.h.cm^-2 with excellent cycling stability. Hierarchical nanostructures and coaxial architectural design facilitate effective contacts between the two core@sheath electrodes and active layers with high flexibility and high performance. This work provides the first example of coaxial fiber- shaped asymmetric supercapacitors with an operation voltage of 1.8 V, and holds great potential for future flexible electronic devices.
基金financially supported by the National Natural Science Foundation of China (21774104 and 21975210)the Natural Science Foundation of Fujian Province (2018J06015)
文摘High volumetric specific capacitance is essential for flexible supercapacitors.In this paper,a flexible composite electrode with ultrahigh volumetric specific capacitance and good rate performance is designed and prepared.The film electrode is composed of non-porous compact polyaniline as the matrix and a small amount of reduced graphene oxide sheets as the conductive filler.The film is prepared by a newly developed solution casting method,where the casting solution is obtained by self-assembly of polyaniline and graphene oxide in a blended solution.A systematical investigation on the effect of reduced graphene oxide sheets reveals that they serve as both the conductive filler and the diffusion barrier.With the optimized reduced graphene oxide content,a large volumetric specific capacitance of 1354 F cm^−3 at 2.4 A cm^−3 is achieved,and good rate performance is also obtained because of the good ionic conductivity of polyaniline.This work provides a high performance electrode for flexible supercapacitors,and the solution casting method is also valuable in fabricating other organic electrode materials.
