All-solid-state high-energy planar hybrid micro-supercapacitors based on 2D VN nanosheets and Co(OH)2 nanoflowers

Abstract

Planar micro-supercapacitors are recognized as one of the most competitive on-chip power sources for integrated electronics. However, most reported symmetric micro-supercapacitors suffer from low energy density. Herein, we demonstrate the facile maskassisted fabrication of new-type all-solid-state planar hybrid micro-supercapacitors with high energy density, based on interdigital patterned films of porous vanadium nitride nanosheets as negative electrode and Co(OH) 2 nanoflowers as positive electrode. The resultant planar hybrid micro-supercapacitors display high areal capacitance of 21 mF cm −2 and volumetric capacitance of 39.7 F cm −3 at 0.2 mA cm −2 , and exhibit remarkable energy density of 12.4 mWh cm −3 and power density of 1750 mW cm −3 , based on the whole device, outperforming most reported planar hybrid micro-supercapacitors and planar asymmetric micro-supercapacitors. Moreover, all-solid-state planar hybrid micro-supercapacitors show excellent cyclability with 84% capacitance retention after 10000 cycles, and exceptionally mechanical flexibility. Therefore, our proposed strategy for the simplified construction of planar hybrid micro-supercapacitors will offer numerous opportunities of utilizing graphene and other 2D nanosheets for high-energy microscale supercapacitors for electronics.

General Interfacial Self‐Assembly Engineering for Patterning Two‐Dimensional Polymers with Cylindrical Mesopores on Graphene

“…Moreover, PPy has high pseudocapacitance from adjustable redox activity when serving as supercapacitor electrodes. In light of these merits, we selected mPPy/rGO nanosheets as interdigital microelectrode materials to assemble flexible planar MSCs (denoted as mPPy/rGO‐MSCs) on a nylon membrane with the help of mask‐assisted filtration, and examined their electrochemical performance in H 2 SO 4 /polyvinyl alcohol (PVA) gel electrolyte. Notably, the resultant interdigital mPPy/rGO microelectrodes present remarkable uniformity, large‐area continuity, and outstanding mechanical flexibility, with a valid electrode area of 1.12 cm 2 (Figure b).…”

Asymmetric Pseudocapacitors Based on Interfacial Engineering of Vanadium Nitride Hybrids

“…Generally, to enhance the storage performance of VN, strategies such as nanostructuring [ 18 , 19 , 20 , 21 ] and hybridization [ 22 , 23 , 24 ] have been employed. The hybridization approach involves carbon-based hybrids [ 21 , 25 , 26 ] and carbon-free hybrids [ 27 , 28 ].…”

Hierarchical Ordered Dual‐Mesoporous Polypyrrole/Graphene Nanosheets as Bi‐Functional Active Materials for High‐Performance Planar Integrated System of Micro‐Supercapacitor and Gas Sensor

“…To evaluate the potential of DM‐PG nanosheets for practical energy storage, we further employ 2D DM‐PG as interdigital microelectrodes to construct all‐solid‐state planar DM‐PG MSC using a mask‐assisted deposition technique, [ 50–53 ] with the assistance of electrochemically exfoliated graphene (EG) as metal‐free current collector, [ 54–56 ] carbon nanotube (CNT) as conductive additive, and polyvinyl alcohol (PVA)/H 2 SO 4 gel as electrolyte ( Figure a; Figure S15, Supporting Information). It is noted that the addition of CNT into microelectrodes can guarantee large‐area continuity, robust mechanical flexibility, and high performance (Figures S16 and S17, Supporting Information).…”