Electrospun Core–Shell Nanofibrous Membranes with Nanocellulose-Stabilized Carbon Nanotubes for Use as High-Performance Flexible Supercapacitor Electrodes with Enhanced Water Resistance, Thermal Stability, and Mechanical Toughness

Abstract

A high-performance flexible supercapacitor electrode with a core–shell structure is successfully developed from cellulose nanocrystal (CNC)-stabilized carbon nanotubes (CNTs). By incorporating poly­(vinyl alcohol) (PVA) and poly­(acrylic acid) (PAA), a cross-linked nanofibrous membrane (CNT–CNC/PVA–PAA) is prepared as the core material via directional electrospinning, followed by a thermal treatment. The flexible supercapacitor electrodes are eventually fabricated via the in situ polymerization of polyaniline (PANI), which was used as the coating shell material, on the aligned electrospun nanofibers. By taking advantage of the thermally induced esterification cross-linking that occurs among PVA, PAA, and the CNT–CNC nanohybrids, the membranes present with enhanced water resistance, mechanical strength, and thermal stability. After the surface coating of the PANI shell, the optimized PANI@CNT–CNC/PVA–PAA nanofibrous membranes exhibit a large porosity, an enhanced specific surface area, a superior tensile strength of ∼54.8 MPa, and a favorable electroconductivity of ∼0.44 S m–1. As expected, the nanofibrous electrodes with a specific capacitance of 164.6 F g–1 can maintain 91% of the original capacitance after 2000 cycles. The symmetrical solid-state supercapacitor assembled by the nanofibrous electrodes shows an excellent capacitance of 155.5 F g–1 and a remarkable capacitance retention of 92, 90, and 89% after 2000 cycles under flat, bending, and twisting deformations, respectively.

Investigation of Synthesis Mechanism, Optimal Hot-Pressing Conditions, and Curing Behavior of Sucrose and Ammonium Dihydrogen Phosphate Adhesive

“…Due to decreasing fossil fuel resources and rapidly increasing environmental awareness, the utilization of renewable resources has become a focus of materials science research [1][2][3][4]. As a consequence, many novel bio-based materials have been developed and are expected to be utilized in many fields [5][6][7][8][9][10]. Wood-based materials (such as particleboard [11], plywood [12], oriented strand board [13], and fiberboard [14]) are common in everyday living environments, and are typically fabricated using formaldehyde-based resins to obtain excellent bonding performance [15][16][17].…”

Applications of Nanocellulose/Nanocarbon Composites: Focus on Biotechnology and Medicine

“…Other flexible 3D supercapacitor devices were fabricated by incorporating polypyrrole nanofibers, polypyrrole-coated CNTs, and manganese dioxide (MnO 2 ) nanoparticles in chemically cross-linked cellulose nanocrystal aerogels [145]. Electrospun core-shell nanofibrous membranes, containing CNTs stabilized with cellulose nanocrystals, were developed for use as high-performance flexible supercapacitor electrodes with enhanced water resistance, thermal stability and mechanical toughness [40]. Electrodes for lithium batteries were based on freestanding LiCoO 2 /MWCNT/cellulose nanofibril composites, fabricated by a vacuum filtration technique [148], or on freestanding CNT-nanocrystalline cellulose composite films [41].…”

Electrospun Functional Materials toward Food Packaging Applications: A Review

“…Electrospinning is a versatile technique for continuously producing nanofibers with a fiber diameter range from sub-nanometers to micrometers. The electrospun fibers have been broadly applied in nearly all the fields, such as composites [1][2][3][4][5], tissue engineering [6][7][8][9], biomaterials [10,11], energy storage and conversion [12][13][14][15][16], food packaging [17][18][19], drug deliver and release [20,21], catalysts [22][23][24][25], sensors [26][27][28][29], flexible electronics [30][31][32], reactors [33,34], environmental protection [35][36][37], etc. During the fiber preparation process, the polymer solution or melt is induced by a high-voltage power supply device to accelerate injection onto a collecting plate with opposite polarity to form nanofiber membrane.…”