Chinese ink-facilitated fabrication of paper-based composites as electrodes for supercapacitors

Abstract

Commercial Chinese ink was employed to disperse pristine vapor-grown carbon nanofibers (VGCNFs) in aqueous suspensions via horizontal ball milling. The obtained suspension was used to fabricate conductive paper-based composites through filtration-deposition onto filter paper. It was found that the carbon black particles from the Chinese ink helped separate VGCNFs and acted as connection points between the VGCNFs, while the glue reinforced the conduction network. Thus, the VGCNF-ink/paper ternary composite showed sufficiently low sheet resistance. With merely 2.5 mg•cm −2 VGCNFs, the sheet resistance could be reduced to 4.5 Ω•sq −1 . As a proof of concept, these paper-based composites were directly used as electrodes of solid-state symmetric electronic double-layer capacitors (EDLCs) and the substrate for the electrodeposition of MnO 2 to achieve higher electrochemical performances. The EDLCs fabricated with 2.5 mg•cm −2 VGCNFs showed a specific capacitance of 224 mF•cm −2 at a current density of 1 mA•cm −2 , which was retained by 86.4% after 10,000 charge-discharge cycles. Moreover, thanks to the high electrical conductivity and the porous structure, the MnO 2 decorated paper-based composites exhibited dramatically enhanced specific capacitance. It is believed that our finding offers an idea to directly utilize commercial Chinese ink for the fabrication of electrode materials.

Environmentally Friendly and Self-Healable Supercapacitors Realized by a NaCl-Penetrable Polyampholyte Conductive Hydrogel

“…The recent development of flexible and wearable electronics potentially accelerates the interest in researching stretchable energy storage devices including supercapacitor and batteries. − Among them, flexible supercapacitors are well developed due to their high specific capacitance, remarkable power density, fast charging/discharging rate, and good flexibility. − So far, many schemes have been designed to improve the flexibility of supercapacitors, such as coaxial, spring, and spine hinged in one-dimension, wave and Z-shaped in two-dimension, and honeycomb, origami, and paper cutout in three-dimension. − However, a flexible supercapacitor embedded in wearable electronics is often subjected to complex and unpredictable stress, leading to structure fracture, mechanical damage, and function failure. These failures would seriously limit the reliability and lifetime of supercapacitors, bringing about the whole scale breakdown of the electronic devices, generation of abundant electronic waste, and safety hazards. , Thus, an ideal supercapacitor should not only possess excellent electrochemical and portable characteristics but also be endowed with additionally functional characters such as self-healing of electrode material collapse or devices’ configuration integrity, and electrical properties’ degradation as well as environmental friendliness.…”

Preparation of MXene-based hybrids and their application in neuromorphic devices

“…Two-dimensional (2D) nanomaterials are likely to emerge as potential candidates for neuromorphic device applications due to their atomic-scale thickness, abundant surface information, and distinctive physical and chemical properties [13][14][15][16][17]. In contrast to those made of traditional metal oxides, memristors with 2D nanomaterials are strongly flexible and require less power [18][19][20][21][22]. Moreover, 2D nanomaterials could be stacked through molecular interaction to obtain properties beyond the pristine components [23][24][25].…”

Microchannel‐Confined Chinese Ink‐Based Highly Stretchable Liquid‐State Strain Sensor for Early Warning of Road Collapse

“…[38][39][40] Recently, there has been a growing interest in exploring the potential properties of Chinese ink. However, most of research has primarily focused on utilizing Chinese ink as a coating material to enhance the electrical conductivity of supporting materials, [41][42][43] few studies have considered its application as a functional conductive material. Nevertheless, due to its inher-ent high conductive stability, fluidity, and environmental friendly, Chinese ink could be a suitable functional material that aligns well with the aforementioned scene above for underground cavity monitoring.…”