Electrochemically Tuned Properties for Electrolyte‐Free Carbon Nanotube Sheets

Abstract

Injecting high electronic charge densities can profoundly change the optical, electrical, and magnetic properties of materials. Such charge injection in bulk materials has traditionally involved either dopant intercalation or the maintained use of a contacting electrolyte. Tunable electrochemical charge injection and charge retention, in which neither volumetric intercalation of ions nor maintained electrolyte contact is needed, are demonstrated for carbon nanotube sheets in the absence of an applied field. The tunability of electrical conductivity and electron field emission in the subsequent material is presented. Application of this material to supercapacitors may extend their charge‐storage times because they can retain charge after the removal of the electrolyte.

Structural and electrochemical investigation of waste newspaper based electrodes for supercapacitor applications

“…While, sub-merged in 1 M H 3 PO 4 electrolyte, a 0.7 V (vs. SCE) constant potential was applied for 500 s, after which the electrode was immediately removed from the electrolyte. Zakhidov et al [36] showed that high double-layer charge densities can be retained after removing the sample from their electrolytes.…”

Macroscopic Carbon Nanotube Assemblies: Preparation, Properties, and Potential Applications

“…With the help of simple solution‐processing (e.g., conformal coating, dipping, and drying), Hu et al have successfully fabricated CNT‐based commercial paper or textile energy devices (Figure 6g,h), which will bring new opportunities for advanced applications in energy storage and conversion 66–68. In addition, the CNT‐sheet supercapacitors are able to retain charge in the absence of contacting electrolyte, which greatly extends their charge‐storage times and is of significant importance in various applications 142. Nevertheless, different from the promising applications of transparent CNT films prepared through the solution‐processing and/or printing procedures described above, it is important to note that the potentials of CNT films fabricated by the direct CVD approach in the electronics and optoelectronics fields are still on the way.…”

Binder-free composite electrodes using carbon nanotube networks as a host matrix for activated carbon microparticles

“…8. This could be due to the so-called 'electrochemical doping' of the SWNTs at higher potentials [15,16]. The composite electrode fabricated using the host CNT network concept showed a similar rectangular shape with a higher specific capacitance provided by the high surface area aC particles.…”