Supercapacitor Properties of rGO-TiO2 Nanocomposite in Two-component Acidic Electrolyte

Abstract

The electrochemical properties of the highly porous reduced graphene oxide/titanium dioxide (rGO/TiO2) nanocomposite were studied to estimate the possibility of using it as a supercapacitor electrode. Granular aerogel rGO/TiO2 was used as an initial material for the first time of manufacturing the electrode. For the aerogel synthesis, industrial TiO2 Hombikat UV100 with a high specific surface area and anatase structure was used, and the aerogel was carried out with hydrazine vapor. Porous structure and hydrophilic–hydrophobic properties of the nanocomposite were studied with a method of standard contact porosimetry. This is important for a supercapacitor containing an aqueous electrolyte. It was found that the hydrophilic specific surface area of the nanocomposite was approximately half of the total surface area. As a result of electrochemical hydrogenation in the region of zero potential according to the scale of a standard hydrogen electrode, a reversible Faraday reaction with high recharge rate (exchange currents) was observed. The characteristic charging time of the indicated Faraday reaction does not exceed several tens of seconds, which makes it possible to consider the use of this pseudocapacitance in the systems of fast energy storage such as hybrid supercapacitors. Sufficiently high limiting pseudo-capacitance (about 1200 C/g TiO2) of the reaction was obtained.

Research Progress of Shear Thickening Electrolyte Based on Liquid–Solid Conversion Mechanism

“…It has been reported that ceramic particles play a critically vital role in various types of electrolytes [43,44]. In polymer electrolytes, adding ceramic particles such as SiO 2 [45,46], Al 2 O 3 [47], TiO 2 [48,49], and AlSi [50] can enhance ionic conductivity and prevent crystallization. Here we illustrate this process with plasmonic conductors in a fuel cell.…”

Boron Carbide as an Electrode Material: Tailoring Particle Morphology to Control Capacitive Behaviour

“…Thus, good electrically conductive materials with a high surface area are desired to achieve high capacitance values of EDLCs. In this respect, carbon-based materials with varying morphologies, such as nanosheets, nanotubes, and fibers, have been comprehensively investigated for EDLCs [ 13 , 14 , 15 , 16 , 17 ]. On the other hand, capacitance generation in pseudocapacitors are based on reversible Faradaic processes [ 18 ].…”

A highly sensitive room temperature liquefied petroleum gas (LPG) sensor with fast response based on a titanium dioxide (TiO2)–reduced graphene oxide (r-GO) composite

“…Tin oxide decorated rGO, reported by Mao et al, is one of the earliest such materials, where the sensor showed decent activity in sensing an oxidizing gas (NO 2 ) but its response was lower than that of rGO for a reducing gas such as NH 3 . 39 Coupling r-GO with TiO 2 has been a productive strategy in various applications such as photocatalysis where the sp 2 hybridized sheets act as both an electron receptor and electron transporter, thus preventing excessive recombination of photogenerated charge carriers; 33,[40][41][42] heavy ion removal where the wrinkled and squiggled sheets create efficient contact of the metal oxide nanoparticles along with preventing their agglomeration, thus enhancing their activity; 43 nitrogen fixation to NH 3 where the TiO 2 -rGO hybrid nanocomposite has a lower charge transfer resistance and faster kinetics during the electrocatalysis reaction; electrochemical sensing of ions such as nitrite 44 and hormone ingredients such as epinephrine; 45 high voltage supercapacitors; [46][47][48] antimicrobial and self-cleaning coatings of textile materials; 49 dye-sensitized solar cells where applying r-GO as an interfacial layer between the substrate and TiO 2 resulted in enhanced charge transfer and reduced carrier recombination; 50 water splitting reaction; 51 binders in cement where TiO 2 helps in the dispersibility of r-GO, 52 etc.…”