A Facile Microwave‐Assisted Method to Prepare Highly Electrosorptive Reduced Graphene Oxide/Activated Carbon Composite Electrode for Capacitive Deionization

Abstract

Reduced graphene oxide (rGO)/activated carbon (AC) composites with a hierarchically porous structure are prepared in the presence of ethylene glycol (EG) under microwave irradiation and exhibit excellent electrosorption properties. In this novel microwave‐assisted process, EG plays multiple roles such as solvent, GO reducing reagent, microwave absorber, rGO aggregation preventer, and surface wettability enhancer. In addition, the reaction system can be rapidly heated owing to the high dissipation factor of EG. As a result, GO can be rapidly reduced and in situ uniformly deposited on the AC surface. 3D porous structures can be obtained due to the explosion of the functional groups in GO. Additionally, EG causes electrostatic repulsion between the rGO layers, thereby preventing aggregation and forming a 3D hierarchical structure. Furthermore, the ethanedial that stems from oxidized ethylene glycol interacts with the graphene sheets, enhancing the wettability and conductivity of the composite electrodes, and subsequently increasing the efficiency of the charge‐transfer process. rGO/AC composites electrode fabricated using this process exhibit an outstanding electrosorption capacity of 18.6 ± 1.2 mg g−1, making them an excellent candidate for industrial applications.

Dipole moment as the underlying mechanism for enhancing the immobilization of glucose oxidase by ferrocene-chitosan for superior specificity non-invasive glucose sensing

“…The Nyquist diagrams of each electrode exhibit an incomplete semicircle in the high-frequency region, followed by a 45°-incline caused by Warburg diffusion impedance ( W 0 ). 33 In the equivalent circuit model, the equivalent series resistance ( R s ) represents the combination of the solution resistance and the internal electrode resistance, which can be reflected by the intercept at the real part of impedance ( X -axis). 34 The double-layer capacitance (CPE) is placed in parallel to a charge transfer resistance ( R ct ).…”

A Green Approach for High Oxidation Resistance, Flexible Transparent Conductive Films Based on Reduced Graphene Oxide and Copper Nanowires

“…After the CuNWs films were dipped into a solution containing the c-rGO dispersion, the CuNWs films were covered with c-rGO. However, the wrinkled c-rGO layers reveal imperfect covering on CuNWs due to the difficulty of dispersion as well as the aggregation of rGO in nature [ 23 ]. In contrast, the h-rGO layers exhibit good coverage on CuNWs film compared with the c-rGO/CuNWs film (the SEM image with low magnification of h-rGO/CuNWs is shown in Additional file 1 : Fig.…”

“…Graphene-based materials have been considered promising materials for application in flexible devices because of their good mechanical properties, high optical transparency, and prominent thermal and electrical properties [23][24][25]. Although chemical vapor deposition (CVD) enables the growth and transfer of carbon nanomaterials to various substrates and thus can achieve excellent electrical and optical properties comparable to those of ITO [26], the high energy consumption of the CVD process and inevitable damage during film transfer hinder its industrial applications, which require an economical route and scalable product [1,27].…”

Green Treatment of Phosphate from Wastewater Using a Porous Bio-Templated Graphene Oxide/MgMn-Layered Double Hydroxide Composite

“…With the rapid population growth and exacerbating chemical pollution, clean water has become a critical demand all over the world. Thus, how to develop efficient and effective technology of wastewater treatment has become one of the major challenges for scientists from various fields (Zhang et al, 2018) (Lai et al, 2019b;Li et al, 2018b;Lin et al, 2019); Liu et al (2017) (Liu et al, 2019;Wan and Chung, 2018); Phosphate is often present in wastewater due to the industrial, agricultural, and household activities and can lead to water eutrophication and endanger aquatic creatures (Ooi et al, 2017;Ren et al, 2012). There are over 90% of ecoregion rivers exceeding reference median values of total phosphorus concentration announced by the US Environmental Protection Agency and about $2.2 billion annual economic loss due to eutrophication in the US freshwaters (Dodds et al, 2009).…”