Carbothermal Synthesis of Nitrogen-Doped Graphene Composites for Energy Conversion and Storage Devices

Abstract

Metal oxides and carbonaceous composites are both promising materials for electrochemical energy conversion and storage devices, such as secondary rechargeable batteries, fuel cells and electrochemical capacitors. In this study, Fe3O4 nanoparticles wrapped in nitrogen-doped (N-doped) graphene nanosheets (Fe3O4@G) were fabricated by a facile one-step carbothermal reduction method derived from Fe2O3 and liquid-polyacrylonitrile (LPAN). The unique two-dimensional structure of N-doped graphene nanosheets, can not only accommodate the volume changes during lithium intercalation/extraction processes and suppress the particles aggregation but also act as an electronically conductive matrix to improve the electrochemical performance of Fe3O4 anode, especially the rate capability. What's more, by etching Fe3O4@G to remove the iron-based oxide template, porous N-doped graphene composites (NGCs) were prepared and presented abundant pore structure with high specific surface area, delivering a specific capacitance of 172 F·g−1 at 0.5 A·g−1. In this way, Fe2O3 was both template and activator to adjust the pore size of graphene. And the effect of specific surface area and pore size tuned by the Fe2O3 activator were also revealed.

Discriminative Detection of Glutathione in Cell Lysates Based on Oxidase-Like Activity of Magnetic Nanoporous Graphene

“…By igniting, thermally stressed Fe­(OH) 3 would decompose into α-Fe 2 O 3 , which could served as template and precursor. , During the process of carbothermal reduction, GO served as the reducing agent and carbon source (C GO ). At a high reaction temperature, the bare GO in the uncovered region would be burned, while the α-Fe 2 O 3 was partially reduced to Fe 3 O 4 , resulting in the resultant products . The TEM was performed to characterize the morphological and structural features of the samples.…”

“…At a high reaction temperature, the bare GO in the uncovered region would be burned, while the α-Fe 2 O 3 was partially reduced to Fe 3 O 4 , resulting in the resultant products. 33 The TEM was performed to characterize the morphological and structural features of the samples. Figure 1B,C shows the TEM images of GO and the resultant MNPG nanocomposite after combustive treatment, respectively.…”

Progress in the application of graphene and its derivatives to osteogenesis

“…The main graphene derivatives include pristine graphene, graphene oxide (GO), reduced graphene oxide (RGO), graphene quantum dots (GQDs), graphene nanosheets, monolayers, multilayer graphene, and graphene-based nanocomposites [ 26 , 27 ]. Graphene and its derivatives have great advantages because they are low in metal impurities and do not require complex purification processes [ 28 ], and because of their high electrical conductivity, mechanical properties, and aspect ratio, they have been widely studied in many fields recently, such as water purification [ 29 , 30 ], electronics [ 31 , 32 ], sensors [ 33 , 34 ], composites [ 35 , 36 ], energy storage and conversion devices [ 37 , 38 ], and antibacterial and antibiotic membranes [ 20 , 39 ].…”

Recent advances in the design of single-atom electrocatalysts by defect engineering

“…With the increasing depletion of fossil fuels (e.g., coal, oil, and natural gas), exploiting renewable, sustainable, and eco-friendly fuels is quite urgent to alleviate the energy crisis in modern society ( Mi et al, 2018 ; Guo and Zhang, 2020 ). At present, increasing attention is being devoted to electrochemical energy conversion and storage (e.g., fuel cells, water-splitting devices, storage batteries, artificial carbon, and nitrogen fixation) due to their high energy densities and environmental benefits ( Wang et al, 2019 ; Ai et al, 2021 ; Chen et al, 2021 ).…”