scholarly journals Updating the Role of Reduced Graphene Oxide Ink on Field Emission Devices in Synergy with Charge Transfer Materials

Nanomaterials ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 137 ◽  
Author(s):  
Minas Stylianakis ◽  
George Viskadouros ◽  
Christos Polyzoidis ◽  
George Veisakis ◽  
George Kenanakis ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Field Emission ◽  
Large Scale ◽  
High Efficiency ◽  
Low Cost ◽  
Field Enhancement ◽  
Field Emitter ◽  
Reduced Graphene ◽  
The Impact

Hydroiodic acid (HI)-treated reduced graphene oxide (rGO) ink/conductive polymeric composites are considered as promising cold cathodes in terms of high geometrical aspect ratio and low field emission (FE) threshold devices. In this study, four simple, cost-effective, solution-processed approaches for rGO-based field effect emitters were developed, optimized, and compared; rGO layers were coated on (a) n+ doped Si substrate, (b) n+-Si/P3HT:rGO, (c) n+-Si/PCDTBT:rGO, and (d) n+-Si/PCDTBT:PC71BM:rGO composites, respectively. The fabricated emitters were optimized by tailoring the concentration ratios of their preparation and field emission characteristics. In a critical composite ratio, FE performance was remarkably improved compared to the pristine Si, as well as n+-Si/rGO field emitter. In this context, the impact of various materials, such as polymers, fullerene derivatives, as well as different solvents on rGO function reinforcement and consequently on FE performance upon rGO-based composites preparation was investigated. The field emitter consisted of n+-Si/PCDTBT:PC71BM(80%):rGO(20%)/rGO displayed a field enhancement factor of ~2850, with remarkable stability over 20 h and low turn-on field in 0.6 V/μm. High-efficiency graphene-based FE devices realization paves the way towards low-cost, large-scale electron sources development. Finally, the contribution of this hierarchical, composite film morphology was evaluated and discussed.

scholarly journals Updating the Role of Reduced Graphene Oxide Ink on Field Emission Devices in Synergy with Charge Transfer Materials

2018 ◽  
Author(s):  
Minas Stylianakis ◽  
George Viskadouros ◽  
Christos Polyzoidis ◽  
George Veisakis ◽  
George Kenanakis ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Field Emission ◽  
Large Scale ◽  
High Efficiency ◽  
Low Cost ◽  
Field Enhancement ◽  
Field Emitter ◽  
Reduced Graphene ◽  
The Impact

Hydroiodic acid (HI) treated - reduced graphene oxide (rGO) ink/conductive polymeric composites are considered as promising cold cathodes in terms of high geometrical aspect ratio and low field emission (FE) threshold devices. In this study, four simple, cost-effective, solution-processed approaches for rGO-based field effect emitters were developed, optimized and compared; rGO layers were coated on a) n+ doped Si substrate, b) n+-Si/P3HT:rGO, c) n+-Si/PCDTBT:rGO and d) n+-Si/PCDTBT:PC71BM:rGO composites, respectively. The fabricated emitters were optimized by tailoring the concentration ratios of their preparation and field emission characteristics. In a critical composite ratio, FE performance was remarkably improved compared to the pristine Si, as well as n+-Si/rGO field emitter. In this context, the impact of various materials, such as polymers, fullerene derivatives, as well as different solvents on rGO function reinforcement and consequently on FE performance upon rGO-based composites preparation was investigated. The field emitter consisted of n+-Si/PCDTBT:PC71BM(80%):rGO(20%)/rGO displayed a field enhancement factor of ∼2850, with remarkable stability over 20h and low turn-on field in 0.6V/μm. High-efficiency graphene-based FE devices realization paves the way towards low-cost, large-scale electron sources development. Finally, the contribution of this hierarchical, composite film morphology was evaluated and discussed.

scholarly journals Synthesis and Characterization of a Silver Nanoparticles-Reduced Graphene Oxide Nanohybrid by using ‘Zingiber Officinale’ Extract as a Reducing and Stabilizing Agent

2019 ◽  
Vol 7 (4.14) ◽  
pp. 498
Author(s):  
Nurul Izrini Ikhsan ◽  
Nur Farahah Jaffar
Keyword(s):  
Silver Nanoparticles ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Large Scale ◽  
Low Cost ◽  
Average Particle Size ◽  
Zingiber Officinale ◽  
Average Particle ◽  
Stabilizing Agent ◽  
Reduced Graphene

An eco-friendly solution-based chemical approach has been used to prepare silver nanoparticles-reduced graphene oxide (AgNPs-rGO) nanohybrid using Zingiber officinale extract as a reducing and stabilizing agent. The products form a stable aqueous solution without any surfactant stabilizers and hence makes it possible to produce AgNPs-rGO nanohybrid on a large scale using low-cost solution processing technique. The nanohybrid was monitored at different concentration of GO solution (0.1 mg/ml, 0.5 mg/ml and 1.0 mg/ml) and characterized using UV- visible (UV-Vis) absorption spectrum, transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy analyses. From the UV-Vis analysis, the formation of silver nanoparticles (AgNPs) was confirmed and showed a surface plasmon resonance (SPR) absorption band at 420 nm for nanohybrids with GO concentration of 0.5 mg/ml. Raman spectra shows an increase in ID/IG ratio for rGO with values of 1.007 corresponding to the concentration of GO (0.5mg/ml) as compared to GO (0.88). Completely spherical Ag nanoparticles (NPs) were found at a nanohybrid with 0.5 mg/ml of GO with an average particle size of 20 nm. The AgNPs-rGO(0.5) nanohybrid exhibit fast electron-transfer kinetics for electrochemical reaction of Fe (CN)63-/4- redox couple, suggesting the potential applications for electrocatalysis and electrochemical sensor.  

scholarly journals A Facile and Green Synthesis of a MoO2-Reduced Graphene Oxide Aerogel for Energy Storage Devices

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 594 ◽  
Author(s):  
Mara Serrapede ◽  
Marco Fontana ◽  
Arnaud Gigot ◽  
Marco Armandi ◽  
Glenda Biasotto ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Impedance ◽  
Chemical Reduction ◽  
Low Cost ◽  
Xps Analysis ◽  
3D Scaffold ◽  
Energy Storage Devices ◽  
Reduced Graphene

A simple, low cost, and “green” method of hydrothermal synthesis, based on the addition of l-ascorbic acid (l-AA) as a reducing agent, is presented in order to obtain reduced graphene oxide (rGO) and hybrid rGO-MoO2 aerogels for the fabrication of supercapacitors. The resulting high degree of chemical reduction of graphene oxide (GO), confirmed by X-Ray Photoelectron Spectroscopy (XPS) analysis, is shown to produce a better electrical double layer (EDL) capacitance, as shown by cyclic voltammetric (CV) measurements. Moreover, a good reduction yield of the carbonaceous 3D-scaffold seems to be achievable even when the precursor of molybdenum oxide is added to the pristine slurry in order to get the hybrid rGO-MoO2 compound. The pseudocapacitance contribution from the resulting embedded MoO2 microstructures, was then studied by means of CV and electrochemical impedance spectroscopy (EIS). The oxidation state of the molybdenum in the MoO2 particles embedded in the rGO aerogel was deeply studied by means of XPS analysis and valuable information on the electrochemical behavior, according to the involved redox reactions, was obtained. Finally, the increased stability of the aerogels prepared with l-AA, after charge-discharge cycling, was demonstrated and confirmed by means of Field Emission Scanning Electron Microscopy (FESEM) characterization.

scholarly journals Stable metal anodes enabled by a labile organic molecule bonded to a reduced graphene oxide aerogel

2020 ◽  
Vol 117 (48) ◽  
pp. 30135-30141
Author(s):  
Yue Gao ◽  
Daiwei Wang ◽  
Yun Kyung Shin ◽  
Zhifei Yan ◽  
Zhuo Han ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
High Efficiency ◽  
High Current Density ◽  
Solid Electrolyte Interphase ◽  
Metal Deposition ◽  
Reduced Graphene ◽  
Lithium Deposition ◽  
Reduced Graphene Oxide Aerogel ◽  
Graphene Oxide Aerogel

Metallic anodes (lithium, sodium, and zinc) are attractive for rechargeable battery technologies but are plagued by an unfavorable metal–electrolyte interface that leads to nonuniform metal deposition and an unstable solid–electrolyte interphase (SEI). Here we report the use of electrochemically labile molecules to regulate the electrochemical interface and guide even lithium deposition and a stable SEI. The molecule, benzenesulfonyl fluoride, was bonded to the surface of a reduced graphene oxide aerogel. During metal deposition, this labile molecule not only generates a metal-coordinating benzenesulfonate anion that guides homogeneous metal deposition but also contributes lithium fluoride to the SEI to improve Li surface passivation. Consequently, high-efficiency lithium deposition with a low nucleation overpotential was achieved at a high current density of 6.0 mA cm−2. A Li|LiCoO2cell had a capacity retention of 85.3% after 400 cycles, and the cell also tolerated low-temperature (−10 °C) operation without additional capacity fading. This strategy was applied to sodium and zinc anodes as well.

Nitrogen/sulfur dual-doped reduced graphene oxide supported CuFeS2 as an efficient electrocatalyst for the oxygen reduction reaction

2018 ◽  
Vol 42 (3) ◽  
pp. 2081-2088 ◽  
Author(s):  
Man Zhang ◽  
Wei Hong ◽  
Ruinan Xue ◽  
Lingzhi Li ◽  
Guanbo Huang ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Fuel Cells ◽  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Reduced Graphene Oxide ◽  
Low Cost ◽  
Reduction Reaction ◽  
Reduced Graphene

At present, low-cost and efficient electrocatalysts for accelerating the oxygen reduction reaction in fuel cells are highly desired.

Sign in / Sign up

Export Citation Format

Share Document