scholarly journals Conductive Biomass Films Containing Graphene Oxide and Cationic Cellulose Nanofibers for Electric-Heating Applications

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1187
Author(s):  
Shanqing Liang ◽  
Huicong Wang ◽  
Xin Tao
Keyword(s):  
Thermal Stability ◽  
Graphene Oxide ◽  
Low Voltage ◽  
Cellulose Nanofibers ◽  
Electric Heating ◽  
Heating Cycle ◽  
Ultrasonic Dispersion ◽  
Degradation Temperature ◽  
Potential Applications ◽  
Safety Limit

A low-voltage biomass matrix and flexible electric-heating composite with graphene oxide (GO) and cationic cellulose nanofiber (CCNF) were fabricated by ultrasonic dispersion and suction filtration. The main results show that the tensile strength and strain of the films decreased with an increase in the GO content, but the thermal stability increased. The GO/CCNF film underwent rapid thermal decomposition at 250–350 °C, and the maximum degradation temperature was higher by 19 °C compared to that of the pure CCNF film. It was found that the electrical conductivity increased from 0.013 to 2.96 S/cm with an increase in the GO content from 20 to 60 wt%, resulting in an increase in the power density from 122 to 2456 W/m2. The films could rapidly attain the temperature within 50 s, and the heat transferred by radiation and convection was 21.62 mW/°C, thereby exhibiting excellent electric heating response. Moreover, the film demonstrated a stable electric-heating cycle after a 12.5 h cycling test and meets the requirements of low-temperature electric heating products under the 36 V electric safety limit, which expands the potential applications of biomass-derived cellulose nanofibers.

scholarly journals Extraordinary thermal behavior of graphene oxide in air for electrode applications

2021 ◽  
Author(s):  
Joong Tark Han ◽  
Joon Young Cho ◽  
Jeong Hoon Kim
Keyword(s):  
Thermal Stability ◽  
Graphene Oxide ◽  
Physical Properties ◽  
Thermal Behavior ◽  
Stability Of Solution ◽  
Exfoliated Graphene ◽  
Potential Applications ◽  
Thermal Stability Of

The thermal stability of solution-exfoliated graphene oxide (GO) in air is one of the most important physical properties influencing its potential applications. To date, majority of the GO prepared by...

scholarly journals Adamantane-Modified Graphene Oxide for Cyanate Ester Resin Composites with Improved Properties

2019 ◽  
Vol 9 (5) ◽  
pp. 881 ◽  
Author(s):  
Zhicong Miao ◽  
Juntao Shi ◽  
Tianjiao Liu ◽  
Peng Li ◽  
Zhiqiang Su ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Dielectric Constant ◽  
Graphene Oxide ◽  
Interfacial Polarization ◽  
Cyanate Ester ◽  
Scanning Calorimetry ◽  
Modified Graphene Oxide ◽  
Potential Applications ◽  
Cure Temperature ◽  
Modified Graphene

The conjugation of graphene and polymers has attracted great attention for the fabrication of functional hybrid nanomaterials. Here, we demonstrate the modification of graphene oxide (GO) with adamantane (AMT) through the diimide-activated amidation reaction. The modification of GO with AMT improves the dispersion and decreases the interfacial polarization of GO, causing a lower dielectric constant for the fabricated GO/AMT hybrid materials. The structures of GO/AMT were studied by Fourier transform infrared spectroscopy and Raman spectroscopy. Furthermore, the mechanical properties, thermal stability, and dielectric constant of GO/AMT composites were measured at a low cured temperature using various techniques, such as differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical thermal analysis. It was found that the synthesized GO/AMT materials with different contents were blended into cyanate ester (CE) resins, resulting in a lower cure temperature, smaller dielectric constant, higher thermal stability, and stronger water resistance. It is expected that this novel GO/AMT-CE material will have potential applications for replacing traditional thermosetting resins.

scholarly journals Lerf–Klinowski-type models of graphene oxide and reduced graphene oxide are robust in analyzing non-covalent functionalization with porphyrins

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alexandra Siklitskaya ◽  
Ewelina Gacka ◽  
Daria Larowska ◽  
Marta Mazurkiewicz-Pawlicka ◽  
Artur Malolepszy ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Excited States ◽  
Reduced Graphene ◽  
Simulation Protocol ◽  
Potential Applications ◽  
H 26 ◽  
High Level ◽  
Experimental And Theoretical Studies ◽  
Low Solubility

AbstractGraphene-based nanohybrids are good candidates for various applications. However, graphene exhibits some unwanted features such as low solubility in an aqueous solution or tendency to aggregate, limiting its potential applications. On the contrary, its derivatives, such as graphene oxide (GO) and reduced graphene oxide (RGO), have excellent properties and can be easily produced in large quantities. GO/RGO nanohybrids with porphyrins were shown to possess great potential in the field of photocatalytic hydrogen production, pollutant photodegradation, optical sensing, or drug delivery. Despite the rapid progress in experimental research on the porphyrin-graphene hybrids some fundamental questions about the structures and the interaction between components in these systems still remain open. In this work, we combine detailed experimental and theoretical studies to investigate the nature of the interaction between the GO/RGO and two metal-free porphyrins 5,10,15,20-tetrakis(4-aminophenyl) porphyrin (TAPP) and 5,10,15,20-tetrakis(4-hydroxyphenyl) porphyrin (TPPH)]. The two porphyrins form stable nanohybrids with GO/RGO support, although both porphyrins exhibited a slightly higher affinity to RGO. We validated finite, Lerf–Klinowski-type (Lerf et al. in J Phys Chem B 102:4477, 1998) structural models of GO ($$\hbox {C}_{59}\hbox {O}_{26}\hbox {H}_{26}$$ C 59 O 26 H 26 ) and RGO ($$\hbox {C}_{59}\hbox {O}_{17}\hbox {H}_{26}$$ C 59 O 17 H 26 ) and successfully used them in ab initio absorption spectra simulations to track back the origin of experimentally observed spectral features. We also investigated the nature of low-lying excited states with high-level wavefunction-based methods and shown that states’ density becomes denser upon nanohybrid formation. The studied nanohybrids are non-emissive, and our study suggests that this is due to excited states that gain significant charge-transfer character. The presented efficient simulation protocol may ease the properties screening of new GO/RGO-nanohybrids.

scholarly journals Facile Synthesis and Characterization of Palm CNF-ZnO Nanocomposites with Antibacterial and Reinforcing Properties

2021 ◽  
Vol 22 (11) ◽  
pp. 5781
Author(s):  
Janarthanan Supramaniam ◽  
Darren Yi Sern Low ◽  
See Kiat Wong ◽  
Loh Teng Hern Tan ◽  
Bey Fen Leo ◽  
...  
Keyword(s):  
Plant Biomass ◽  
Cellulose Nanofibers ◽  
High Strength ◽  
Salmonella Typhi ◽  
Particle Sizes ◽  
Mechanical Reinforcement ◽  
Uniform Size ◽  
Preparation Methods ◽  
Potential Applications

Cellulose nanofibers (CNF) isolated from plant biomass have attracted considerable interests in polymer engineering. The limitations associated with CNF-based nanocomposites are often linked to the time-consuming preparation methods and lack of desired surface functionalities. Herein, we demonstrate the feasibility of preparing a multifunctional CNF-zinc oxide (CNF-ZnO) nanocomposite with dual antibacterial and reinforcing properties via a facile and efficient ultrasound route. We characterized and examined the antibacterial and mechanical reinforcement performances of our ultrasonically induced nanocomposite. Based on our electron microscopy analyses, the ZnO deposited onto the nanofibrous network had a flake-like morphology with particle sizes ranging between 21 to 34 nm. pH levels between 8–10 led to the formation of ultrafine ZnO particles with a uniform size distribution. The resultant CNF-ZnO composite showed improved thermal stability compared to pure CNF. The composite showed potent inhibitory activities against Gram-positive (methicillin-resistant Staphylococcus aureus (MRSA)) and Gram-negative Salmonella typhi (S. typhi) bacteria. A CNF-ZnO-reinforced natural rubber (NR/CNF-ZnO) composite film, which was produced via latex mixing and casting methods, exhibited up to 42% improvement in tensile strength compared with the neat NR. The findings of this study suggest that ultrasonically-synthesized palm CNF-ZnO nanocomposites could find potential applications in the biomedical field and in the development of high strength rubber composites.

Concisely modularized assembling of graphene-based thin films with promising electrode performance

2019 ◽  
Vol 3 (7) ◽  
pp. 1462-1470 ◽  
Author(s):  
Weiwei Wei ◽  
Rohit L. Vekariy ◽  
Chuanting You ◽  
Yafei He ◽  
Ping Liu ◽  
...  
Keyword(s):  
Thin Films ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Double Layer ◽  
Van Der Waals ◽  
Cellulose Nanofibers ◽  
Van Der Waals Interactions ◽  
Electrode Performance ◽  
Reduced Graphene

Highly dense thin films assembled from cellulose nanofibers and reduced graphene oxide via van der Waals interactions to realize ultrahigh volumetric double-layer capacitances.

scholarly journals The Structure–Properties–Cytotoxicity Interplay: A Crucial Pathway to Determining Graphene Oxide Biocompatibility

2021 ◽  
Vol 22 (10) ◽  
pp. 5401
Author(s):  
Marta Dziewięcka ◽  
Mirosława Pawlyta ◽  
Łukasz Majchrzycki ◽  
Katarzyna Balin ◽  
Sylwia Barteczko ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Defense Mechanisms ◽  
Physicochemical Analysis ◽  
Experimental Models ◽  
Acheta Domesticus ◽  
Synthesis Process ◽  
Synthesis Methods ◽  
Toxicity Potential ◽  
Potential Applications

Interest in graphene oxide nature and potential applications (especially nanocarriers) has resulted in numerous studies, but the results do not lead to clear conclusions. In this paper, graphene oxide is obtained by multiple synthesis methods and generally characterized. The mechanism of GO interaction with the organism is hard to summarize due to its high chemical activity and variability during the synthesis process and in biological buffers’ environments. When assessing the biocompatibility of GO, it is necessary to take into account many factors derived from nanoparticles (structure, morphology, chemical composition) and the organism (species, defense mechanisms, adaptation). This research aims to determine and compare the in vivo toxicity potential of GO samples from various manufacturers. Each GO sample is analyzed in two concentrations and applied with food. The physiological reactions of an easy model Acheta domesticus (cell viability, apoptosis, oxidative defense, DNA damage) during ten-day lasting exposure were observed. This study emphasizes the variability of the GO nature and complements the biocompatibility aspect, especially in the context of various GO-based experimental models. Changes in the cell biomarkers are discussed in light of detailed physicochemical analysis.

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