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1.
Small ; : e2403656, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38818675

ABSTRACT

Monolayer boron nanosheet, commonly known as borophene, has garnered significant attention in recent years due to its unique structural, electronic, mechanical, and thermal properties. This review paper provides a comprehensive overview of the advancements in the synthetic strategies, tunable properties, and prospective applications of borophene, specifically focusing on its potential in energy storage devices. The review begins by discussing the various synthesis techniques for borophene, including molecular beam epitaxy (MBE), chemical vapor deposition (CVD), and chemical methods, such as ultrasonic exfoliation and thermal decomposition of boron-containing precursors. The tunable properties of borophene, including its electronic, mechanical, and thermal characteristics, are extensively reviewed, with discussions on its bandgap engineering, plasmonic behavior, and thermal conductivity. Moreover, the potential applications of borophene in energy storage devices, particularly as anode materials in metal-ion batteries and supercapacitors, along with its prospects in other energy storage systems, such as sodium-oxygen batteries, are succinctly, discussed. Hence, this review provides valuable insights into the synthesis, properties, and applications of borophene, offering much-desired guidance for further research and development in this promising area of nanomaterials science.

2.
Polymers (Basel) ; 15(10)2023 May 12.
Article in English | MEDLINE | ID: mdl-37242851

ABSTRACT

Energy storage is one of the challenges currently confronting the energy sector. However, the invention of supercapacitors has transformed the sector. This modern technology's high energy capacity, reliable supply with minimal lag time, and extended lifetime of supercapacitors have piqued the interest of scientists, and several investigations have been conducted to improve their development. However, there is room for improvement. Consequently, this review presents an up-to-date investigation of different supercapacitor technologies' components, operating techniques, potential applications, technical difficulties, benefits, and drawbacks. In addition, it thoroughly highlights the active materials used to produce supercapacitors. The significance of incorporating every component (electrode and electrolyte), their synthesis approach, and their electrochemical characteristics are outlined. The research further examines supercapacitors' potential in the next era of energy technology. Finally, concerns and new research prospects in hybrid supercapacitor-based energy applications that are envisaged to result in the development of ground-breaking devices, are highlighted.

3.
ACS Omega ; 7(44): 39498-39519, 2022 Nov 08.
Article in English | MEDLINE | ID: mdl-36385802

ABSTRACT

The atomically thick two-dimensional (2D) materials are at the forefront of revolutionary technologies for energy storage devices. Due to their fascinating physical and chemical features, these materials have gotten a lot of attention. They are particularly appealing for a wide range of applications, including electrochemical storage systems, due to their simplicity of property tuning. The MXene is a type of 2D material that is widely recognized for its exceptional electrochemical characteristics. The use of these materials in conjunction with conducting polymers, notably polypyrrole (PPy), has opened new possibilities for lightweight, flexible, and portable electrodes. Therefore, herein we report a comprehensive review of recent achievements in the production of MXene/PPy nanocomposites. The structural-property relationship of this class of nanocomposites was taken into consideration with an elaborate discussion of the various characterizations employed. As a result, this research gives a narrative explanation of how PPy interacts with distinct MXenes to produce desirable high-performance nanocomposites. The effects of MXene incorporation on the thermal, electrical, and electrochemical characteristics of the resultant nanocomposites were discussed. Finally, it is critically reviewed and presented as an advanced composite material in electrochemical storage devices, energy conversion, electrochemical sensors, and electromagnetic interference shielding.

4.
ACS Omega ; 7(38): 33808-33820, 2022 Sep 27.
Article in English | MEDLINE | ID: mdl-36188269

ABSTRACT

In this paper, density functional theory (DFT) simulations are used to evaluate the possible use of a graphene oxide-based poly(ethylene glycol) (GO/PEG) nanocomposite as a drug delivery substrate for cephalexin (CEX), an antibiotic drug employed to treat wound infection. First, the stable configuration of the PEGylated system was generated with a binding energy of -25.67 kcal/mol at 1.62 Å through Monte Carlo simulation and DFT calculation for a favorable adsorption site. The most stable configuration shows that PEG interacts with GO through hydrogen bonding of the oxygen atom on the hydroxyl group of PEG with the hydrogen atom of the carboxylic group on GO. Similarly, for the interaction of the CEX drug with the GO/PEG nanocomposite excipient system, the adsorption energies are computed after determining the optimal and thermodynamically favorable configuration. The nitrogen atom from the amine group of the drug binds with a hydrogen atom from the carboxylic group of the GO/PEG nanocomposite at 1.75 Å, with an adsorption energy of -36.17 kcal/mol, in the most stable drug-excipient system. Drug release for tissue regeneration at the predicted target cell is more rapid in moist conditions than in the gas phase. The solubility of the suggested drug in the aqueous media around the open wound is shown by the magnitude of the predicted solvation energy. The findings from this study theoretically validate the potential use of a GO/PEG nanocomposite for wound treatment application as a drug carrier for sustained release of the CEX drug.

5.
Polymers (Basel) ; 14(20)2022 Oct 20.
Article in English | MEDLINE | ID: mdl-36298009

ABSTRACT

Packaging materials are a significant part of our lives due to their daily usage at grocery stores, supermarkets, restaurants, pharmaceuticals, etc. Packaging plays an important role in ensuring that the products are preserved during handling, transporting, and storage. Similarly, it helps to maintain and prolong the shelf life of products. These materials are used for packaging meats, poultry and seafood products, food and beverages, cosmetics, and pharmaceutical products. Several applications of packaging materials have been discussed extensively, with little discussion on their end of life and continuous availability without impacting the environment. This study presents the need for sustainable packaging as a result of growing demands and the environmental impact of packaging materials after use. This study also presents the importance, types, and applications of packaging materials. Based on the findings of this study, sustainable packaging is made possible by using bio-based and recyclable materials. These materials contribute a great deal to protecting and ensuring a sustainable environment.

6.
Pharmaceutics ; 14(9)2022 Sep 19.
Article in English | MEDLINE | ID: mdl-36145719

ABSTRACT

Drug delivery systems transfer medications to target locations throughout the body. These systems are often made up of biodegradable and bioabsorbable polymers acting as delivery components. The introduction of density functional theory (DFT) has tremendously aided the application of computational material science in the design and development of drug delivery materials. The use of DFT and other computational approaches avoids time-consuming empirical processes. Therefore, this review explored how the DFT computation may be utilized to explain some of the features of polymer-based drug delivery systems. First, we went through the key aspects of DFT and provided some context. Then we looked at the essential characteristics of a polymer-based drug delivery system that DFT simulations could predict. We observed that the Gaussian software had been extensively employed by researchers, particularly with the B3LYP functional and 6-31G(d, p) basic sets for polymer-based drug delivery systems. However, to give researchers a choice of basis set for modelling complicated organic systems, such as polymer-drug complexes, we then offered possible resources and presented the future trend.

7.
Molecules ; 27(12)2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35744818

ABSTRACT

Owing to the numerous advantages of graphene-based polymer nanocomposite, this study is focused on the fabrication of the hybrid of polyvinyl alcohol (PVA), polypyrrole (PPy), and reduced graphene-oxide. The study primarily carried out the experimentation and the mathematical analysis of the electrical conductivity of PVA/PPy/rGO nanocomposite. The preparation method involves solvent/drying blending method. Scanning electron microscopy was used to observe the morphology of the nanocomposite. The electrical conductivity of the fabricated PVA/PPy/rGO nanocomposite was investigated by varying the content of PPy/rGO on PVA. From the result obtained, it was observed that at about 0.4 (wt%) of the filler content, the nanocomposite experienced continuous conduction. In addition, Ondracek, Dalmas s-shape, dose-response, and Gaussian fitting models were engaged for the analysis of the electrical transport property of the nanocomposite. The models were validated by comparing their predictions with the experimental measurements. The results obtained showed consistency with the experimental data. Moreover, this study confirmed that the electrical conductivity of polymer-composite largely depends on the weight fraction of fillers. By considering the flexibility, simplicity, and versatility of the studied models, this study suggests their deployment for the optimal characterization/simulation tools for the prediction of the electrical conductivity of polymer-composites.


Subject(s)
Graphite , Nanocomposites , Electric Conductivity , Polymers , Polyvinyl Alcohol , Pyrroles
8.
ACS Omega ; 7(51): 48447-48466, 2022 Dec 27.
Article in English | MEDLINE | ID: mdl-36619495

ABSTRACT

Conductive organic nanocomposites have been widely employed to achieve a variety of purposes, particularly for energy storage applications, making it necessary to investigate transport properties such as electron and heat transport qualities based on geometric shapes and component materials. Due to the solid B-B bonds, unique atomic structure, and energy storage potential, borophene has received significant attention due to its reported ultrahigh mechanical modulus and metallic conduction. Herein, we investigated the effect and interaction of content materials (volume fraction) and geometric parameters such as the aspect ratio and orientation of borophene nanoplatelet (BNP) inclusions on the mechanical integrity and transport features (electrical and thermal conductivities) of a poly(3,4-ethylene dioxythiophene):poly(4-styrene sulfonate) (PEDOT:PSS) electrode. The boundary condition is crucial in developing the predictive models for the optimized mechanical and transport properties of the composites. The effective modulus, electrical conductivity, and thermal conductivity of the BNP-reinforced PEDOT:PSS-based nanocomposite are evaluated using the periodic boundary condition, the representative volume element-based finite element homogenization, and statistical analysis response surface techniques. The optimal parameters for the PEDOT:PSS/BNP nanocomposite for energy storage application are predicted based on the desirability function to have a 13.96% volume fraction of BNPs, having an aspect ratio of 0.04 at 45° inclination. The desirability value achieved for the material hinges was 0.78 with a predicted Young's modulus of 6.73 GPa, the electrical conductivity was 633.85 S/cm, and the thermal conductivity was 1.96 W/m K at a generally high predictive performance of <0.03 error. The effective thermal conductivity of the nanocomposite was determined by considering Kapitsa nanoeffects, which exhibit an interfacial thermal resistance of 2.42 × 10-9 m2 K/W. Based on these improved findings, the enhanced PEDOT:PSS/BNP nanocomposite electrode would be a promising material for metal-ion batteries.

9.
Nanomaterials (Basel) ; 11(4)2021 Mar 24.
Article in English | MEDLINE | ID: mdl-33804929

ABSTRACT

In this study, the electrical properties of graphene-polypyrrole (graphene-PPy) nanocomposites were thoroughly investigated. A numerical model, based on the Simmons and McCullough equations, in conjunction with the Monte Carlo simulation approach, was developed and used to analyze the effects of the thickness of the PPy, aspect ratio diameter of graphene nanorods, and graphene intrinsic conductivity on the transport of electrons in graphene-PPy-graphene regions. The tunneling resistance is a critical factor determining the transport of electrons in composite devices. The junction capacitance of the composite was predicted. A composite with a large insulation thickness led to a poor electrochemical electrode. The dependence of the electrical conductivity of the composite on the volume fraction of the filler was studied. The results of the developed model are consistent with the percolation theory and measurement results reported in literature. The formulations presented in this study can be used for optimization, prediction, and design of polymer composite electrical properties.

10.
Polymers (Basel) ; 13(7)2021 Mar 26.
Article in English | MEDLINE | ID: mdl-33810464

ABSTRACT

In this study, a hybrid of graphene nanoplatelets with a polypyrrole having 20 wt.% loading of carbon-black (HGPPy.CB20%), has been fabricated. The thermal stability, structural changes, morphology, and the electrical conductivity of the hybrids were investigated using thermogravimetric analyzer, differential scanning calorimeter, X-ray diffraction analyzer, scanning electron microscope, and laboratory electrical conductivity device. The morphology of the hybrid shows well dispersion of graphene nanoplatelets on the surface of the PPy.CB20% and the transformation of the gravel-like PPy.CB20% shape to compact spherical shape. Moreover, the hybrid's electrical conductivity measurements showed percolation threshold at 0.15 wt.% of the graphene nanoplatelets content and the curve is non-linear. The electrical conductivity data were analyzed by comparing different existing models (Weber, Clingerman and Taherian). The results show that Taherian and Clingerman models, which consider the aspect ratio, roundness, wettability, filler electrical conductivity, surface interaction, and volume fractions, closely described the experimental data. From these results, it is evident that Taherian and Clingerman models can be modified for better prediction of the hybrids electrical conductivity measurements. In addition, this study shows that graphene nanoplatelets are essential and have a significant influence on the modification of PPy.CB20% for energy storage applications.

11.
Article in English | MEDLINE | ID: mdl-32294969

ABSTRACT

In this paper, the authors present an evaluation of the electromagnetic fields generated by a static wireless charging system designed for an electric kick scooter on the human biological tissue. The guidelines on the exposure to the electromagnetic fields are previously specified. In this work, a model is designed under COMSOL multi-physics to study the effects of the magnetic field on two possible body parts of a person, which might be exposed to this field, namely the head and the hands is analysed. The magnetic flux density, the induced electrical field, the specific absorption rate, and the resulting increase of temperature of biological tissues are modelled and compared to the limits and guidelines prescribed in the regulation established to limit the exposure of people to electromagnetic fields. Furthermore, the used wireless charging system is modified to operate at higher frequencies to study its effect. The obtained results are below the guidelines and limits of exposure to the electromagnetic fields specified by the International Commission on Non-Ionizing Radiation Protection, European Commission, Institute of Electrical and Electronics Engineers and International Electrotechnical Commission.


Subject(s)
Electricity , Electromagnetic Fields/adverse effects , Humans , Magnetic Fields , Physics
12.
Environ Sci Pollut Res Int ; 27(12): 12953-12966, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32124288

ABSTRACT

Pervasive plastic wastes, pollution and detrimental environmental ethics are a serious threat in South Africa. Compared with global trends, most studies undertaken on plastic pollutions in water bodies across South Africa have generally been limited to marine and coastal waters. A literature review, for the last 40 years, demonstrated the scanty studies on the economic, social, health and cost implications of plastic entrainment into fresh water (sources of drinking water) and wastewater systems in South Africa. Hence, demonstrating a knowledge gap on this imperative issue, the inadequate and limited frameworks needed in assessing, evaluating and re-evaluating the menace of plastic pollution and entrainments into consumable water and wastewater treatment plants. This has hampered the local capacity, manpower, knowledge and understanding direly needed for mitigating these challenges. This work is necessitated because of the dire need in bridging the knowledge gap locally by adaptively reviewing possible challenges and opportunities for South Africa in meeting up the mandate of addressing this global threat. The emerging agreement amongst global policy-makers, educators and scientists is that environmental challenges, such as this, require, now more than ever, renewed ways of effective knowledge production and decision-making in tackling, holistically the menace of mismanaged plastic wastes and pollutions. These include but not limited to plastic education curriculum, synergised policies in fostering a circular plastic economy, overriding political will, innovative waste management systems, inclusive independent monitoring of plastic wastes, robust laws and effective enforcement strategies that are needed to promote better environmental ethics, mitigation and a sustainable environment.


Subject(s)
Drinking Water , Water Pollutants, Chemical/analysis , Environmental Monitoring , Fresh Water , Plastics , South Africa , Wastewater
13.
Polymers (Basel) ; 11(8)2019 Jul 29.
Article in English | MEDLINE | ID: mdl-31362397

ABSTRACT

The problem associated with mixtures of fillers and polymers is that they result in mechanical degradation of the material (polymer) as the filler content increases. This problem will increase the weight of the material and manufacturing cost. For this reason, experimentation on the electrical conductivities of the polymer-composites (PCs) is not enough to research their electrical properties; models have to be adopted to solve the encountered challenges. Hitherto, several models by previous researchers have been developed and proposed, with each utilizing different design parameters. It is imperative to carry out analysis on these models so that the suitable one is identified. This paper indeed carried out a comprehensive parametric analysis on the existing electrical conductivity models for polymer composites. The analysis involves identification of the parameters that best predict the electrical conductivity of polymer composites for energy storage, viz: (batteries and capacitor), sensors, electronic device components, fuel cell electrodes, automotive, medical instrumentation, cathode scanners, solar cell, and military surveillance gadgets applications. The analysis showed that the existing models lack sufficient parametric ability to determine accurately the electrical conductivity of polymer-composites.

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