The interfacial compatibility issue of boron nitride (BN) nanofillers in epoxy resin (EP) matrix is one of the major challenges plaguing the efficient application of composites. Herein, inspired by ...phenol-amine green chemistry, microwave-assisted ball milling was used to synthesize tannic acid (TA) and polyethyleneimine (PEI) functionalized boron nitride (TA/PEI@BN). Characterization indicated that TA/PEI grafted on BN via both non-covalent and covalent interactions, which improved the interfacial compatibility and cross-linking properties of TA/PEI@BN within the EP. Meanwhile, the introduction of 0.25 % TA/PEI@BN reduced the average friction coefficient and wear rate of the EP composite coating by 17 % and 50 %, respectively. The characterization of the friction interface showed that TA/PEI@BN could exhibit a "sliding complementary repair" effect during friction. This work presents a novel, green, and scalable method for realizing the surface functionalization of BN, beneficial for the further application of high-performance epoxy matrix composites.
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•TA/PEI functionalized BN (TA/PEI@BN) was synthesized by microwave-assisted ball milling.•Microwave-assisted ball milling had a facilitating effect on the cross-linking reaction of TA and PEI.•TA/PEI@BN has good interfacial compatibility in epoxy resins.•TA/PEI@BN/EP composite coatings have improved tribological properties.•The frictional wear process of epoxy composite coatings was modeled.
Polymeric Nanoparticles
In article number 2310876, Behnam Akhavan and co‐workers discuss recent breakthroughs in surface bioengineering of polymeric nanoparticles. They emphasize the significance of ...distinguishing between covalent and noncovalent bonding mechanisms for the effective attachment of bioactive moieties to nanoparticle surfaces. Surface bioengineering of polymeric nanoparticles unlocks groundbreaking opportunities in diagnostics, therapies, and beyond.
Laser engineering of biomimetic surfaces Stratakis, E.; Bonse, J.; Heitz, J. ...
Materials science & engineering. R, Reports : a review journal,
July 2020, 2020-07-00, Letnik:
141
Journal Article
Recenzirano
Odprti dostop
The exciting properties of micro- and nano-patterned surfaces found in natural species hide a virtually endless potential of technological ideas, opening new opportunities for innovation and ...exploitation in materials science and engineering. Due to the diversity of biomimetic surface functionalities, inspirations from natural surfaces are interesting for a broad range of applications in engineering, including phenomena of adhesion, friction, wear, lubrication, wetting phenomena, self-cleaning, antifouling, antibacterial phenomena, thermoregulation and optics. Lasers are increasingly proving to be promising tools for the precise and controlled structuring of materials at micro- and nano-scales. When ultrashort-pulsed lasers are used, the optimal interplay between laser and material parameters enables structuring down to the nanometer scale. Besides this, a unique aspect of laser processing technology is the possibility for material modifications at multiple (hierarchical) length scales, leading to the complex biomimetic micro- and nano-scale patterns, while adding a new dimension to structure optimization. This article reviews the current state of the art of laser processing methodologies, which are being used for the fabrication of bioinspired artificial surfaces to realize extraordinary wetting, optical, mechanical, and biological-active properties for numerous applications. The innovative aspect of laser functionalized biomimetic surfaces for a wide variety of current and future applications is particularly demonstrated and discussed. The article concludes with illustrating the wealth of arising possibilities and the number of new laser micro/nano fabrication approaches for obtaining complex high-resolution features, which prescribe a future where control of structures and subsequent functionalities are beyond our current imagination.
Owing to its intrinsic structure, thermal stability and dimension effects, black phosphorene (BP) has great potential in manufacturing advanced-performance polymer composites. However, the ...shortcoming of instability and re-agglomeration enables great challenges toward its application. Herein, a lanthanide metal ligand ((CF3SO3)3Er) has been employed to decorate few-layer BP nanosheets. By means of density functional theory (DFT), there is a high adsorption energy of −1.49 eV in the system, which confirms a powerful adsorbing effect is existed between BP and (CF3SO3)3Er. Due to the charge transfer from BP to (CF3SO3)3Er molecule, the lone-pair electrons of BP are passivated, thereby the decorated BP (Er-BP) exhibits robust stability in ambient conditions and common solvents. Whereafter, the Er-BP is loading into epoxy resin (EP) to manufacture EP-based composites. The Er-BP can not only effectively enhance the dispersion of BP in EP substrate, but also catalyze the curing process of EP nanocomposites. When the amount of Er-BP in epoxy is 3.0 wt%, the residual char content is clearly improved by 75.42%, which is attributed to the coadjutant catalytic charring function between BP and (CF3SO3)3Er. EP/Er-BP 3.0 sample can meet the requirement of UL-94 V-0 testing, and the limiting oxygen index (LOI) value is improved from 24.7% to 30.3%. Meanwhile, there is a 61.37% reduction in the peak heat release rate (PHRR) and a 36.68% decrease in the total heat release (THR). The smoke production rate (SPR) and total smoke production (TSP) are also decreased by 62.90% and 55.94%, respectively. Particularly, the amount of CO released per second (COP) is dramatically reduced by 74.24%, implying that the heat and smoke release has been significantly suppressed due to the production of protective char layer.
This paper reviews recent developments in the preparation, surface functionalization, and applications of Fe3O4 magnetic nanoparticles. Especially, it includes preparation methods (such as ...electrodeposition, polyol methods, etc.), organic materials (such as polymers, small molecules, surfactants, biomolecules, etc.) or inorganic materials (such as silica, metals, and metal oxidation/sulfide, functionalized coating of carbon surface, graphene, etc.) and its applications (such as magnetic separation, protein fixation, magnetic catalyst, environmental treatment, medical research, etc.). In the end, some existing challenges and possible future trends in the field were discussed.
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•Comprehensive summary of the main aspects of Fe3O4 magnetic nanoparticles related to their preparation and application.•Classification and intrinsic properties of Fe3O4 magnetic nanoparticles were studied.•Perspectives for the future developments of Fe3O4 magnetic nanoparticles were proposed.
The efficient degradation and accurate quantification of tetracycline in environment and food samples is pivotal for ensuring public health and safety by monitoring potential contamination and ...maintaining regulatory standards. Hence, in this study, photocatalytic degradation of tetracycline and its electrochemical detection in environment and food samples based on dual-functional silver-doped zinc ferrite nanoparticles embedded chitosan-functionalized carbon nanofibers fabricated on a screen-printed carbon electrode (AgZFO/CHIT-CNF/SPCE) is presented. A hydrothermal method was used in the synthesis of Ag-doped ZFO, and chitosan was functionalized on the CNF surface using a swift and cost-effective chemical modification process of carboxyl groups. Various techniques, such as XRD, HRTEM, elemental mapping, EIS, XPS, FTIR, VSM, BET, UV–Vis DRS, and Raman spectroscopy were used to analyze the characteristics of the prepared nanocomposite. Cyclic voltammetry and differential pulse voltammetry were used to evaluate the surface-controlled electrocatalytic properties of AgZFO/CHIT-CNF towards tetracycline. Electrochemical tests revealed that the proposed electrode exhibited excellent sensitivity for detecting tetracycline. The fabricated electrode had a low detection limit of 1 nM and a wide linear range (0.2–53.2 μM). The sensor also demonstrated exceptional selectivity, stability, and reusability. The practical feasibility evaluated with real samples, including chicken feed, shrimp, milk, soil, and wastewater, resulted in high recovery values.
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•Ultrasensitive detection of polyketide drug tetracycline based on AgZFO/CHIT-CNF/SPCE.•Photocatalytic degradation of tetracycline with high efficiency (95.72%) using dual-functional nanocomposite.•This is the first work that reports tetracycline detection using ZFO based nanomaterial.•A very low detection limit (1 nM) in nanomolar range was achieved for proposed sensor.•High recovery values for practical feasibility analysis in wastewater, soil, chicken feed, shrimp, and milk.
<img src=” https://s3.amazonaws.com/production.scholastica/article/35650/large/photo-1597423498323-e7e7554b83c6?1652369616”> Biomedical applications in medicine are an area of research studied in ...great breadth, covering the various potential applications. Mimicking natural processes promises to be a successful strategy for several reasons. For example, physiological structures can generate drug delivery platforms that are better tolerated by the immune system. Furthermore, physiological movement patterns in flagella or contracting motions, which originate from unicellular organisms, are imi-tated. Further examples are stimuli-responsive tissue structures that serve the regeneration of bone material by stimulating pre-osteoblasts to proliferate. The examples of bioinspired SPIONs discussed in this review span the fields of drug delivery, imaging/diagnostics, nano/micromotion, and tissue engineering. All these concepts need to be evaluated regarding their technical feasibility and translatability into the clinic. Therefore, this text concludes with a general consideration for clinically proving such developments.
We report here an investigation of the role that various carbon supports have on a model non-precious metal catalyst for the oxygen reduction reaction (ORR) prepared through a molecularly defined ...terpyridine moiety covalently embedded onto various high surface area carbons (Black Pearls 2000, Ketjen Black 600, Multi-Walled Carbon Nanotubes). A terpyridine modified catalyst has been previously prepared and allowed for the controlled deposition of one specific and unique N3/C active site on the surface of the support. The effect of changing the porosity and surface area of the carbon was analyzed for its oxygen reduction reaction activity and characterized using thermogravimetric analysis, pore size determination, and rotating disk measurements. This system showed that when a more microporous support was used the activity for the oxygen reduction reaction was significantly decreased in acidic media, this could be explained by the differences in the formation and overall accessibility of the active sites on the high surface area supports.
The search for effective materials for environmental cleanup is a scientific and technological issue of paramount importance. Among various materials, carbon nanotubes (CNTs) possess unique ...physicochemical, electrical, and mechanical properties that make them suitable for potential applications as environmental adsorbents, sensors, membranes, and catalysts. Depending on the intended application and the chemical nature of the target contaminants, CNTs can be designed through specific functionalization or modification processes. Designer CNTs can remarkably enhance contaminant removal efficiency and facilitate nanomaterial recovery and regeneration. An increasing number of CNT-based materials have been used to treat diverse organic, inorganic, and biological contaminants. These success stories demonstrate their strong potential in practical applications, including wastewater purification and desalination. However, CNT-based technologies have not been broadly accepted for commercial use due to their prohibitive cost and the complex interactions of CNTs with other abiotic and biotic environmental components. This paper presents a critical review of the existing literature on the interaction of various contaminants with CNTs in water and soil environments. The preparation methods of various designer CNTs (surface functionalized and/or modified) and the functional relationships between their physicochemical characteristics and environmental uses are discussed. This review will also help to identify the research gaps that must be addressed for enhancing the commercial acceptance of CNTs in the environmental remediation industry.
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•CNTs can be designed through specific functionalization or modification process.•Designer CNTs can enhance contaminant removal efficiency.•CNTs can facilitate recovery and regeneration of nanomaterials.•CNTs hold potential applications in wastewater purification and desalination.•Further research is needed to enhance commercial acceptance of CNTs.
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•Preparing MXene-PZN hybrid via polymerization of phosphazene on MXene surface.•The dispersion and interface interaction of MXene-PZN within EP matrix is improved.•EP/MXene-PZN ...composites achieve better mechanical properties and flame retardancy.•MXene catalyzes PZN charring to form a char layer on MXene surface as burning.•Reserved 2D structure of MXene leads to superior flame retardancy of EP/MXene-PZN.
As a promising flame retardant, Titanium carbide (Ti3C2TX) MXene has shown synergetic flame retardancy with various modifying agents, especially phosphorus/nitrogen-containing flame retardants. However, the synergetic flame-retardancy mechanism of Ti3C2TX and modifying agent are unclear due to the complexity of reactions during the combustion process. Herein, polyphosphazene-functionalized Ti3C2TX nanosheets (MXene-PZN) were prepared and then added to epoxy resin (EP) to prepare the EP/MXene-PZN composites. Subsequently, the mechanical properties and the flame-retardant performance and mechanism were systematically investigated. The results showed an improved interfacial interaction and excellent compatibility of MXene-PZN nanosheets in the EP matrix, resulting in the storage modulus and tensile strength of EP/MXene-PZN-2.0 being increased by 46.5% and 68.4% respectively, as 2 wt% MXene-PZN was added into the EP matrix. Moreover, the flame-retardant tests showed that the peak heat release rate and total heat release of EP/MXene-PZN-2.0 were reduced by 44.8% and 54.8%, respectively, compared with pure EP, while 49.4% and 41.9% decrease in the peak CO production rate and the peak CO2 production rate were also achieved. Finally, focusing on the main existing forms of MXene-PZN in the EP matrix during different combustion stages, the flame-retardant mechanism of MXene-PZN functioned both in the condensed phase and gaseous phase was established. Thus, this work demonstrates a facile yet promising strategy to design efficient synergetic flame retardants.
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