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Graphene oxide (GO) films can be readily prepared at wafer scale, then reduced to form graphene‐based conductive circuits relevant to a range of practical device applications. Among a variety of reduction methods, laser processing has emerged as an important technique for localized reduction and patterning of GO films. In this study, the novel use of confocal microscopy is demonstrated for high‐resolution characterization, in situ laser reduction, and versatile patterning of GO films. Multi‐modal imaging and real‐time tracking are performed with 405 and 488 nm lasers, enabling large‐area direct observation of the reduction progress. Using image analysis to cluster flake types, the different stages of reduction can be attributed to thermal transfer and accumulation. Delicate control of the reduction process over multiple length scales is illustrated using millimeter‐scale stitched patterns, micropatterning of single flakes, and direct writing conductive 2D wires with sub‐micrometer resolution (530 nm). The general applicability of the technique is shown, allowing fabrication of both conductive reduced graphene oxide (rGO) films (sheet resistance: 2.5 kOhm sq−1) and 3D microscale architectures. This simple and mask‐free method provides a valuable tool for well‐controlled and scalable fabrication of reduced GO structures using compact low‐power lasers (< 5 mW), with simultaneous in situ monitoring and quality control. [ABSTRACT FROM AUTHOR]

Keywords: confocal microscopy; graphene oxide; laser reduction; patterning EN confocal microscopy graphene oxide laser reduction patterning 1 1 1 07/27/23 20230725 NES 230725 B Confocal Microscopy b In article number 2300479, Milo S. P. Shaffer and Yuhan Li, introduce the use of confocal microscopy for multi-modal characterization, in-situ reduction, and flexible patterning of graphene oxide films. Confocal microscopy, graphene oxide, laser reduction, patterning Confocal Microscopy for In Situ Multi-Modal Characterization and Patterning of Laser-Reduced Graphene Oxide (Adv. Funct. [Extracted from the article]

The use of graphene oxide (GO) assupport has been shown previouslyto improve the CO2adsorption performance of layered doubleoxides (LDOs). In this contribution, the separate promoting effectof GO has been distinguished clearly from the influence of alkalispecies remaining from the layered double hydroxide coprecipitation.A range of sodium-free LDO and LDO/GO hybrids with relatively lowGO loadings have been prepared and characterized. These have beencompared to adsorbents with sodium residues deliberately left by minimumwashing of the precipitates. The incorporation of GO was found toenhance considerably the thermal stability of the LDO and to reducethe loss of site heterogeneity during temperature swing cycling. Theimpact of the gradual loss of surface heterogeneity of the materialson the CO2adsorption equilibrium is shown to be describedby the Toth model. CO2-TPDs did not reveal any significantmodification in the nature of the sites relevant for adsorption at573 K induced by the presence of GO in the range of loadings studied.Sodium ions incorporated by leaving residual sodium from the synthesisgreatly enhanced the adsorption capacity of the unsupported and supportedLDOs. The improved thermal stability achieved by use of GO in theLDO/GO hybrids was not affected significantly by the presence of residualsodium. Compared to other LDO supports, GO hybrids were found generallyto exhibit higher adsorption capacities per total volume of adsorbentafter multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

The alveolar respiratory unit constitutes one of the main targets of inhaled nanoparticles; the effect of engineered nanomaterials (NMs) on human health is largely unknown. Surfactant protein D (SP-D) is synthesized by alveolar type II epithelial cells and released into respiratory secretions; its main function is in immune defence, notably against inhaled microbes. SP-Dalso plays an important role in modulating an appropriate inflammatory response in the lung, and reduced SP-D is associated with a number of inflammatory lung diseases. Adsorption of SP-Dto inhaled NMs may facilitate their removal via macrophage phagocytosis. This study addresses the hypothesis that the chemistry, size and surface modification of engineered NMs will impact on their interaction with, and adsorption of, SP-D. To this purpose, we have examined the interactions between SP-D in human lung lavage and two NMs, carbon nanotubes and polystyrene nanoparticles, with different surface functionalization. We have demonstrated that particle size, functionalization and concentration affect the adsorption of SP-D from human lung lavage. Functionalization with negatively charged groups enhanced the amount of SP-D binding. While SP-D binding would be expected toenhance macrophage phagocytosis, these results suggest that the degree of binding is markedly affected by the physicochemistry of the NM and that deposition of high levels of some nanoparticles within the alveolar unit might deplete SP-D levels and affect alveolar immune defence mechanisms. [ABSTRACT FROM AUTHOR]

Well-defined ZnO nanoparticles with bound carboxylatesurface-functionalizationand narrow size distribution were prepared via an efficient organometallichydrolysis route, occurring at ambient temperature and without postsynthesisrefinement. Depending on the reaction conditions, the nanoparticles’degree of surface coverage or diameter was controlled independently.The method was used for the in situ preparation of well-dispersedZnO/epoxy resin nanocomposites. [ABSTRACT FROM AUTHOR]

The formation of porosity is a major challenge in any composite manufacturing process, particularly in the absence of vacuum assistance. Highly localized injection of polymer matrix into regions of interest in a dry preform is a route to manufacturing multi-matrix fiber-reinforced composites with high filler concentrations, which are otherwise difficult to achieve. Unlike traditional composites, such multi-matrix fiber-reinforced composite systems, which combine multiple resins in continuous form, offer improved structural performance around stress concentrators and multifunctional capabilities. As the process lacks vacuum assistance, porosity becomes a primary issue to be addressed. This paper presents a rheo-kinetic coupled rapid consolidation procedure for optimizing the quality of localized matrix patches. The procedure involves manufacturing trials and analytical consolidation models to determine the best processing program for minimal voidage in the patch. The results provide a step toward an efficient manufacturing process for the optimal design of multi-matrix composites without the need for complex vacuum bag arrangements, thus reducing cost and time while opening avenues to improve overall composite performance. [ABSTRACT FROM AUTHOR]

Nanocomposite coatings were successfully prepared by electrophoretic deposition of poly(etheretherketone) (PEEK)/graphene oxide (GO) suspensions. The GO flakes developed a large-scale co-continuous morphology with the basal plane mainly aligned with the coating surface. However, the PEEK particles were also found to be wrapped by GO nanosheets when deposited on the stainless steel substrate. Both phenomena, the co-continuous morphology and the wrapping effect, were dependent on the initial GO content in the suspension and influenced the final morphological characteristics of the thermally treated coatings. The PEEK matrix developed a dendritic morphology during its cooling from the molten state because of transcrystallinity that was induced by the incorporation of GO. The preparation of suspensions involved tip ultrasonication (TS) to deagglomerate, disperse, and mill the PEEK particles. A detailed study of the microstructure revealed that TS tended not only to reduce PEEK particle size, but also to promote an elongated shape, favourable for the nanocomposite coatings. [ABSTRACT FROM AUTHOR]

The research described in this paper primarily involves mesoscale simulations: dissipative particle dynamics (DPD) of packed assemblies of oriented fibers suspended in a viscous medium. Computer simulations have been performed in order to explore how the aspect ratio and degree of fiber alignment affect the critical volume fraction (percolation threshold) required to achieve electrical conductivity. The fiber network impedance was assessed using Monte Carlo simulations after establishing the structural arrangement with DPD. The predictions are compared with the predictions of classical percolation theory and found to be in close agreement. The approach is thus validated and can be extended to systems that cannot be tackled analytically; in particular, the work is motivated by long-standing interest in materials which display a complex percolation behavior. [ABSTRACT FROM AUTHOR]

This work applies organometallic routes to copper(0/I) nanoparticles and describes how to match ligand chemistries with different material compositions. The syntheses involve reacting an organo‐copper precursor, mesitylcopper(I) [CuMes]z (z=4, 5), at low temperatures and in organic solvents, with hydrogen, air or hydrogen sulfide to deliver Cu, Cu2O or Cu2S nanoparticles. Use of sub‐stoichiometric quantities of protonated ligand (pro‐ligand; 0.1–0.2 equivalents vs. [CuMes]z) allows saturation of surface coordination sites but avoids excess pro‐ligand contaminating the nanoparticle solutions. The pro‐ligands are nonanoic acid (HO2CR1), 2‐[2‐(2‐methoxyethoxy)ethoxy]acetic acid (HO2CR2) or di(thio)nonanoic acid, (HS2CR1), and are matched to the metallic, oxide or sulfide nanoparticles. Ligand exchange reactions reveal that copper(0) nanoparticles may be coordinated by carboxylate or di(thio)carboxylate ligands, but Cu2O is preferentially coordinated by carboxylate ligands and Cu2S by di(thio)carboxylate ligands. This work highlights the opportunities for organometallic routes to well‐defined nanoparticles and the need for appropriate ligand selection. [ABSTRACT FROM AUTHOR]

Multifunctional electrodes for structural supercapacitors are prepared by vacuum infiltration of single‐walled carbon nanotubes (SWCNTs) into woven carbon fibers (CFs); the use of reductive charging chemistry to form nanotubide solutions ensured a high degree of individualization. The route is highly versatile, as shown by comparing four different commercial nanotube feedstocks. In film form, the pure nanotubide networks ("buckypapers") are highly conductive (up to 2000 S cm−1) with high surface area (>1000 m2 g−1) and great electrochemical performance (capacitance of 101 F g−1, energy density of 27.5 Wh kg−1 and power density of 135 kW kg−1). Uniformly integrating these SWCNT networks throughout the CF fabrics significantly increased electrical conductivity (up to 318 S cm−1), surface area (up to 196 m2 g−1), and in‐plane shear properties, all simultaneously. The CNT‐infiltrated CFs electrodes exhibited intrinsically high specific energy (2.6–4.2 Wh kg−1) and power (6.0–8.7 kW kg−1) densities in pure 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM TFSI) electrolyte. Multifunctional structural supercapacitors based on CNT‐coated CFs offer a substantial increase in capacitive performance while maintaining the tensile mechanical properties of the as‐received CF‐based composite. This non‐damaging approach to modify CFs with highly graphitic, high surface area nanocarbons provides a new route to structural energy storage systems. [ABSTRACT FROM AUTHOR]

Protein crystallization remains a major bottleneck for the determination of high resolution structures. Nucleants can accelerate the process but should ideally be compatible with high throughput robotic screening. Polyethylene glycol grafted (PEGylated) graphenes can be stabilized in water providing dispensable, nucleant systems. Two graphitic feedstocks are exfoliated and functionalized with PEG using a non‐destructive, scalable, chemical reduction method, delivering good water dispersibility (80 and 750 µg mL−1 for large and small layers, respectively). The wide utility of these nucleants has been established across five proteins and three different screens, each of 96 conditions, demonstrating greater effectiveness of the dispersed PEGylated graphenes. Smaller numbers of larger, more crystalline flakes consistently act as better protein nucleants. The delivered nucleant concentration is optimized (0.1 mg mL−1 in the condition), and the performance benchmarked against existing state of the art, molecularly imprinted polymer nucleants. Strikingly, graphene nucleants are effective even when decreasing both the nucleant and protein concentration to unusually low concentrations. The set‐up to scale‐up nucleant production to liter volumes can provide sufficient material for wide implementation. Together with the optimized crystallization conditions, the results are a step forward toward practical synthesis of a readily accessible "universal" nucleant. [ABSTRACT FROM AUTHOR]

Nanomaterials, such as single‐walled carbon nanotubes (SWCNTs) and graphenes, can be readily gelled using bi‐ or multi‐functional reagents as crosslinkers. This study reports a new reaction of monofunctional acetylenes with negatively charged SWCNTs (nanotubides), prepared by reduction. Mono‐acetylenes (e. g. phenylacetylene (PAc) and diphenyl acetylene (DiPAc)) are introduced as crosslinkers to form all‐carbon SWCNT organogels at room temperature. The resulting isolated SWCNT aerogels have a density of ∼4.5–5.5 mg cm−3. Raman spectroscopy and thermogravimetric analysis suggest a covalent surface modification (∼1 functional group per 110 (PAc) and 712 (DiPAc) SWCNT carbon atoms). Significantly, the acetylene reaction does not consume all available negative charges. The SWCNT organogel is still reactive after crosslinking and can reduce a stable gold complex, chloro(triphenylphosphine)gold (I), to form AuNPs (∼12–14 nm), suggesting the formation of a living nanotubide organogel intermediate, suitable for a range of secondary reactions. Mono‐acetylenes can crosslink other negatively charged molecular systems, and surface decoration of the aerogels with other metal NPs is anticipated. [ABSTRACT FROM AUTHOR]

Electrophoretic deposition (EPD) is a powerful technique to assemble carbon nanotube (CNT) coatings and composite films with controlled architectures. This comprehensive review of the EPD of CNTs and CNT-containing composites focuses on achievements within the last 15 years and ongoing challenges. Stable CNT suspensions are a pre-requisite for successful EPD and have been prepared by a variety of strategies, discussed here. The resulting film microstructure is determined by the initial feedstock, the suspension, and the EPD approach applied, as well as a variety of EPD processing parameters. Nanocomposites can be prepared via co-deposition, sequential deposition, or post-deposition treatments, to introduce metallic, ceramic or polymeric phases. There are numerous potential applications for both homogeneous and patterned CNT films, including as structural reinforcements for composites, as field emission, energy storage and conversion devices, as well as in biomedical applications. The advantages and disadvantages of EPD processing in these contexts are discussed. [ABSTRACT FROM AUTHOR]

Intercalation of organic anions into 2D materials can enable exfoliation, improve dispersion stability, increase surface area, and provide useful functional groups. In layered metal hydroxides, intercalation of bulk structures is commonly achieved by cumbersome and typically incomplete anion exchange reactions. In contrast, here, a series of carboxylate‐intercalated layered zinc hydroxides (LZH‐R) are synthesized directly, at room temperature, by reacting an organozinc reagent with a precise sub‐stoichiometric quantity of the desired carboxylic acid and water. A range of carboxylic acids are used to make new LZH‐R materials which are crystalline, soluble, and functionalized, as established by X‐ray diffraction, spectroscopic, and microscopy techniques. When R is an alkyl ether carboxylate, this direct synthesis method results in the spontaneous exfoliation of the LZH‐R into monolayer nanosheets with high yields (70–80%) and high solubilities in alcohols and water of up to 180 mg mL−1. By altering the carboxylate ligand, functional groups suitable for post‐synthetic modification or for detection by fluorescence are also introduced. These examples demonstrate a versatile synthetic route for functional exfoliated nanosheets. [ABSTRACT FROM AUTHOR]

This paper presents a theoretical investigation into the potential use of structural power composites in regional aircraft passenger cabins and the corresponding challenges to widespread use, including fire resistance, long-term cycling performance, and cost. This study focuses on adapting sandwich floor panels with structural power composite face sheets, designed to power the in-flight entertainment system. Using a simple mechanical model to define the structural requirements, based on state-of-the-art laminated structural power composites, a series of electrochemical energy storage performance targets were calculated: a specific energy >144 (W⋅h)/kg, a specific power >0.29 kW/kg, an in-plane elastic modulus >28 GPa, and in-plane tensile and compressive strengths >219 MPa. Significantly, the use of a distributed energy storage system offered a significant range of other mass and cost savings, associated with a simplified power system, and the use of ground-generated electrical energy. For an Airbus A220-100, the analysis predicted potential mass and volume savings of approximately 260 kg and 510 l and annual reductions in CO2 and NOx emissions of approximately 280 tonnes and 1.2 tonnes respectively. This extended design analysis of a specific component highlights both the far-reaching implications of implementing structural power materials and the potential extensive systemic benefits. [ABSTRACT FROM AUTHOR]

Chemical functionalisation is one of the most active areas of graphene research, motivated by fundamental science, the opportunities to adjust or supplement intrinsic properties, and the need to assemble materials for a broad array of applications. Historically, the primary consideration has been the degree of functionalisation but there is growing interest in understanding how and where modification occurs. Reactions may proceed preferentially at edges, defects, or on graphitic faces; they may be correlated, uncorrelated, or anti-correlated with previously grafted sites. A detailed collation of existing literature data indicates that steric effects play a strong role in limiting the extent of reaction. However, the pattern of functionalisation may have important effects on the resulting properties. This article addresses the unifying principles of current graphene functionalisation technologies, with emphasis on understanding and controlling the locus of functionalisation. [ABSTRACT FROM AUTHOR]

Graphite intercalation compounds (GICs) are often used to produce exfoliated or functionalised graphene related materials (GRMs) in a specific solvent. This study explores the formation of the Na‐tetrahydrofuran (THF)‐GIC and a new ternary system based on dimethylacetamide (DMAc). Detailed comparisons of in situ temperature dependent XRD with TGA‐MS and Raman measurements reveal a series of dynamic transformations during heating. Surprisingly, the bulk of the intercalation compound is stable under ambient conditions, trapped between the graphene sheets. The heating process drives a reorganisation of the solvent and Na molecules, then an evaporation of the solvent; however, the solvent loss is arrested by restacking of the graphene layers, leading to trapped solvent bubbles. Eventually, the bubbles rupture, releasing the remaining solvent and creating expanded graphite. These trapped dopants may provide useful property enhancements, but also potentially confound measurements of grafting efficiency in liquid‐phase covalent functionalization experiments on 2D materials. [ABSTRACT FROM AUTHOR]

Abstract: Two‐dimensional (2D) layered graphitic carbon nitride (gCN) nanosheets offer intriguing electronic and chemical properties. However, the exfoliation and functionalisation of gCN for specific applications remain challenging. We report a scalable one‐pot reductive method to produce solutions of single‐ and few‐layer 2D gCN nanosheets with excellent stability in a high mass yield (35 %) from polytriazine imide. High‐resolution imaging confirmed the intact crystalline structure and identified an AB stacking for gCN layers. The charge allows deliberate organic functionalisation of dissolved gCN, providing a general route to adjust their properties. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) layered graphitic carbon nitride (gCN) nanosheets offer intriguing electronic and chemical properties. However, the exfoliation and functionalisation of gCN for specific applications remain challenging. We report a scalable one‐pot reductive method to produce solutions of single‐ and few‐layer 2D gCN nanosheets with excellent stability in a high mass yield (35 %) from polytriazine imide. High‐resolution imaging confirmed the intact crystalline structure and identified an AB stacking for gCN layers. The charge allows deliberate organic functionalisation of dissolved gCN, providing a general route to adjust their properties. [ABSTRACT FROM AUTHOR]

Abstract: The pnictogen nanomaterials, including phosphorene and arsenene, display remarkable electronic and chemical properties. Yet, the structural diversity of these main group elements is still poorly explored. Here we fill single‐wall carbon nanotubes with elemental arsenic from the vapor phase. Using electron microscopy, we find chains of highly reactive As4 molecules as well as two new one‐dimensional allotropes of arsenic: a single‐stranded zig‐zag chain and a double‐stranded zig‐zag ladder. These linear structures are important intermediates between the gas‐phase clusters of arsenic and the extended sheets of arsenene. Raman spectroscopy indicates weak electronic interaction between the arsenic and the nanotubes which implies that the formation of the new allotropes is driven primarily by the geometry of the confinement. The relative stabilities of the new arsenic structures are estimated computationally. Band‐gap calculations predict that the insulating As4 chains become semiconducting, once converted to the zig‐zag ladder, and form a fully metallic allotrope of arsenic as the zig‐zag chain. [ABSTRACT FROM AUTHOR]

Abstract: The pnictogen nanomaterials, including phosphorene and arsenene, display remarkable electronic and chemical properties. Yet, the structural diversity of these main group elements is still poorly explored. Here we fill single‐wall carbon nanotubes with elemental arsenic from the vapor phase. Using electron microscopy, we find chains of highly reactive As4 molecules as well as two new one‐dimensional allotropes of arsenic: a single‐stranded zig‐zag chain and a double‐stranded zig‐zag ladder. These linear structures are important intermediates between the gas‐phase clusters of arsenic and the extended sheets of arsenene. Raman spectroscopy indicates weak electronic interaction between the arsenic and the nanotubes which implies that the formation of the new allotropes is driven primarily by the geometry of the confinement. The relative stabilities of the new arsenic structures are estimated computationally. Band‐gap calculations predict that the insulating As4 chains become semiconducting, once converted to the zig‐zag ladder, and form a fully metallic allotrope of arsenic as the zig‐zag chain. [ABSTRACT FROM AUTHOR]

Polyester block polymers containing polylactide have garnered significant attention as renewable, degradable alternatives to traditional elastomers. However, the low glass transition of the PLA blocks limits the upper-use temperatures of the resulting elastomers. To improve the thermal performance, we explore a series of multiblock polyesters composed of poly(ε-decalactone) (PDL) and poly(cyclohexene phthalate) (PCHPE). These materials are prepared using switchable polymerization catalysis followed by chain extension. The strategy involves (i) alternating ring-opening copolymerization (ROCOP) of cyclohexene oxide and phthalic anhydride, (ii) ε-decalactone ring-opening polymerization (ROP), and (iii) diisocyanate coupling of the telechelic triblocks to increase molar mass. The resulting multiblock polyesters are amorphous, and the blocks are phase separated; glass transition temperatures are ∼−45 and 100 °C. They show thermal resistance to mass loss with Td5% ∼ 285 °C and higher upper use temperatures compared to alternative aliphatic polyesters. The nanoscale phase behavior and correlated mechanical properties are highly sensitive to the block composition. The sample containing PCHPE = 26 wt % behaves as a thermoplastic elastomer with high elongation at break (εb > 2450%), moderate tensile strength (σb = 12 MPa), and low residual strain (εr ∼ 4%). It shows elastomeric behavior from −20 to 100 °C and has a processing temperature range of ∼170 °C. At higher PCHPE content (59 wt %), the material has shape memory character with high strain fixation (250%) and recovery (96%) over multiple (25) recovery cycles. The multiblock polyesters are straightforward to prepare, and the methods presented here can be extended to produce a wide range of new materials using a other epoxides, anhydrides, and lactones. This first report on the thermal and mechanical properties highlights the significant potential for this class of polyesters as elastomers, rigid plastics, and shape memory materials. [ABSTRACT FROM AUTHOR]

A primary method for the production of 2D nanosheets is liquid-phase delamination from their 3D layered bulk analogues. Most strategies currently achieve this objective by significant mechanical energy input or chemical modification but these processes are detrimental to the structure and properties of the resulting 2D nanomaterials. Bulk poly(triazine imide) (PTI)-based carbon nitrides are layered materials with a high degree of crystalline order. Here, we demonstrate that these semiconductors are spontaneously soluble in select polar aprotic solvents, that is, without any chemical or physical intervention. In contrast to more aggressive exfoliation strategies, this thermodynamically driven dissolution process perfectly maintains the crystallographic form of the starting material, yielding solutions of defect-free, hexagonal 2D nanosheets with a well-defined size distribution. This pristine nanosheet structure results in narrow, excitation-wavelength-independent photoluminescence emission spectra. Furthermore, by controlling the aggregation state of the nanosheets, we demonstrate that the emission wavelengths can be tuned from narrow UV to broad-band white. This has potential applicability to a range of optoelectronic devices. [ABSTRACT FROM AUTHOR]

Graphene nanoplatelets (GNP) were exfoliated using a nondestructive chemical reduction method and subsequently decorated with polymers using two different approaches: grafting from and grafting to. Poly(methyl methacrylate) (PMMA) with varying molecular weights was covalently attached to the GNP layers using both methods. The grafting ratios were higher (44.6% to 126.5%) for the grafting from approach compared to the grafting to approach (12.6% to 20.3%). The products were characterized using thermogravimetric analysis-mass spectrometry (TGA-MS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The grafting from products showed an increase in the grafting ratio and dispersibility in acetone with increasing monomer supply; on the other hand, due to steric effects, the grafting to products showed lower absolute grafting ratios and a decreasing trend with increasing polymer molecular weight. The excellent dispersibility of the grafting from functionalized graphene, 900 μg/mL in acetone, indicates an increased compatibility with the solvent and the potential to increase graphene reinforcement performance in nanocomposite applications. [ABSTRACT FROM AUTHOR]

Elemental phosphorus displays an impressive number of allotropes with highly diverse chemical and physical properties. White phosphorus has now been filled into single-wall carbon nanotubes (SWCNTs) from the liquid and thereby stabilized against the highly exothermic reaction with atmospheric oxygen. The encapsulated tetraphosphorus molecules were visualized with transmission electron microscopy, but found to convert readily into chain structures inside the SWCNT 'nanoreactors'. The energies of the possible chain structures were determined computationally, highlighting a delicate balance between the extent of polymerization and the SWCNT diameter. Experimentally, a single-stranded zig-zag chain of phosphorus atoms was observed, which is the lowest energy structure at small confinement diameters. These one-dimensional chains provide a glimpse into the very first steps of the transformation from white to red phosphorus. [ABSTRACT FROM AUTHOR]

Elemental phosphorus displays an impressive number of allotropes with highly diverse chemical and physical properties. White phosphorus has now been filled into single-wall carbon nanotubes (SWCNTs) from the liquid and thereby stabilized against the highly exothermic reaction with atmospheric oxygen. The encapsulated tetraphosphorus molecules were visualized with transmission electron microscopy, but found to convert readily into chain structures inside the SWCNT 'nanoreactors'. The energies of the possible chain structures were determined computationally, highlighting a delicate balance between the extent of polymerization and the SWCNT diameter. Experimentally, a single-stranded zig-zag chain of phosphorus atoms was observed, which is the lowest energy structure at small confinement diameters. These one-dimensional chains provide a glimpse into the very first steps of the transformation from white to red phosphorus. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) can be evenly deposited on single-walled carbon nanotubes (SWCNTs) via the reduction of the highly stable complex, chloro(triphenylphosphine) gold(i), with SWCNT anions (‘nanotubides’). This methodology highlights the unusual chemistry of nanotubides and provides a blueprint for the generation of many other hybrid nanomaterials. [ABSTRACT FROM AUTHOR]

Sonicating pure N-methyl pyrrolidone (NMP) rapidly produces contaminating organic nanoparticles, at increasing concentration with time, as investigated by AFM, as well as UV-vis, IR and NMR spectroscopies. The contamination issue affects carbon nanotube, and likely other nanomaterial, dispersions processed by sonication in organic solvents. [ABSTRACT FROM AUTHOR]

The increase of production volumes of silver nanowires (AgNWs) and of consumer products incorporating them may lead to increased health risks from occupational and public exposures. There is currently limited information about the putative toxicity of AgNWs upon inhalation and incomplete understanding of the properties that control their bioreactivity. The lung lining fluid (LLF), which contains phospholipids and surfactant proteins, represents a first contact site with the respiratory system. In this work, the impact of dipalmitoylphosphatidylcholine (DPPC), Curosurf, and murine LLF on the stability of AgNWs was examined. Both the phospholipid and protein components of the LLF modified the dissolution kinetics of AgNWs, due to the formation of a lipid corona or aggregation of the AgNWs. Moreover, the hydrophilic proteins, but neither the hydrophobic surfactant proteins nor the phospholipids, induced agglomeration of the AgNWs. Finally, the generation of a secondary population of nanosilver was observed and attributed to the reduction of Ag+ ions by the surface capping of the AgNWs. Our findings highlight that combinations of spatially resolved dynamic and static techniques are required to develop a holistic understanding of which parameters govern AgNW behavior at the point of exposure and to accurately predict their risks on human health and the environment. [ABSTRACT FROM AUTHOR]

The prevalence of healthcare-associated infection caused by multidrug-resistant bacteria is of critical concern worldwide. It is reported on the development of a bactericidal surface prepared by use of a simple, upscalable, two-step dipping strategy to incorporate crystal violet and di(octyl)­phosphinic- acid-capped zinc oxide nanoparticles into medical grade silicone, as a strategy to reduce the risk of infection. The material is characterized by UV-vis absorbance spectroscopy, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma-optical emission spectroscopy (ICP-OES) and transmission electron microscopy (TEM) and confirmed the incorporation of the ZnO nanoparticles in the polymer. The novel system proves to be a highly versatile bactericidal material when tested against both Staphylococcus aureus and Escherichia coli, key causative micro-organisms for hospital-acquired infection (HAI). Potent antimicrobial activity is noted under dark conditions, with a significant enhancement exhibits when the surfaces are illuminated with a standard hospital light source. This polymer has the potential to decrease the risk of HAI, by killing bacteria in contact with the surface. [ABSTRACT FROM AUTHOR]

The Joule heating properties of an ultralight nanocarbon aerogel are investigated with a view to potential applications as energy-efficient, local gas heater, and other systems. Thermally reduced graphene oxide (rGO) aerogels (10 mg cm−3) with defined shape are produced via emulsion-templating. Relevant material properties, including thermal conductivity, electrical conductivity and porosity, are assessed. Repeatable Joule heating up to 200 °C at comparatively low voltages (≈1 V) and electrical power inputs (≈2.5 W cm−3) is demonstrated. The steady-state core and surface temperatures are measured, analyzed and compared to analogous two-dimensional nanocarbon film heaters. The assessment of temperature uniformity suggests that heat losses are dominated by conductive and convective heat dissipation at the temperature range studied. The radial temperature gradient of an uninsulated, Joule-heated sample is analyzed to estimate the aerogel's thermal conductivity (around 0.4 W m−1 K−1). Fast initial Joule heating kinetics and cooling rates (up to 10 K s−1) are exploited for rapid and repeatable temperature cycling, important for potential applications as local gas heaters, in catalysis, and for regenerable of solid adsorbents. These principles may be relevant to wide range of nanocarbon networks and applications. [ABSTRACT FROM AUTHOR]

Fullerene[60] (C60) and poly(ethylene glycol) (PEG)adducts were prepared via 1,3-dipolar cycloaddition of bis-azido-terminatedlinear PEG (N3-PEG-N3) and C60. Whilelong chain length PEGs (Mn= 1000 and3350 Da) yielded the cyclic diamond ring structures (⊂C60PEG1000⊃and ⊂C60PEG3350⊃), short-chained PEG (Mn= 200 Da) yielded a telechelic dumbbell structure (C60-PEG200-C60). Both dumbbell and diamondring structures were characterized by MALDI-TOF-MS, 1HNMR, FTIR, UV–vis, and elemental analysis (EA). The resultshighlight the structural dependence of the PEG-C60adductson the chain length of the azido-terminated polymer, a factor previouslyneglected. [ABSTRACT FROM AUTHOR]

The synthesis, characterization,and zinc coordination chemistryof the three proligands 2-tert-butyl-4-[tert-butyl (1)/methoxy (2)/nitro (3)]-6-{[(2′-dimethylaminoethyl)methylamino]methyl}phenol aredescribed. Each of the ligands was reacted with diethylzinc to yieldzinc ethyl complexes 4–6; these complexeswere subsequently reacted with phenylsilanol to yield zinc siloxidecomplexes 7–9. Finally, the zincsiloxide complexes were reacted with phenylsilane to produce the threenew zinc hydride complexes 10–12.The new complexes 4–12have beenfully characterized by NMR spectroscopy, mass spectrometry, and elementalanalyses. The structures of the zinc hydride complexes have been probedusing VT-NMR spectroscopy and X-ray diffraction experiments. Thesedata indicate that the complexes exhibit mononuclear structures at298 K, both in the solid state and in solution (d8-toluene). At 203 K, the NMR signals broaden, consistentwith an equilibrium between the mononuclear and dinuclear bis(μ-hydrido)complexes. All three zinc hydride complexes react rapidly and quantitativelywith carbon dioxide, at 298 K and 1 bar of pressure over 20 min, toform the new zinc formate complexes 13–15. The zinc formate complexes have been analyzed by NMR spectroscopyand VT-NMR studies, which reveal a temperature-dependent monomer–dimerequilibrium that is dominated by the mononuclear species at 298 K. [ABSTRACT FROM AUTHOR]

Two-dimensional TiO2anatasenanoplatelets can be synthesizedvia solvothermal reaction of titanium(IV) isopropoxide in the presenceof structure-directing hydrogen fluoride. High resolution electrontransmission microscopy (HRTEM), selected area electron diffraction(SAED), and X-ray powder diffraction (XRD) show that the resultingnanoplatelets are heavily–truncated, octahedral TiO2anatase nanocrystals with a large fraction of high-energy (001)crystal facets. Systematic studies provide insight into the underlyingreaction pathways and the competing, morphology-determining rolesof hydrogen fluoride and water during nanocrystal formation. TiF4can be used as an additional or alternative fluoride sourcein hydrolytic systems, allowing the study of markedly higher fluorideconcentrations than previously reported, and/or avoiding the use ofHF as a starting material. The findings can be plotted on a HF:H2O:Ti ternary diagram to provide guidelines for the controlof average dimensions, aspect ratio, degree of truncation and, thereby,fraction of (001) crystal facets. Depending on the composition ofthe reaction system, oriented attachment of the anatase nanoplateletsalong either (001) or (101) facets can be observed. The photocatalyticactivity of nananocrystals with different aspect ratios, determinedin dye degradation experiments, demonstrates higher activity of the(001) than (101) anatase facets. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) show great potentialas CO2adsorbent materials, but require improvements instabilityand CO2adsorption capacity for commercial applications.In the current study, graphene oxide provides a light-weight, charge-complementary,two-dimensional (2D) material that interacts effectively with the2D LDHs, in turn enhancing the CO2uptake capacity andmulticycle stability of the assembly. As a result, the absolute capacityof the LDH was increased by 62% using only 7 wt % grapheneoxide (GO) as a support. The experimental procedure for the synthesisof the materials is based on a direct precipitation of the LDH nanoparticlesonto GO followed by a structural and physical characterization byelectron microscopy, X-ray diffraction, thermogravimetric analysis,and Brunauer–Emmett–Teller (BET) surface area measurements.Detailed titration confirmed the compatibility of the surface chemistry.After thermal decomposition, mixed metal oxides (MMOs) are obtainedwith the basic sites required for the CO2adsorption. Arange of samples with different proportions of GO/MMO were prepared,fully characterized, and correlated with the CO2sorptioncapacity, established via TGA. [ABSTRACT FROM AUTHOR]

Solutions of negatively charged graphene (graphenide) platelets were produced by intercalation of nanographite with liquid potassium-ammonia followed by dissolution in tetrahydrofuran. The structure and morphology of these solutions were then investigated by small-angle neutron scattering. We found that >95 vol % of the solute is present as single-layer graphene sheets. These charged sheets are flat over a length scale of >150 Å in solution and are strongly solvated by a shell of solvent molecules. Atomic force microscopy on drop-coated thin films corroborated the presence of monolayer graphene sheets. Our dissolution method thus offers a significant increase in the monodispersity achievable in graphene solutions. [ABSTRACT FROM AUTHOR]

The development of a model CNT-brittle matrix composite system, based on SiO glass containing well-dispersed CNTs at up to 15 wt%, allows a direct assessment of the effect of the nanoscale filler on fracture toughness ( K). Samples were prepared by colloidal heterocoagulation followed by spark plasma sintering. Detailed K measurements, using both indentation and notched beam techniques, show a linear improvement with CNT content, with up to a twofold increase of fracture toughness at maximum loading. The results from the two methods used in this study show equivalent trends but differing absolute values; the relative merits of these two approaches to measuring nanocomposite toughness are compared. Possible toughening mechanisms associated with CNT pull-out, crack bridging, and crack deflection are identified, and discussed quantitatively, drawing on conventional short-fibre composite theory and the potential effects of scaling fibre diameter. [ABSTRACT FROM AUTHOR]

Polymer electrolyte fuel cells hold great promise for a range of applications but require advances in durability for widespread commercial uptake. Corrosion of the carbon support is one of the main degradation pathways; hence, corrosion-resilient graphene has been widely suggested as an alternative to traditional carbon black. However, the performance of bulk graphene-based electrodes is typically lower than that of commercial carbon black due to their stacking effects. This article reports a simple, scalable and non-destructive method through which the pore structure and platinum utilisation of graphene-based membrane electrode assemblies can be significantly improved. Urea is incorporated into the catalyst ink before deposition, and is then simply removed from the catalyst layer after spraying by submerging the electrode in water. This additive hinders graphene restacking and increases porosity, resulting in a significant increase in Pt utilisation and current density. This technique does not require harsh template etching and it represents a pathway to significantly improve graphene-based electrodes by introducing hierarchical porosity using scalable liquid processes. [ABSTRACT FROM AUTHOR]

The development of commercial aviation is being driven by the need to improve efficiency and thereby lower emissions. All-electric aircraft present a route to eliminating direct fuel burning emissions, but their development is stifled by the limitations of current battery energy and power densities. Multifunctional structural power composites, which combine load-bearing and energy-storing functions, offer an alternative to higher-energy-density batteries and will potentially enable lighter and safer electric aircraft. This study investigated the feasibility of integrating structural power composites into future electric aircraft and assessed the impact on emissions. Using the Airbus A320 as a platform, three different electric aircraft configurations were designed conceptually, incorporating structural power composites, slender wings and distributed propulsion. The specific energy and power required for the structural power composites were estimated by determining the aircraft mission performance requirements and weight. Compared to a conventional A320, a parallel hybrid-electric A320 with structural power composites >200 Wh/kg could potentially increase fuel efficiency by 15% for a 1500 km mission. For an all-electric A320, structural power composites >400 Wh/kg could halve the specific energy or mass of batteries needed to power a 1000 km flight. [ABSTRACT FROM AUTHOR]

This paper reviews the scientific literature concerning urushi lacquers. Urushi has been used by skilled lacquer artists for thousands of years, predominantly in the East Asian countries of Japan, Korea and China, where there is an abundance of urushi-producing trees. Spectacular lacquered artefacts still exist due to the stability of the material, and numerous conservation efforts endeavour to preserve these pieces. This review discusses the chemical properties of this complex material, with particular reference to its stability and durability, and the conditions that contribute to its deterioration. The importance of understanding these properties is discussed with regard to the conservation of urushi-based objects. [ABSTRACT FROM AUTHOR]

2D nanosheets, exfoliation, intercalation, layered zinc hydroxides, organozinc Layered Zinc Hydroxides: Direct Organometallic Synthesis of Carboxylate Intercalated Layered Zinc Hydroxides for Fully Exfoliated Functional Nanosheets (Adv. Funct. Keywords: 2D nanosheets; exfoliation; intercalation; layered zinc hydroxides; organozinc EN 2D nanosheets exfoliation intercalation layered zinc hydroxides organozinc 1 1 1 07/27/21 20210723 NES 210723 In article number 2102631, Milo S. P. Shaffer, Charlotte K. Williams, and co-workers present a direct and versatile organometallic route to carboxylate-intercalated layered zinc hydroxide (LZH) 2D nanosheets. [Extracted from the article]

This communication presents a clean and efficient in situ method for the preparation of thermoset composites containing ZnO nanoparticles and/or ZnO-coated carbon nanotubes. [ABSTRACT FROM AUTHOR]

This communication presents a clean and efficient in situmethod for the preparation of thermoset composites containing ZnO nanoparticles and/or ZnO-coated carbon nanotubes. [ABSTRACT FROM AUTHOR]

Keywords: 2D materials; exfoliation; graphene; graphite intercalation compounds; X-ray diffraction EN 2D materials exfoliation graphene graphite intercalation compounds X-ray diffraction 6291 6291 1 05/23/20 20200520 NES 200520 B Graphite Intercalation compounds (GICs) b are often used to produce exfoliated or functionalized graphene related materials in a specific solvent. 2D materials, exfoliation, graphene, graphite intercalation compounds, X-ray diffraction. [Extracted from the article]

Silver nanoparticles (AgNP) are known to penetrate into the brain and cause neuronal death. However, there is a paucity in studies examining the effect of AgNP on the resident immune cells of the brain, microglia. Given microglia are implicated in neurodegenerative disorders such as Parkinson's disease (PD), it is important to examine how AgNPs affect microglial inflammation to fully assess AgNP neurotoxicity. In addition, understanding AgNP processing by microglia will allow better prediction of their long term bioreactivity. In the present study, the in vitro uptake and intracellular transformation of citrate-capped AgNPs by microglia, as well as their effects on microglial inflammation and related neurotoxicity were examined. Analytical microscopy demonstrated internalization and dissolution of AgNPs within microglia and formation of non-reactive silver sulphide (Ag2S) on the surface of AgNPs. Furthermore, AgNP-treatment up-regulated microglial expression of the hydrogen sulphide (H2S)-synthesizing enzyme cystathionine-γ-lyase (CSE). In addition, AgNPs showed significant anti-inflammatory effects, reducing lipopolysaccharide (LPS)-stimulated ROS, nitric oxide and TNFα production, which translated into reduced microglial toxicity towards dopaminergic neurons. Hence, the present results indicate that intracellular Ag2S formation, resulting from CSE-mediated H2S production in microglia, sequesters Ag+ ions released from AgNPs, significantly limiting their toxicity, concomitantly reducing microglial inflammation and related neurotoxicity. [ABSTRACT FROM AUTHOR]

On page 1367 I. P. Parkin and co‐workers showcase the development of a potent and versatile antimicrobial material. Silicone polymer with incorporated zinc oxide nanoparticles (nano‐ZnO) and crystal violet dye demonstrates strong antimicrobial activity against key causative bacteria for hospital‐acquired infections. The nano‐ZnO at the polymer surface, in combination with radicals generated upon whitelight illumination of the dye, kill both Gram‐positive and Gramnegative bacteria through multiple attack mechanisms. [ABSTRACT FROM AUTHOR]

On page 28, a fundamental study of the direct resistive heating of emulsion‐templated graphene aerogels demonstrates reliable, fast, energy‐efficient and uniform temperature control of the graphene framework. R. Menzel, M. S. P. Shaffer, and team's findings lay a framework that may be exploited in a wide range of novel applications for nanocarbon aerogels, including flow‐through local gas heaters, temperature‐sensitive catalytic reactions, and thermally regenerable filter and storage systems. [ABSTRACT FROM AUTHOR]