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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]

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]

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]

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]

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]

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]