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Pseudomonas aeruginosa(P. aeruginosa) is an opportunistic pathogen causing infections in blood and implanted devices. Traditional identification methods take more than 24 h to produce results. Molecular biology methods expedite detection, but require an advanced skill set. To address these challenges, this work demonstrates functionalization of laser‐induced graphene (LIG) for developing flexible electrochemical sensors forP. aeruginosabased on phenazines. Electrodeposition as a facile approach is used to functionalize LIG with molybdenum polysulfide (MoS_x). The sensor's limit of detection (LOD), sensitivity, and specificity are determined in broth, agar, and wound simulating medium (WSM). Control experiments withEscherichia coli, which does not produce phenazines, demonstrate specificity of sensors forP. aeruginosa. The LOD for pyocyanin (PYO) and phenazine‐1‐carboxylic acid (PCA) is 0.19 × 10⁻⁶ and 1.2 × 10⁻⁶ m, respectively. Furthermore, the highly stable sensors enable real‐time monitoring ofP. aeruginosabiofilms over several days. Comparing square wave voltammetry data over time shows time‐dependent generation of phenazines. In particular, two configurations—“Normal” and “Flipped”—are studied, showing that the phenazines time dynamics vary depending on how cells interact with sensors. The reported results demonstrate the potential of the developed sensors for integration with wound dressings for early diagnosis ofP. aeruginosainfection.

 

Thermoelectric generators (TEGs) convert temperature differences into electrical power and are attractive among energy harvesting devices due to their autonomous and silent operation. While thermoelectric materials have undergone substantial improvements in material properties, a reliable and cost-effective fabrication method suitable for microgravity and space applications remains a challenge, particularly as commercial space flight and extended crewed space missions increase in frequency. This paper demonstrates the use of plasma-jet printing (PJP), a gravity-independent, electromagnetic field-assisted printing technology, to deposit colloidal thermoelectric nanoflakes with engineered nanopores onto flexible substrates at room temperature. We observe substantial improvements in material adhesion and flexibility with less than 2% and 11% variation in performance after 10 000 bending cycles over 25 mm and 8 mm radii of curvature, respectively, as compared to previously reported TE films. Our printed films demonstrate electrical conductivity of 2.5 × 10 3 S m −1 and a power factor of 70 μW m −1 K −2 at room temperature. To our knowledge, these are the first reported values of plasma-jet printed thermoelectric nanomaterial films. This advancement in plasma jet printing significantly promotes the development of nanoengineered 2D and layered materials not only for energy harvesting but also for the development of large-scale flexible electronics and sensors for both space and commercial applications. 

Abstract Formation of mineral scale on a material surface has profound impact on a wide range of natural processes as well as industrial applications. However, how specific material surface characteristics affect the mineral-surface interactions and subsequent mineral scale formation is not well understood. Here we report the superior resistance of hexagonal boron nitride ( h BN) to mineral scale formation compared to not only common metal and polymer surfaces but also the highly scaling-resistant graphene, making h BN possibly the most scaling resistant material reported to date. Experimental and simulation results reveal that this ultrahigh scaling-resistance is attributed to the combination of h BN’s atomically-smooth surface, in-plane atomic energy corrugation due to the polar boron-nitrogen bond, and the close match between its interatomic spacing and the size of water molecules. The latter two properties lead to strong polar interactions with water and hence the formation of a dense hydration layer, which strongly hinders the approach of mineral ions and crystals, decreasing both surface heterogeneous nucleation and crystal attachment. 

To enable greater control over thermal atomic layer deposition (ALD) of molybdenum disulfide (MoS 2 ), here we report studies of the reactions of molybdenum hexafluoride (MoF 6 ) and hydrogen sulfide (H 2 S) with metal oxide substrates from nucleation to few-layer films. In situ quartz crystal microbalance experiments performed at 150, 200, and 250 °C revealed temperature-dependent nucleation behavior of the MoF 6 precursor, which is attributed to variations in surface hydroxyl concentration with temperature. In situ Fourier transform infrared spectroscopy coupled with ex situ x-ray photoelectron spectroscopy (XPS) indicated the presence of molybdenum oxide and molybdenum oxyfluoride species during nucleation. Density functional theory calculations additionally support the formation of these species as well as predicted metal oxide to fluoride conversion. Residual gas analysis revealed reaction by-products, and the combined experimental and computational results provided insights into proposed nucleation surface reactions. With additional ALD cycles, Fourier transform infrared spectroscopy indicated steady film growth after ∼13 cycles at 200 °C. XPS revealed that higher deposition temperatures resulted in a higher fraction of MoS 2 within the films. Deposition temperature was found to play an important role in film morphology with amorphous films obtained at 200 °C and below, while layered films with vertical platelets were observed at 250 °C. These results provide an improved understanding of MoS 2 nucleation, which can guide surface preparation for the deposition of few-layer films and advance MoS 2 toward integration into device manufacturing.