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Abstract Lightweight energy storage devices are essential for developing compact wearable and distributed electronics, and additive manufacturing offers a scalable, low‐cost approach to fabricating such devices with complex geometries. However, additive manufacturing of high‐performance, on‐demand energy storage devices remains challenging due to the need for stable, multifunctional nanomaterial inks. Herein, the development of 2‐dimensional (2D) titanium carbide (Ti₃C₂T_xMXene) ink that is compatible with aerosol jet printing for energy storage applications is demonstrated. The developed MXene ink demonstrates long‐term chemical and physical stability, ensuring consistent printability and achieving high‐resolution prints (≈45 µm width lines) with minimal overspray. The high‐resolution aerosol‐jet printed MXene supercapacitor achieves an areal capacitance of 122 mF cm⁻²and a volumetric capacitance of 611 F cm⁻³, placing them among the highest‐performing printed supercapacitors reported to date. These findings highlight the potential of aerosol jet printing with MXene inks for on‐demand, scalable, and cost‐effective fabrication of printed electronic and electrochemical devices. 

Recent advances in graphene-based electroanalytical biodevices: different methods for graphene synthesis, functionalization, device fabrication, and transduction mechanisms are discussed for various healthcare applications. 

Pseudomonas aeruginosa(P. aeruginosa) is a phenazine-producing pathogen recognized for its biofilm-mediated antibiotic resistance, showing up to 1000 times higher resistance compared to planktonic cells. In particular, it is shown that a phenazine called pyocyanin promotes antibiotic tolerance inP. aeruginosacultures by upregulating efflux pumps and inducing biofilm formation. Therefore, real-time study of phenazine production in response to antibiotics could offer new insights for early detection and management of the infection. Toward this goal, this work demonstrates real-time monitoring ofP. aeruginosacolony biofilms challenged by antibiotics using electrochemical sensors based on direct laser functionalization of laser induced graphene (LIG) with gold (Au) nanostructures. Specifically, two routes for functionalization of the LIG electrodes with Au-containing solutions are studied: electroless deposition and direct laser functionalization (E-Au/LIG and L-Au/LIG, respectively). While both methods show comparable sensitivity (1.276 vs 1.205μAμM⁻¹), E-Au/LIG has bactericidal effects which make it unsuitable as a sensor material. The effect of antibiotics (gentamicin as a model drug) on the production rate of phenazines before (i.e., in planktonic phase) or after biofilm formation is studied. The sensor data confirms that theP. aeruginosabiofilms are at least 100 times more tolerant to the antibiotic compared to planktonic cells. The biosensors are developed using a scalable and facile manufacturing approach and may pave the way toward simple-to-use antibiotic susceptibility testing devices for early infection diagnosis and real-time study of antibiotic resistance evolution. 

For continual scaling in microelectronics, new processes for precise high volume fabrication are required. Area-selective atomic layer deposition (ASALD) can provide an avenue for self-aligned material patterning and offers an approach to correct edge placement errors commonly found in top-down patterning processes. Two-dimensional transition metal dichalcogenides also offer great potential in scaled microelectronic devices due to their high mobilities and few-atom thickness. In this work, we report ASALD of MoS2 thin films by deposition with MoF6 and H2S precursor reactants. The inherent selectivity of the MoS2 atomic layer deposition (ALD) process is demonstrated by growth on common dielectric materials in contrast to thermal oxide/ nitride substrates. The selective deposition produced few layer MoS2 films on patterned growth regions as measured by Raman spectroscopy and time-of-flight secondary ion mass spectrometry. We additionally demonstrate that the selectivity can be enhanced by implementing atomic layer etching (ALE) steps at regular intervals during MoS2 growth. This area-selective ALD process provides an approach for integrating 2D films into next-generation devices by leveraging the inherent differences in surface chemistries and providing insight into the effectiveness of a supercycle ALD and ALE process.