Seawater batteries (SWBs) are a type of sodium-air batteries that use abundant seawater as the source of the catholyte. A cathode current collector in traditional SWBs is composed of titanium (Ti) and carbon-based current collectors. The high contact resistance between Ti and carbon-based current collectors as well as the slow kinetics of oxygen evolution and reduction reactions increase the overpotential, resulting in side reactions such as carbon corrosion. To enhance the performance of SWBs, previous studies have focused on carbon current collectors, catalysts, and polymer binders, while ignoring the importance of Ti. In this study, a facile carbon diffusion technique is employed to successfully form titanium carbide (TiC) on the surface of Ti. SWBs with engineered Ti demonstrate considerably improved performance (four times higher cycling stability, 30% increased power performance, 40% reduced voltage gap) in relation to those with pristine Ti. This significantly improved electrochemical performance is found to be attributable to the prevention of carbon corrosion due to i) the reduction of contact resistance (owing to rough TiC surface) and ii) the electrocatalytic effect of TiC. Finally, engineered Ti is applied to large-area SWBs and its potential applicability in energy storage systems is confirmed.

Owing to the rise in global population and living standards, waste treatment has inevitably become a critical issue for a sustainable environment. In particular, for an effective recycling process, it...

The development of flexible electronic technology has led to convenient devices, including foldable displays, wearable, e‐skin, and medical devices, increasing the need for flexible adhesives that can quickly recover their shape while connecting the components of the device. Conventional pressure sensitive adhesives (PSAs) can improve recoverability via crosslinking, but often have poor adhesive strength. In this study, new types of urethane‐based crosslinkers are synthesized using m‐xylylene diisocyanate (XDI) or 1,3‐bis(isocyanatomethyl)cyclohexane (H6XDI) as a hard segment, and poly(ethylene glycol) (PEG) group as a soft segment. The PSA with the synthesized H6XDI‐PEG diacrylate (HPD) demonstrates a significantly improved recoverability compared to XDI‐PEG diacrylate and a conventional crosslinker 1,6‐hexanediol diacrylate (HDDA) while maintaining high adhesion strength (≈25.5 N 25 mm−1). The excellent recovery property of the PSA crosslinked with HPD is further confirmed by 100k folding tests and 10k multi‐directional stretching tests exhibiting high folding and stretching stability. PSA with HPD also shows high optical transmittance (> 90%) even after 20% straining, suggesting its applicability in fields that simultaneously require high flexibility, recoverability, and optical clarity such as foldable displays.

Graphene plasmons have attracted enormous research interest due to their dynamic tunability and the extreme field confinement they provide. However, despite their popularity, most studies revolving around graphene plasmons have been restricted to room temperature, leaving unconsidered important tunability knob. In this work, we experimentally investigate the temperature-dependent plasmonic properties of graphene nanoresonators with varying widths on SiO2 substrate by infrared transmission spectroscopy. As temperature drops from 300 to 100 K, the intensity of the graphene plasmon resonance peak increases up to 76%, and the amount of enhancement decreases with increasing carrier concentration and decreasing resonator width. We attribute the enhancement of graphene plasmon resonance to an additional hole doping of Δp = 1.37 × 1012 cm–2 associated with cooling and reduced plasmon damping due to the suppression of phonon-mediated scattering channels. Our results uncover the significance of temperature effects that can be exploited in graphene-based tunable plasmonic devices operating at low temperatures.