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As a new class of materials, implantable flexible electrical conductors have recently been developed and applied to bioelectronics. An ideal electrical conductor requires high conductivity, tissue-like mechanical properties, low toxicity, reliable adhesion to biological tissues, and the ability to maintain its shape in wet physiological environments. Despite significant advances, electrical conductors that satisfy all these requirements are insufficient. Herein, a facile method for manufacturing

Aqueous zinc metal batteries (AZMBs) are emerging energy storage systems that are poised to replace conventional lithium-ion batteries owing to their intrinsic safety, facile manufacturing process, economic benefits, and superior ionic conductivity. However, the issues of inferior anode reversibility and dendritic plating during operation remain challenging for the practical use of AZMBs. Herein, a gel electrolyte based on zwitterionic poly(sulfobetaine methacrylate) (poly(SBMA)) dissolved with

Gold nanoparticles (AuNPs) were assembled with high density onto multi-walled carbon nanotubes, which were functionalized with zwitterionic poly(imidazoliumsulfonate). The AuNP/zwitterionic CNT hybrids exhibited decent electrocatalytic activity in oxygen reduction reaction as the AuNP-based catalysts.

Thermoresponsive poly(<i>N</i>-isopropylacrylamide) (PNIPAAm) hydrogels have been attracting attention in a variety of functional materials, such as biomaterials, because they exhibit a volume phase transition phenomenon near physiological temperatures. However, the slow kinetics and small volume shrinkage of bulk PNIPAAm hydrogels upon heating greatly limit their practical application. Here, we report PNIPAAm hydrogels with phase-separated structures that exhibited ultrafast shrinking upon heat

Abstract An array of shear sensors is essential in tactile sensation as well as the pressure sensors. Surprisingly, however, the shear sensor array is rarely investigated mainly due to the structural complexity to measure the horizontal forces from various directions and also due to the mechanical softness required for preventing the slip of an object. Here, an array of small shear sensors that can recognize both shear force and shear rotational angle is fabricated. All the device components are

We report remarkable metal-free electrocatalytic activities of the imidazolium salt-functionalized ionic multi-walled carbon nanotubes (IM-f-MWCNTs) in the oxygen reduction reaction (ORR). The electrocatalytic activity can be attributed to the induced polarization of the π-electrons of CNTs, thus accelerating interfacial electron transfer. The zwitterionic MWCNTs functionalized with poly(vinylimidazolium sulfonate) have a more positive surface charge and exhibit a better electrocatalytic activit

In this study, we compared the responses of two different types of zwitterionic polymers (ZPs), polyvinylimidzole sulfobetaine (poly(SBVI)) and polymethacrylate sulfobetaine (poly(SBMA)) to Hofmeister anions. Although the anions of the two ZPs were the same as the sulfonate anions and only the types of their cations were different from each other, the aggregation behavior of each in the salt aqueous solution was remarkably different. Consequently, poly(SBVI) exhibited both salting-in and salting

Chemically synthesized PEDOT (poly(3,4-ethylenedioxythiophene)) nanomaterials, with various nanostructured morphologies as well as different intrinsic electrical conductivities and crystallinities, were compared as electrocatalysts for Co(III) reduction in dye-sensitized solar cells (DSSCs). Electrochemical parameters, charge transfer resistance toward the electrode/electrolyte interface, catalytic activity for Co(III)-reduction, and diffusion of cobalt redox species greatly depend on the morpho

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTReversible and Directional Control of Chemical Wave Propagation in a Hydrogel by Magnetic Migration through Liquid InterfacesEunjong LeeEunjong LeeDepartment of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, JapanMore by Eunjong Lee, Youn Soo Kim*Youn Soo KimDepartment of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Ja

Self-regulating hydrogels represent the next generation in the development of soft materials with active, adaptive, autonomous, and intelligent behavior inspired by sophisticated biological systems. Nature provides exemplary demonstrations of such self-regulating behaviors, including muscle tissue's precise biochemical and mechanical feedback mechanisms, and coordinated cellular chemotaxis driven by dynamic biochemical signaling. Building upon these natural examples, self-regulating hydrogels ar

E-mail: sanggi@ewha.ac.kr (S.-g. Lee), cmlee@ewha.ac.kr (C. Lee)Received July 6, 2011, Accepted July 27, 2011Key Words : Oxygen reduction, Palladium, Electrocatalyst, Ionic CNT, Fuel cellIonic liquids (ILs) have attracted an increasing amount ofinterest, owing to their high thermal and chemical stabilitywith considerable electric conductivity and wide electro-chemical windows.

Abstract Aqueous zinc ion batteries (AZIBs) have emerged as a promising next‐generation energy storage technology to replace lithium‐ion batteries. Recently, gel polymer electrolytes (GPEs), as a critical component of AZIBs, have garnered significant attention due to their potential to address challenges associated with conventional aqueous electrolytes, such as dendrite growth, corrosion, electrolyte evaporation, and leakage. However, the mechanical properties of hydrogels often remain suboptim