Man-made glues often fail to stick in wet environments because of hydration-induced softening and dissolution. The wound healing process of a tunicate inspired the synthesis of gallol-functionalized copolymers as underwater adhesive. Copolymers bearing three types of phenolic groups, namely, phenol, catechol, and gallol, were synthesized via the methoxymethyl protection/deprotection route. Surprisingly, the newly synthesized copolymers bearing gallol groups exhibited stronger adhesive performances (typically 7× stronger in water) than the widely used catechol-functionalized copolymers under all tested conditions (in air, water, seawater, or phosphate-buffered saline solution). The higher binding strength was ascribed to the tridentate-related interfacial interaction and chemical cross-linking. Moreover, gallol-functionalized copolymers adhered to all tested surfaces including plastic, glass, metal, and biological material. In seawater, the performance of gallol-functionalized copolymer even exceeds the commercially available isocyanate-based glue. The insights from this study are expected to help in the design of biomimetic materials containing gallol groups that may be utilized as potential bioadhesives and for other applications. The results from such a kind of comparable study among phenol, catechol, and gallol suggests that tridentate structure should be better than bidentate structure for bonding to the surface.

Biological nanochannels control the movements of different ions through cell membranes depending on not only those channels' static inherent configurations, structures, inner surface's physicochemical properties but also their dynamic shape changes, which are required in various essential functions of life processes. Inspired by ion channels, many artificial nanochannel‐based membranes for nanofluidics and biosensing applications have been developed to regulate ionic transport behaviors by using the functional molecular modifications at the inner surface of nanochannel to achieve a stimuli‐responsive layer. Here, the concept of a dynamic nanochannel system is further developed, which is a new way to regulate ion transport in nanochannels by using the dynamic change in the curvature of channels to adjust ionic rectification in real time. The dynamic curvature nanochannel‐based membrane displays the advanced features of the anomalous effect of voltage, concentration, and ionic size for applying simultaneous control over the curvature‐tunable asymmetric and reversible ionic rectification switching properties. This dynamic approach can be used to build smart nanochannel‐based systems, which have strong implications for flexible nanofluidics, ionic rectifiers, and power generators.

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Polyphenols, which by the Quideau definition are plant-derived chemicals with two or more phenolic groups, have attracted interest because of their antioxidant activity, adsorption on universal substrates, and biocompatibility. Most polyphenols include gallol groups in their chemical structures, which has inspired us to synthesize gallol-functionalized polymers. We report the reversible addition–fragmentation chain transfer polymerization of 3,4,5-trimethoxystyrene using cyanomethyl dodecyl trithiocarbonate as the chain transfer agent. This method produces well-defined polymers with a wide range of molecular weight (from 5.4 to 53.4 kg mol–1) and low polydispersity index (M w/M n < 1.3). Subsequent demethylation of poly­(3,4,5-trimethoxystyrene) (PTMS) yields poly­(3,4,5-trihydroxystyrene) (polyvinylgallol, PVGal). These newly synthesized polymers exhibit greater antioxidant activities than widely used catechol-functionalized polymers based on the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), 2,2′-azinobis­(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and oxygen radical absorbance capacity (ORAC) methods. Also, PVGal showed better adsorption properties on metals and SiO2 substrates than those of the other phenolic polymers. Given these high antioxidant and adsorption properties, the effective use of gallol-funcationalized polymers in biomaterials is expected.

Nanochannels offer a variety of significant advantages for innovative applications, such as biosensing, filtering, and energy utilization. In this Perspective, we highlight the interface design and applications of nanochannels for energy utilization and discuss further challenges in the development of nanochannels for energy conversion, energy conservation, and energy recovery.

The properties of nanomaterials are highly dependent on their size, shape and composition. Compared with zero-dimensional nanoparticles, the increased dimension of a one-dimensional silver nanowire (AgNW/Ag NW) leads to extra challenges on synthesizing it with controllable sizes. Here, a convenient way for the synthesis of AgNWs with tunable sizes has been developed simply by adjusting the amount of salt additives, i.e., ferric chloride (FeCl), or Fe(NO) & KCl. The average diameter and length of nanowires are readily tailored within 45-220 nm and 10-230 μm, respectively. The distinctive roles of Fe and Cl played during the growth stages of Ag NWs were revealed by comparative experiments and a heterogeneous nucleation model with the assistance of oxidative etching was proposed to elucidate the growth mechanism. Afterwards, transformations in XRD patterns from nanometer-size effects and quantitative relation for size-dependent peak wavelength of surface plasmon resonances (SPRs) in UV-vis spectroscopy of these nanowires were studied. In addition, as transparent conductive materials (TCMs), these metal nanowires were utilized to fabricate transparent conductive films (TCFs), and the effects of their diameters and lengths were elucidated. Very/ultra-long nanowires with a high aspect ratio up to 1600 achieved impressive properties of R = 12.4 ohm sq at T% = 90.1% without any post treatment. This facile method for the size-tunable growth of uniform AgNWs with high yield is attractive and ready to be home-made, which is believed to promote research in their potential applications, especially in optoelectronic devices and flexible electronics.

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This article reviews the development of the design of soft interfaces in electrokinetic energy conversion and their applications.