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Protecting an anode from deterioration during charging/discharging has been seen as one of the key strategies in achieving high-performance lithium (Li)–O2 batteries and other Li–metal batteries with a high energy density. Here, we describe a facile approach to prevent the Li anode from dendritic growth and chemical corrosion by constructing a SiO2/GO hybrid thin layer on the surface. The uniform pore-preserving layer can conduct Li ions in the stripping/plating process, leading to an effective alleviation of the dendritic growth of Li by guiding the ion flux through the microstructure. Such a preservation technique significantly enhances the cell performance by enabling the Li–O2 cell to cycle up to 348 times at 1 A·g–1 with a capacity of 1000 mA·h·g–1, which is several times the cycles of cells with pristine Li (58 cycles), Li–GO (166 cycles), and Li–SiO2 (187 cycles). Moreover, the rate performance is improved, and the ultimate capacity of the cell is dramatically increased from 5400 to 25,200 mA·h·g–1. This facile technology is robust and conforms to the Li surface, which demonstrates its potential applications in developing future high-performance and long lifespan Li batteries in a cost-effective fashion.

The noble metal nanoparticle has been widely utilized as a plasmonic unit to enhance biosensors, by leveraging its electric and/or optical properties. Integrated with the "flexible" feature, it further enables opportunities in developing healthcare products in a conformal and adaptive fashion, such as wrist pulse tracers, body temperature trackers, blood glucose monitors, etc. In this work, we present a holistic review of the recent advance of flexible plasmonic biosensors for the healthcare sector. The technical spectrum broadly covers the design and selection of a flexible substrate, the process to integrate flexible and plasmonic units, the exploration of different types of flexible plasmonic biosensors to monitor human temperature, blood glucose, ions, gas, and motion indicators, as well as their applications for surface-enhanced Raman scattering (SERS) and colorimetric detections. Their fundamental working principles and structural innovations are scoped and summarized. The challenges and prospects are articulated regarding the critical importance for continued progress of flexible plasmonic biosensors to improve living quality.

Autonomous shape transformation is key in developing high-performance soft robotics technology; the search for pronounced actuation mechanisms is an ongoing mission. Here, we present the programmable shape morphing of a three-dimensional (3D) curved gel structure by harnessing multimode mechanical instabilities during free swelling. First of all, the coupling of buckling and creasing occurs at the dedicated region of the gel structure, which is attributed to the edge and surface instabilities resulted from structure-defined spatial nonuniformity of swelling. The subsequent developments of post-buckling morphologies and crease patterns collaboratively drive the structural transformation of the gel part from the "open" state to the "closed" state, thus realizing the function of gripping. By utilizing the multi-stimuli-responsive nature of the hydrogel, we recover the swollen gel structure to its initial state, enabling reproducible and cyclic shape evolution. The described soft gel structure capable of shape transformation brings a variety of advantages, such as easy to fabricate, large strain transformation, efficient actuation, and high strength-to-weight ratio, and is anticipated to provide guidance for future applications in soft robotics, flexible electronics, offshore engineering, and healthcare products.

Intelligent polymers with tough networks are of considerable significance for thedevelopment of highly proficient polymer science and technology. In this work, polymeric elastomers with integrated stretchable and self-healable characteristics were designed by cross-linking hyperbranched polymers with flexible segments. The hyperbranched polymer with multiple terminal groups provided various cross-linking points, so that mechanically robust networks could be achieved. Driven by the reversibility of imine and disulfide bonds employed, the elastomers exhibited good self-healing property and the healing efficiency reached up to 99% under ambient environments. Furthermore, the dynamic reversibility of the polymers was investigated at molecular level. The imine and disulfide bonds were incorporated into the networks to construct soluble and recyclable hyperbranched polymer with pH and redox responsiveness via A2+B3 approach and Schiff base polymerization. The polymers containing imine bonds could complete the polymerization–depolymerizationtransition and undergo reversible cycles for several times through changing pH. Moreover, in the presence of disulfide bonds, the polymers were provided with redox cleavage property triggered by dithiothreitol. This study may provide new opportunities for the design and application of intelligent polymers with tough networks through regulating topological structures.

In this study, a packed-bed dielectric barrier discharge reactor was built for the removal of biomass gasification tar. Two kinds of packing materials, glass pellets and a Ni/?-Al2O3 catalyst, were employed for the plasma-alone process and the plasma catalytic process, respectively. Toluene was used as the tar surrogate, and five typical gas combinations, N2, N2 + CO2, N2 + CO2 + CO, N2 + CO + H2, and simulated gasification gas (SGG), were selected as carrier gases. The effects of the main components of the gasification gas on toluene removal under plasma and/or catalysis treatment were studied. The results indicated that the highest removal efficiency in the plasma-alone process was achieved in the N2 atmosphere, and the addition of H2, CO, or CO2 to N2 led to a decrease in the removal performance. When Ni/?-Al2O3 was introduced into the plasma process, the best removal efficiency was obtained in the N2 + CO2 atmosphere. However, the positive effect of CO2 on toluene removal switched to a negative effect when CO2 coexists with CO and H2 in the gas mixture. In addition, both the terminating effect at low temperature and the occurrence of methanation induced by CO at high temperature could significantly inhibit the removal of toluene in the plasma catalytic process. Typically, in the SGG atmosphere, the highest toluene removal efficiencies under plasma-alone, catalysis-alone, and plasma catalysis treatments were 33.5, 38.6, and 92.5%, respectively. Furthermore, no CN-containing or O-containing compounds were identified as the major by-products in the plasma catalytic process, which is significantly different from what was observed in the plasma-alone process. Moreover, a detailed mechanism of toluene removal under plasma and plasma catalysis treatment was proposed after the analysis of gas and liquid products.

In this study, a packed-bed dielectric barrier discharge (DBD) reactor was developed to investigate the removal of biomass tar in a fuel gas atmosphere. Toluene was used as the tar surrogate, and the catalyst used was a Nickel-based catalyst (Ni/γ-Al2O3) because of its high activity and low cost. In addition, another two kinds of packing materials (glass pellets and γ-Al2O3 pellets) were employed to make a comparison with the Ni/γ-Al2O3 catalyst. The research has focused on the removal efficiency of toluene and the effects of carrier gas, reaction temperature, Ni loading, and concentration of toluene. The results indicated that two supplementary packing materials could not realize an effective removal of toluene. On the contrary, Ni/γ-Al2O3 combined with plasma showed a significant synergetic effect and hence a great toluene removal potential. On one hand, the removal efficiency initially decreased within the temperature range of 200–300 °C and then significantly increased within the temperature of 300–400 °C during plasma-catalytic process. At the optimal temperature of 400 °C, the toluene removal efficiency could reach the maximum values of 80.2%, 91.7%, and 100.0% when the Ni loading was 3, 5, and 10 wt %, respectively. On the other hand, an increase in the inlet toluene concentration slightly reduced removal efficiency but increased the energy efficiency, reaching the highest value of 16.8 g/kWh. The introduction of plasma enhanced the methanation reaction of the fuel gas occurring in the catalytic process, which was favorable at high temperatures. Based on these findings, the mechanisms and pathways of toluene destruction in the plasma-catalytic process were proposed and elucidated.

The Seebeck coefficient, thermoelectric power factor, electrical conductivity, and electronic thermal conductivity of the orthorhombic Pbnm phase of SrRuO3 are studied comprehensively by combining first-principles density functional calculations and Boltzmann transport theory. The influence of exchange-correlation functional on the Seebeck coefficient is carefully investigated. We show that the best agreement with experimental data is achieved when SrRuO3 is described as being at the limit of a half-metal. Furthermore, we analyze the role of individual symmetry-adapted atomic distortions on the Seebeck coefficient, highlighting a particularly strong sensitivity to R-4(+) oxygen rotational motions, which may shed light on how to manipulate the Seebeck coefficient. We confirm that the power factor of SrRuO3 can only be slightly improved by carrier doping. Our results provide a complete understanding of the thermoelectric properties of SrRuO3 and an interesting insight on the relationship between exchange-correlation functionals, atomic motions, and thermoelectric quantities.