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We prepared multicolor, dual-image, printed electrochromic displays (ECDs) based on three hybrid electrodes containing mesoporous titanium dioxide (TiO2) functionalized with various phosphonated viologens. When the hybrid electrodes are employed in ECDs, diverse colors (e.g., cyan, green, magenta, emerald, and yellow) are obtained depending on the electron affinity of the N-substituents of the viologen. The devices show fast switching speed (e.g., avg. coloration ∼ 2.0 s and bleaching ∼ 1.5 s) and high coloration efficiency (avg. ∼ 328.8 cm2/C), which is attributed to the large surface area of the hybrid electrode. We also introduced a tandem configuration by inserting double-sided fluorine-doped tin oxide electrode (dsFTO) between two hybrid electrodes to overcome the limitation of the achievable colors (one or maximum two) in a single cell. The dsFTO can serve as a counter electrode of both hybrid electrodes, allowing independent or simultaneous operation of each hybrid electrode through adjusting applied voltage. To extend the functionality of tandem ECDs, the patterned hybrid electrodes are fabricated using electrostatic-force-assisted dispensing printing and applied to ECDs. The resulting devices alternately exhibit two pieces of information in a variety of colors, in which the device operation is controllable in accordance with the direction of applied voltage and the combination of hybrid electrodes. The printed, tandem structured ECDs are expected to have high potential for next-generation transparent displays.

In this work, a CuO/Ag composite electrode was fabricated using precursor type ink. The hybrid ink contains both Ag and Cu precursors and fully decomposes at 150 °C in ambient atmosphere and was used to make a CuO/Ag electrode. The addition of the copper precursor to the silver ink resulted in an improvement of the electrocatalytic performance towards the reduction of hydrogen peroxide (H 2 O 2 ). The fabricated electrodes were used to make an amperometric sensor which showed a linear response in a wide range and a low detection limit of 4.0 μM (S/N = 3). Additionally, the sensor displayed good anti-interference properties, repeatability and stability.

Nowadays, stretchable, flexible and wearable strain sensors are becoming more and more important for their abilities to monitor human health and body motions. However, it still exists some challenges to develop a new type of strain sensor with high sensitivity, the properties of anti-harsh environments and multidirectional monitoring. Here, we put forward a flexible, multi-functional, wearable and conductive nanofiber composite (WCNC) strain senor with handy preparation method, consisting of elastic thermoplastic polyurethane (TPU) with decorated acid modified carbon nanotubes (ACNTs), coupled silver nanowires (AgNWs) and solidified polydimethylsiloxane (PDMS). The sequential decorations of ACNTs, AgNWs and PDMS enhance the conductivity, superhydrophobicity, and strain sensing performance of the TPU-based nanofibrous membrane. The WCNC (TPU/ACNTs/ AgNWs/ PDMS) possesses a quite low resistance about 1.22 Ω/cm2 (conductivity is up to 3506.8 S/m), superior superhydrophobicity (contact angle is up to 153.04°) and self-cleaning property. Furthermore, the WCNC strain sensor possesses high sensitivity and large working strain (gauge factor is nearly 1.36 × 105 with the working strain ranging from 38% to 100%), which illustrates that the WCNC has a quite large work strain under extremely high GF, and has never been reported before. On account of its outstanding sensing performance, the WCNC can be used to monitor the different movements of human bodies and simultaneously monitor sensor signals in multiple vertical directions, achieving more accurate results.

Most reported non-precious-metal catalysts for oxygen evolution reaction (OER) are composed of iron, cobalt, or nickel. Copper, on the other hand, is relatively neglected despite its versatility. In this paper, we describe a series of steps to enhance the OER efficiency of copper-based catalyst, including metal organic framework (MOF)-guided structure control, secondary metal doping, and nitridation. In particular, the effect of growth solvent on coordination kinetics and morphology of the precursor MOFs was studied in detail. The optimal MOF structure was further engineered with Fe doping followed by rapid microwave-assisted nitridation, resulting in CuFeN/CNT composite. Experimental results showed that all three engineering steps have significant impact on the enhanced OER efficiency. CuFeN/CNT composite with optimal Fe doping derived from urchin-shaped CuFeMOF exhibited a greatly enhanced OER performance comparable to that of precious metal catalyst, affording a current density as high as 236.3 mA at an overpotential of 420 mV (RuO2, 215.3 mA). Furthermore, excellent stability in alkaline media was observed during 1000 cycles and chronopotentiometric analysis for over 20 hours. We highlight that the entire synthesis protocol is environmentally benign and sustainable by employing microwave to enable rapid formation and conversion of the precursors with minimal energy consumption.

In search of inexpensive and efficient electrocatalyst for water electrolysis, three strategies to bring out the full potential of the most earth abundant transition metal, iron, are explored: MOF-templated morphology control, secondary metal incorporation, and nitrogen doping. This paper describes an ultrafast microwave-assisted synthesis of FeMo-MIL-88B followed by self-templated calcination via soft-urea path. The transformed 3D rod-shaped porous iron-molybdenum oxynitride (FeMoON) presents outstanding electrocatalytic performances in hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and overall water splitting. The FeMoON electrode affords high current densities of 850 mA cm−1 at an overpotential of merely 364 mV for OER and 750 mA cm−1 at an overpotential of 400 mV for HER. The overall water-splitting demeanor surpasses that of commercial noble metal pair in high current densities and shows potential for long-term stability.

In this work, a facile method is proposed for the fabrication of self-organized hierarchically porous carbon coated on carbon cloth. The method is based on the thermal treatment of potassium citrate gel, which is derived from mixture of citric acid and potassium hydroxide. The as-prepared porous carbon derived from citrate gel generally covers carbon cloth with fine morphological properties and the sample can be directly used as an electrode material for supercapacitor. In a three-electrode configuration, the optimized electrode exhibits a remarkable specific capacitance of 379.5F g−1 at a current density of 1 A g−1. In addition, a good cycle stability with capacity retention of 97% is achieved after 10,000 cycles at a current density of 10 A g−1. Moreover, a symmetric supercapacitor is prepared by using the as-prepared electrode. The supercapacitor shows a high energy density of 0.69 mWh cm−3 at a power density of 4.91 mW cm−3 and good cycle durability and mechanical flexibility. The porous carbon material reported in this work shows potential as electrode for flexible all-solid-state supercapacitors.

Excellent uniformity (∼1.5% RSD) in SERS signals was obtained from an Ag/GO decorated adhesive tape on a simple in-house cylindrical scanning system. The calibration curve for the quantitative analysis of CV shows reliable linearity ranging from 75 nM to 50 μM. This novel method is promising to be an adept tool for universal quantitative analysis and be used complementarily with the conventional Raman mapping method for a more time efficient and reliable analysis.

Electrochemical energy-storage devices are essential in our daily life to supply electricity in order to support electric vehicles, portable electronic devices and back-up power. Innovative researches on new versatile electrode materials are the foundation for the development of neoteric high-performance electrochemical energy-storage devices. Electrode materials with nanoscale size as well as unique morphologies often provide higher theoretical specific capacities than bulk materials. To date, salt powder assisted synthetic methods have been continuously investigated. This review reinforces our understanding of solid salt assisted synthetic methods to make them more sufficient and systematic, which promotes their widespread development and application, especially in the synthesis of nanostructured materials for electrochemical energy storage devices. This work reviews recent scientific advances involving solid salts as functional assistant for the preparations of nanostructured materials with high porosity, as well as their applications in electrochemical energy storage devices. Furthermore, this review highlights that the optimization of the precursors as well as careful choice of salt is needed to fabricate such nanomaterials successfully. Finally, we present a vision for the future development of optimal electrochemical energy storage devices with excellent performances derived from their unique nanostructures with the assistance of solid salts which possess infinite possibilities.

Uniform nanoparticles have shown to hold great potential in many different fields. As a result, many resources have been devoted to the search for a general synthesis of uniform nanoparticles, which has led to the proliferation of solution-based methods. However, some of these techniques are inherently difficult to scale up and are unable to meet future industry needs. Additionally, since the synthesis temperature of these methods can only go as high as the evaporation point of the solvent, they are not compatible with the high temperatures required to obtain certain desired properties such as high crystallinity. Recently, solventless methods have gained considerable attention since they are relatively fast and require no expensive or toxic solvents. Inorganic salt powder can be used as separation medium to prevent aggregation and sintering by keeping the as-prepared nanoparticles or precursor materials physically separated. This review surveys the use of inorganic salts in solventless techniques for the annealing or direct synthesis of uniform nanoparticles.

The purpose of this study is to relate Sir Launfal to fourteenth century England and to explore the contemporary re-conceptualization of a knight presented in the poem. My argument is that Sir Launfal is a portrait of a knight, not ensconced in the idealized setting as in Marie de France’s poem, but frequently found among fourteenth century English nobility. Appropriating inherited literary materials and stock motifs of the genre, Chestre demystifies the ideal of knighthood, de-idealizes romantic love and discloses the cohesiveness of wealth and knighthood, mainly through his own insertions of episodes that serve to widen the prospect of the poem from an individual knight to the society in which he is entwined in the social networks and the value system shared by its members. “Materialistic” or “bourgeois” features found in the poem and criticized so far are symptomatic or reflective of the state of affairs in Chestre’s age, such as the sumptuary laws, visual display culture of the nobility, inheritance of lands through heiresses, and a series of redistribution of estates from 1327 to 1337. In conclusion, Sir Launfal is not a deplorable degradation of Lanval, nor should it be evaluated by the standard which sets the twelfth century French romances as a model. Rather, it should be viewed as a poem born in fourteenth-century England?brimming with social, political and social changes within and without the court?intended to depict a knight of this age.