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In this work, a 25 inch (400 × 500 mm) transparency-adjustable mini-LED (TA-MLED) display is constructed of a transparent mini-LED (T-MLED) screen and an electrochromic (EC) shutter. The shutter shows a high transmittance of 86.5% with imperceptible color shift, enabling a perfect vision experience for see-through application. Furthermore, the response speed of the shutter is accelerated by optimal designs in splicing and driving. The coloring time is 55 s, and bleaching time is 36 s. Transmittance of the TA-MLED could be modulated from 3% to 60%. The transparency-adjustable property extends availability of the see-through display screens under strong light irradiations. The T-MLED’s color gamut in CIE 1976 shrinks from 145.1% sRGB to 3.6% sRGB with 5161 cd/m2 of backside illumination, and is significantly enhanced to 83.5% sRGB with the active EC shutter.

High-capacity anode materials for lithium ion batteries (LIBs), such as Ge, generally suffer tremendous volume changes, as a result of the conversion reaction mechanism with Li, severely impede the high rate and cycling performance toward their practical application. In this article, we demonstrate a general LIBs Ge composites electrodes fabrication method using electrodeposition from room temperature ionic liquid. Our process is capable of forming composites electrodes with carbon nanotubes (CNTs), reduced graphene oxide (RGO), poly (3,4-ethylenedioxythiophene) (PEDOT), without the additives and conductive agents. During the electrodeposition process, Ge nanoparticles are integrated into the substrate network. Benefiting from the porosity, conductive network and mechanical stability constructed by interpenetrated compound layers, the hybrid system synergistically enhances the intrinsic properties of each component, yet is robust and flexible. The Ge/CNTs, Ge/RGO and Ge/PEDOT composites retain capacities of ∼851, 1212, and 1300 mAh/g after 200 cycles at 0.1 C. SEM analysis suggests that Ge/PEDOT composites have flower-like hierarchically porous structure, during cycling this structure transforms into a porous network, which can mitigate the physical strains during the Li uptake/release process, and increase the interfacial contact area with organic electrolyte. Consequently, the Ge/PEDOT composites demonstrate greatly enhanced rate capability without obvious capacity fading at high rate of up to 5 C.

Electrochromic (EC) materials have the ability to change their optical properties when exposed to a low electrical voltage. They have found a wide range of applications in smart windows, low-power displays, and spacecraft thermal control. To improve the practical applicability of EC materials, rational design and exploration of their architectures play a crucial role. Among various architectures, forms of inverse opal structure including two dimensionally and three dimensionally ordered macroporous structure (2DOM and 3DOM) exhibit outstanding and specific performance. In this review, several examples of 2DOM and 3DOM EC materials with detailed preparation methods are presented, followed by a detailed discussion of various aspects in ordered macroporous structural EC films, including common features, structure transition and photonic band gap tuning. In addition, the typical five layered design for the EC material-based device is given, as the device is of the most importance in researches as well as applications. Finally, conclusions and outlook are provided at the end of this review.

Innovative WO3·2H2O/PEDOT films with strong adhesion of the electrochromic layer and the substrate were fabricated. A WO3·2H2O/PEDOT electrochromic layer can be firmly fixed to an ethylene vinyl acetate/polyethylene terephthalate (EVA/PET) electrode using Ag as the conductive layer by a transient heating method. The electrochromic film is mechanically robust and can be twisted, folded and crumpled without performance degeneration. Improved performance has been realized by WO3·2H2O/PEDOT films compared with WO3·2H2O films due to the excellent electrical conductivity of PEDOT, including a higher of Li-ion diffusion coefficient (1.1×10−9 cm2 s−1), faster response time (2.6 s for bleaching time and 4.4 s for coloration time), higher color efficiency (180.2 cm2 C−1) and larger transmittance modulation (63.1%) at 956 nm. The results are very promising for the next generation of deformable or implantable hidden message displays and wearable smart clothes applications.

3D MoO3/PANI hybrid nanosheet networks were fabricated via hydrothermal, freeze-drying and electropolymerization methods. The structure, morphology, optical and electrochemical properties of the hybrid material were characterized using scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical measurements. It was found that the conductivity of the 3D MoO3 nanosheet networks was enormously enhanced by introducing PANI. The 3D MoO3/PANI hybrid nanosheet networks show a complementary dual-electrochromic effect (ranging from light yellow to purple then dark blue), fast switching speed of bleached and colored states (0.9 and 1.0 s, respectively), superior coloration efficiency and better cycling stability. The results demonstrate that optical and electrochemical properties of 3D MoO3/PANI hybrid nanosheet networks were improved compared to those of 3D MoO3 nanosheet networks. The unique inorganic–organic hybrid nanosheet networks can be used as effective electrode materials in the optical–electrochemical field.

Since oxidation and reduction reactions mainly take place on surfaces, enlarging the specific surface of redox materials is the key to achieving excellent electrochemical performance. In this work, by using silica monolayer colloidal crystal templates (MCCTs), a nanostructured Fc(COCH3)2 film is prepared successfully, and such a nanostructure could exhibit the following unique electrochemical properties: the MCCTs could impede the aggregation tendency of Fc(COCH3)2 and possess high electrochemical activity; Fc(COCH3)2 enlarges the contact area and offers more active sites and faster electronic transmission channels. The structure, optical and electrochemical properties of the nanostructured Fc(COCH3)2 were tested and then compared with those of compact Fc(COCH3)2 films to evaluate the role of the nanoarchitecture. The unique structure design of the Fc(COCH3)2 film enables outstanding performance, showing a large transmittance change (ΔT) of 37% at 550 nm when switched between 0.5 V and -2.5 V, which is approximately ninefold higher than that of the compact Fc(COCH3)2 film (approximately 4%). Response times of coloration and bleaching are found to be only 16.15 s and 5.56 s. Furthermore, the nanostructured Fc(COCH3)2 film shows much better cycling stability than the compact one. The results indicate that the nanostructure could significantly improve the electrochemical performance of the Fc(COCH3)2 film due to the increase in electrochemical active sites and the enhancement of the "D-to-A" redox switch of ferrocene.

Here, we developed a novel and facile approach to fabricating TiO 2 Nanotubes Membranes (TNMs) with thicknesses between 539 and 1930 nm. These were detached from a Ti substrate through immersion in water, followed by adhesion to a conducting fluorine-doped tin oxide (FTO) glass using an adhesion layer and annealing in order to form an anatase crystalline structure for transparent electrochromic applications. The possible mechanism of the TNM separation process in deionized water was evaluated using contact angle analysis, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The TNM electrodes exhibited remarkable electrochromic performances, combining high coloration contrast with a transmittance of 65% in the visible spectrum and good cycle stability, which was maintained at 88.2% for initial optical modulation after 1000 cycles. These TNMs may advance the design of efficient and low-cost electrodes operating in the visible light spectrum that are intended for photo electrochemical applications.

Poly(3-methylthiophene) (PMeT) is considered a promising conductive polymer for applications in electrochromic displays due to its red to blue multi-color switch as well as low cost. However, the non-uniformity of the films caused by high electrochemical polymerization potentials during electrodeposition and the rapid electrochemical stability decay caused by weak adhesion limits its practical application. In this study, a new pre-nucleation electrodeposition method is developed to synthesize PMeT film. The nucleation grown progress is investigated by electrochemical fitting tests and scanning electron microscopy. Compared with a directly grown film, the pre-nucleation PMeT film presents excellent electrochromic EC transmittance modulation of 75% at wavelength of 1050nm, and sustains a transmittance modulation of about 91 % after 400 cycles. This was the result of enhanced uniformity and adhesion from the pre-nucleation method. The surface uniformity and roughness of PMeT films were analyzed by optical microscopy and atomic force microscopy measurements. After controlling thickness using this method, the PMeT films exhibited multiple transmittance change and red–green–blue color change.

Neoproterozoic paleogeography of the Cathaysia Block of South China is directly linked to the formation of Rodinia, its break-up, and the subsequent amalgamation of Gondwana. Two diamictite units occur in the Neoproterozoic sedimentary successions on the western margin of Cathaysia Block. In combination with our detrital zircon U-Pb dating results and corrected chemical weathering index data (CIAcorr), these units coincide with the global Sturtian and Marinoan glaciations. Late Tonian to early Ediacaran sedimentary rocks from western Cathaysia contain abundant late Mesoproterozoic to early Neoproterozoic (1150–870 Ma) and some mid-Neoproterozoic (800–720) detrital zircons. Paleocurrent data indicate sediment transport to the northwest. The timing and character of the ages of detrital zircons match the records of North India and East Antarctica, indicating that the Cathaysia Block received detritus from Gondwana. Thus, South China lay adjacent to northern Gondwana since at least 720 Ma, and possibly considerably earlier.

In this article, we report the preparation of a TiO2 nanotube array (TNA) film used as a transparent electrochromic material and a TNA/polyaniline patterned hybrid electrochromic film utilized as an information display material. The TNA film was fabricated by an anodizing process, and a surface patterned TNA with extreme wettability contrast (hydrophilic/hydrophobic) on a TNA surface through self-assembly (SAM) and photocatalytic lithography is fabricated. Then the TNA/polyaniline hybrid film was prepared by electrodeposition of aniline in an aqueous solution. Finally, the electrochromic properties of the TNA film and the TNA/polyaniline hybrid film were investigated. Compared with neat TNA film and polyaniline (PANI) films, the hybrid film shows a much higher optical contrast in the near infrared range. The TNA/polyaniline hybrid film shows higher coloration efficiencies of 24.4 cm2 C-1 at a wavelength of 700 nm and 17.1 cm2 C-1 at a wavelength of 1050 nm compared to the TNA coloration efficiency. The color switching time (20.9 s or 22.9 s) of TNA/polyaniline is faster than TNA.

A novel electrochromic device (ECD) was constructed with two same-material electrochromic layers deposited on indium-tin oxide (ITO)-coated glass substrates, a double-sided ITO-coated glass substrate, and a gel electrolyte. The device exhibited fast coloration/bleaching response and significantly enhanced optical modulation and coloration efficiency compared to traditional ECDs.

For the first time, a crystalline-amorphous double-layered NiOx film has been prepared by reactive radio frequency magnetron sputtering, which has exhibited improved electrochemical cycling durability, whereas other electrochromic parameters have been maintained at the required level, i.e. the short coloration/bleaching time (0.8s/1.1s) and an enhanced transmittance modulation range (62.2%) at the wavelength of 550 nm. Besides this, the double-layered film has shown the best reversibility as compared with amorphous and crystalline single-layer films.

In this paper, three-dimensionally ordered macroporous (3DOM) poly(3,4-ethylenedioxythiophene) (PEDOT) films were electropolymerized from an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim]PF6 ). The electrochromic performances of the 3DOM PEDOT films were studied. The 3DOM films exhibited high transmittance modulation (41.2 % at λ=580 nm), high ionic fast switching speeds (0.7 and 0.7 s for coloration and bleaching, respectively), and enhanced cycling stability relative to that exhibited by the dense PEDOT film. The relationship between the declining behavior of the transmittance modulation and the nanostructure of the film was investigated. A three-period decay process was proposed to understand the declining behavior. The 3D interconnected macroporous nanostructure is beneficial for fast ion and electron transportation, high ion accessibility, and maintenance of structure integrity, which result in enhanced cycling stability and fast switching speeds.

Au–Ni–V filler alloys with different vanadium contents were designed to braze Si 3 N 4 ceramic at 1373 K for 30 min, and the microstructures of brazing seams were investigated by SEM and TEM. When the Au–Ni–V filler alloy contains 5 at.% V, round-like Ni[Si, V, Au] precipitates form in the Au[Ni] solid solution matrix and a VN reaction layer with 0.5 μm thickness appears on Si 3 N 4 interface. When the V content increases to 10 at.%, a new polygonal Ni 2 SiV 3 phase occurs in the seam, and the Ni[Si, V, Au] precipitate coarsens and VN layer thickens. With increase of V contents to 15 and 20 at.%, laminar Ni[Au] and polygonal Ni 3 V precipitates form. With 25 at.% V content in the filler alloy, the Ni 2 SiV 3 and Ni 3 V precipitates distribute homogenously in the brazing seam. These microstructure evolutions were attributed to the reaction between Si 3 N 4 and vanadium, which forms VN reaction layer and releases Si into the molten alloy.

By using Au58.74Ni36.50V4.76 at.% filler alloy, a reliable Si3N4/Si3N4 joint was brazed at 1,423 K for 60 min in vacuum. The microstructure of the joint was investigated and analyzed by scanning electron microscope with energy dispersive spectroscopy, transmission electron microscopy, and X-ray diffraction. The results indicate that the joint consists of three main phases: a continuous VN reaction layer between filler alloy and Si3N4 ceramic; an Au[Ni] solid solution as the matrix of the joint; and Ni[Si,V] solid solution particles distributed homogeneously in the Au[Ni] solid solution. The mechanism of formation of the interfacial structure is discussed.