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A nanoporous BiVO4/TiO2/Ti film was successfully fabricated by electrodepositing a nanoporous BiOI film on nanoporous TiO2 arrays followed by annealing at 450°C for 2 h. The electrodeposition of BiOI film was carried out at different times (10, 30, 100, 500 and 1000 s) in Bi(NO3)3 and KI solution. The morphological, crystallographic and photoelectrochemical properties of the prepared BiVO4/TiO2/Ti heterojunction film were examined by using different characterization techniques. UV–vis spectrum absorption studies confirmed an increase in absorption intensities with increasing electrodeposition time, and the band gap of BiVO4/TiO2/Ti film is lower than that of TiO2/Ti. The photocatalytic efficiency of BiVO4/TiO2/Ti heterojunction film was higher compared to that of the TiO2/Ti film owing to the longer transient decay time for BiVO4/TiO2/Ti film (3.2 s) than that of TiO2/Ti film (0.95 s) in our experiment. The BiVO4/TiO2/Ti heterojunction film prepared by electrodeposition for 1000 s followed by annealing showed a high photocurrent density of 0.3363 mA cm−2 at 0.6 V versus saturated calomel electrode. Furthermore, the lowest charge transfer resistance from electrochemical impedance spectroscopy was recorded for the BiVO4/TiO2/Ti film (1000 s) under irradiation.

Achieving absorption–transmission switchable devices is still a great challenge due to the complex competitions among absorption, reflection, and transmission. Here, we propose a nanolayered terahertz (THz) metasurface exhibiting switchable functionality from quad-band near-perfect absorption to strongly enhanced transmission. The switchable performances are attributed to the electrical tunability of graphene and insulator–metal transition in vanadium dioxide (VO2). When VO2 functions as a metal, the proposed metasurface performs as a quad-band perfect absorber. The four absorption peaks can be effectively adjusted by altering the related graphene Fermi energy levels. When VO2 is in an insulating state, the proposed device functions as a THz antireflection coating, which diminishes reflection and substantially enhances transmission. In addition, a theoretical interference model is employed to clarify the physical mechanisms behind the near-perfect absorber and antireflection coating. The obtained theoretical results significantly agree with the numerical simulations. Furthermore, owing to the rotationally symmetric patterns, the performances of both the quad-band perfect absorber and antireflection coating are rather insensitive to light polarization and angle of incidence. Hence, our results can facilitate the progress of nanoscale switchable metadevices in the THz regime. [ABSTRACT FROM AUTHOR]

Metamaterial absorbers (MMAs) offer a novel and flexible method to realize perfect absorption in specific frequencies, especially in the THz range. Despite the exotic abilities to manipulate light, most previously reported MMAs still suffer from limited bandwidth and tunability. Here we present a thermally switchable terahertz (THz) metasurface that exhibits ultra-broadband absorption and high-transmission characteristics at different ambient temperatures. Our simulations demonstrate that at room temperature the structure is highly transparent. When the ambient temperature reaches 358 K, the proposed design exhibits an ultra-broadband absorption from 0.398 to 1.356 THz with the absorptivity maintaining above 90% and the relative absorption bandwidth reaches up to 109.2%. The structure is demonstrated to be insensitive to the incident angle. Moreover, the bandwidth of such a structure can easily be expanded or reduced by cascading or removing the rings, providing high scalability in practical applications. Such a thermally switchable THz metasurface may have potential applications in various fields, such as optical switching, THz imaging, modulating and filtering. [ABSTRACT FROM AUTHOR]

The "1+X" certificate system is an important content of the Action Plan for Vocational Education Reform, and the construction of the new form integrated teaching materials for "1 + X" certificate training of industrial robot integrated application is one of the important contents of the teaching reform of the certificate. Aiming at the 21 post groups corresponding to the X-certificate level standard of industrial robot integrated application, 12 occupational work field situations and 39 work tasks are designed, and the 12 occupational work field situations are matched with the professional teaching standard situations. The new form integrated teaching materials are designed from four aspects: the main training materials, courseware, video resources and the course learning platform. The practical results show that the industrial robot integrated application certificate training can better extend the existing professional teaching content, better realize the integration of the "Class-post-certificate", allow students to obtain the required vocational abilities of the industrial robot integrated application post group smoothly, which improves students' self-confidence in employment. [ABSTRACT FROM AUTHOR]

Chiral resolution of binaphthylamine is often a toilful conundrum in the field of analytical chemistry and biomedicine. The work puts forward a selective, sensitive, and miniaturized analytical method based on molecularly imprinted polymers (MIPs) as adsorbent for miniaturized tip solid‐phase extraction (MTSPE) in the separation of binaphthylamine enantiomer. This method combines the advantages of MIPs (high selectivity), MTSPE (low consumption), and high‐performance liquid chromatography (HPLC, high sensitivity). A simple synthesis methodology of MIP (P2) was conducted through bulk polymerization with (S)‐(−)‐1,1′‐binaphthyl‐2,2′‐diamine (S‐DABN) as template together with methacrylic acid monomer, and ethylene glycol dimethacrylate as cross‐linker in proper porogen, realizing a selective recognition and efficient enrichment for S‐DABN. The method exhibited appreciable linearity (0.06–1.00 mg ml−1), low quantification limit (0.056 mg ml−1), good absolute recoveries (45.70%–69.29%), and high precision (relative standard deviations ≤ 3.54%), along with low consumption (0.50 ml sample solution and 25.0 mg adsorbent). Based on the density functional theory, computational simulation was used to make a preliminary prediction for rational design of MIPs and gave a reasonable elaboration involving the potential mechanism of templates interacting with functional monomers. The adsorption kinetics and thermodynamics were investigated to evaluate the recombination process of substrates. In addition, the selectivity of MIPs for S‐DABN was obtained by MIP‐MTSPE coupled with HPLC, which supports the feasibility of this convenient design process. The proposed method was employed for selective extraction of S‐DABN and exhibited promising potential in the application of chiral analysis. [ABSTRACT FROM AUTHOR]