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With distinct ion insertion-induced tinting behavior, tungsten oxide (WO 3 ) has been intensively studied as a representative electrochromic (EC) material for many years. To enhance its EC properties, strategies including nanostructuring, plasmonic engineering, and metal ion doping have been adopted. Here, we show that rare earth element of gadolinium (Gd) doping can effectively improve the coloration efficiency ( η ) of a sputtered amorphous WO 3 (∼30% enhancement at the maximum of eye-sensitive wavelength of 520 nm for 0.57 wt% doping). By combining the film structural characterization and electrochemical analysis, such an increment can be attributed to the monoclinic Gd 2 O 3 nanoislands formed on WO 3 surface which enhanced charge capacity and reaction kinetics of the film. The large transmittance modulation (76% at 800 nm), high coloration efficiency (68.3 cm 2  C −1 at 633 nm) and fast switching speed (7.8 and 10.4 s for coloration and bleach time, respectively) were achieved for the modest Gd-doped WO 3 film (0.9%). However, further increasing of Gd doping results in decreasing of η , which could be attributed to the excess amount of Gd 2 O 3 that inhibits the penetration of electrolyte into the active material. We believe that the understanding of the Gd-doping effect on the electrochemical behaviours of WO 3 may shed light on selecting the proper doping elements and their concentration for energy-saving smart windows. [ABSTRACT FROM AUTHOR]

Nanostructured WO 3 films prepared by an industry compatible method with large surface area and strong adhesive force to the substrate are highly desired for electrochromic (EC) applications. Here, we report the preparation of a kind of WO 3 nanoisland films on indium-doped tin oxide (ITO)-coated glass substrates by Ag-induced reactive sputtering deposition combined with a post-etching treatment. Our study demonstrates that compared with the bare WO 3 film, the nanoisland film exhibits apparently enhanced EC performance, including high luminous transmittance (92.8%) in a bleached state, high luminous coloration efficiency (126.4 cm2/C), relatively fast color-switching time (7.1 s for coloring and 12.1 s for bleaching), decent long-term cycling stability (2000 cycles) and improved self-bleaching ability. Electrochemical kinetics analysis indicates that such enhanced EC performance relies on large lithium-ion diffusion coefficient (2.37 × 10−10 cm2/s), a good ability of charge storage (10.82 mF/cm2), and low charge-transfer resistance (196 Ω) of the nanoisland microstructure. The results shed light on exploring a novel method to prepare high EC performance WO 3 film. Image 1 • WO 3 nanoisland films can be fabricated by Ag-induced magnetron sputter deposition combined with a post-etching treatment, which significantly increases the contact interface between the electrolyte and materials. • The special nanostructure promotes the electrochromic performance eminently: higher optical transmittance (92.8%), coloration efficiency (126.4 cm2/C) and fast response time (7.1 s for coloring and 12.1 s for bleaching). • The electrochemical performance was analyzed to explain the internal cause relying on large ion diffusion coefficient (2.37 × 10−10 cm2/s), good charge storage (10.82 mF/cm2), and low charge-transfer resistance (196 Ω). [ABSTRACT FROM AUTHOR]

• We have prepared a series of Au@Ag NPs with size-controlled Ag shell thickness (1 nm, 3 nm, 5 nm, 7 nm and 9 nm Ag shells) as the SERS substrates. • We have developed a novel label-free and ultrasensitive SERS based detection method for native protein • Based on the concentration-dependent SERS spectra, CRC biomarker NDKA and homologous protein NDKD can be identified directly for the first time. Moreover, several label-free proteins were also detected at ultralow concentrations with good reproducibility and high sensitivity. Early detection is vital for the prevention and treatment of patients with colorectal cancer (CRC). However, existent methods (such as enzyme immunoassay, chemiluminescent immunoassay and radioimmunoassay) for early detection of CRC are time consuming, costly and complicated multistage processes, limiting their further applications. Here, a novel label-free and ultrasensitive detection method is developed for CRC protein marker NDKA by Cr3+ ions aggregating Au@Ag NPs (ICNPs) via surface-enhanced Raman spectroscopy (SERS) spectra for the first time. The Au@Ag NPs with size-controlled Ag shell thickness (1 nm, 3 nm, 5 nm, 7 nm and 9 nm Ag shells) are prepared as the SERS substrates and its Raman signals are Ag shells thickness-dependent sensitivity to proteins. By using Cr3+ ions as aggregating agents, the aggregating effect between the SERS substrates of Au@Ag ICNPs and protein analyte results in significantly enhanced and reproducible Raman signals owing to formation of lots of hotspots. Using this novel method, several label-free proteins, myoglobin (3 fg/mL), human serum albumin (30 fg/mL), lysozyme (30 ng/mL) and cytochrome C (30 ng/mL) were also detected at ultralow concentrations with good reproducibility and high sensitivity, demonstrating the potential applications in the fields of medical therapy and clinical diagnosis. [ABSTRACT FROM AUTHOR]

This study examines the microstructure of La 2 Mg 17 /Ni composites produced by ball-milling with lithium bromide, and the effect of varying this LiBr addition on the electrochemical properties of the resulting electrode material. Through this, it was found that LiBr helps prevent crystallization of the alloy, thereby refining the particle size and ensuring a uniform distribution of amorphous and nanocrystalline particles. This structure greatly improved the electrochemical properties of the composite, with the maximum discharge capacity increasing from 176.8 to 550.38 mA h/g. Further investigation of the electrochemical behaviour of the composite electrode revealed that the addition of 5 wt.% LiBr reduces the contact resistance, increases the electrochemical impedance, enhances the limiting current density and improves the charge/discharge equilibrium rate. [ABSTRACT FROM AUTHOR]

• TiO 2 film was deposited on surface of Ni50Ti50 substrate using atomic layer deposition techniques. • TiO 2 film thickness, surface roughness, corrosion resistance and biocompatibility were investigated. • TiO 2 film thickness is directly proportional with number of ALD cycles. • The maximum corrosion resistance, excellent surface morphology and Cell proliferation was achieved after 200 ALD cycles. NiTi shape memory alloys (SMAs) have been widely applied in biomedical fields due to their excellent shape memory effect, super-elasticity, and biocompatibility. In this study, the plasma- enhanced atomic layer deposition was applied to deposit TiO 2 film on the surface of Ni50Ti50 substrate. The characterization and surface properties of TiO 2 film, bending strain test, corrosion resistance, nickel release and in vitro biocompatibility were studied to evaluate the performance of ALD-TiO 2 film. The results show that the ALD-TiO 2 film is uniform and exhibits an amorphous structure. The ALD-TiO 2 films are less hydrophilic than the Ni50Ti50 substrate. As the deposition cycle increases, the water contact angle of ALD-TiO 2 film only changes slightly. The ALD-TiO 2 film exhibits an adequate adhesion to the Ni50Ti50 substrate and can withstand proper bending strain. ALD-TiO 2 film can effectively inhibit the release of nickel ions. After being immersed in the simulated body fluid for 30 days, the amount of nickel ions released decreases from 60 ppb for Ni50Ti50 substrate to 20–20 ppb for Ni50Ti50 with 200-cycle ALD-TiO 2 film. Meanwhile, Ni50Ti50 with ALD-TiO 2 films have better corrosion resistance than the Ni50Ti50 substrate. In vitro biocompatibility reveals that the ALD-TiO 2 film can enhance cell adhesion, promote cell proliferation and reduce cytotoxicity. After 5 days of culture, the 200-cycle ALD-TiO 2 film can enhance the cell proliferation by 2.7 times and reduce the cytotoxicity from 48% for Ni50Ti50 substrate to 37% for Ni50Ti50 with 200-cycle ALD-TiO 2 film. These results indicate that the TiO 2 films deposited by PE-ALD technique can effectively improve the biocompatibility of NiTi SMAs. [ABSTRACT FROM AUTHOR]

Abstract: MgF2 coating on BaMgAl10O17:Eu2+ (BAM) particles was obtained by an emulsion method. The chemical compositions, microstructure, and luminescent performance of surface-coating BAM were characterized by XRD, X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), energy dispersion spectrum (EDS) and vacuum ultraviolet (VUV) excitation, respectively. The results indicate that a compact homogeneous MgF2 film is successfully coated on the surface of BAM particles by forming a chemical bond. Lengthening of fluorescence lifetimes were observed in surface-coated BAM phosphor attributed to less non-radiative rate due to coating. The luminescent performances of surface-coated BAM is improved due to the hanging-bonds and defects on the surface of nano-scale BAM particles being removed as well as non-radiative transition probability decreasing. [Copyright &y& Elsevier]

Abstract: By adopting a feasible microwave-induced solution combustion synthesis (MISCS) method, pure and well-crystallized BaMgAl10O17:Eu2+ (BAM) nanoscale blue phosphors were successfully prepared. The crystallinity, particle size, morphology, chemical composition and luminescent properties were characterized by XRD, FE-SEM, EDS and spectrofluorometer, respectively. The results show that the obtained BAM phosphors have spherical morphology, good crystallinity, and strong blue emission under vacuum ultraviolet (VUV) light excitation compared to those prepared by conventional solution combustion method. [Copyright &y& Elsevier]