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A Pt/rGO/PDA@ITO composite of Pt nanoparticles (NPs), reduced graphene oxide (rGO) and polydopamine (PDA) has been obtained on indium tin oxide glass (ITO). Firstly, a rGO/PDA@ITO composite of rGO and PDA on ITO was formed by immersing ITO into a dopamine solution at room temperature and then a graphene oxide (GO) suspension solution in a water bath at 60 °C for 3 h. Ag NPs were then deposited on the rGO/PDA@ITO surface by immersing rGO/PDA@ITO in an AgNO3 aqueous solution with the aid of ascorbic acid. Finally, Pt/rGO/PDA@ITO was obtained by immersing Ag/rGO/PDA@ITO in a platinum tetrachloride solution in the presence of ascorbic acid. Localized surface plasmon resonance (LSPR) of the Pt NPs has been found at 260 nm from UV-visible spectra. Cyclic voltammetry curves of Pt/rGO/PDA@ITO and UV absorption peaks of the Pt NPs implied that the sample with the strongest LSPR is the optimal electrocatalyst for methanol oxidation. Cyclic voltammetry of Pt/rGO/PDA@ITO showed that the ratio of current intensity between the forward scan and reverse scan peaks (If/Ib) was 1.768, indicating the remarkable anti-poison property of Pt/rGO/PDA@ITO as an electrocatalyst. Its electrochemical active surface area can reach 2.60 m2 g−1 at a scan rate of 50 mV s−1. It was found that the current decreased only 38.7% after 200 cycles. The better stability also confirmed the superior tolerance of carbon monoxide and catalytic activity. [ABSTRACT FROM AUTHOR]

Herein, on a zinc substrate, a superhydrophobic Co5Zn21 alloy surface with a nanometer needle structure was fabricated by immersing processed Zn sheets perpendicularly into a cobalt(ii) nitrate aqueous solution followed by the annealing treatment. This alloy surface exhibited not only outstanding superhydrophobicity with a water contact angle of 160° but also excellent mechanical durability and corrosion resistance. The morphology and chemical composition of the superhydrophobic surface (SHS) were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction pattern (XRD), energy-dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The corrosion resistance of the samples was characterized via polarization, Nyquist, and bode modulus plots. The SHS endures mechanical stretch for more than 800 mm of abrasion using sandpaper with different grit sizes (P1200, P800, and P400) and shows abrasion resistance. When the superhydrophobic surface lost its superhydrophobicity after a long-term damage, the superhydrophobicity could be easily regenerated again by immersion and annealing treatment. The surface after repair can still maintain its superhydrophobicity after anti-friction, anti-ice, and UV irradiation tests. [ABSTRACT FROM AUTHOR]

In this work, a facile approach was developed for producing stable Ag–Fe2O3/Fe superhydrophobic surfaces (SHSs) with dendritic structures. The hierarchical structures were fabricated on iron substrates through etching in a hydrochloric acid aqueous solution and a simple replacement deposition process was carried out without any organic modification, followed by annealing. The contact angle can reach 164 ± 1° and the sliding angle is almost 2 ± 1°. By comparison, the catalytic properties of the hydrophilic sample and SHS were examined. The SHS exhibited excellent catalytic performance. The rate constant of SHS was 3.00 × 10−3 s−1, which was about three times higher than that of the hydrophilic sample without annealing, and the degradation rate was maintained above 90% after ten recycles. The experimental results showed that the as-prepared SHSs exhibited excellent catalytic, self-cleaning, anti-corrosion, and anti-icing properties. [ABSTRACT FROM AUTHOR]

Stable bulk glasses from the quaternary system Cu–As–Te–Se are investigated for thermoelectric applications. These materials exhibit a low thermal conductivity κ∼ 0.3 W K−1 m−1 which is appealing for raising the thermoelectric figure of merit ZT. The addition of small amounts of selenium within the telluride amorphous matrix plays two fundamental roles. First, the increased disorder associated with the size mismatch improves glass-formation and widens the glass-formation domain, and second, it increases phonon scattering and slightly decreases the thermal conductivity. Furthermore, the addition of copper up to 32% dramatically increases the electrical conductivity without notably affecting the thermal conductivity. This permits us to obtain bulk glass samples with promising thermoelectric properties, which could be manufactured through conventional low-cost glass casting methods. While addition of copper permits the increase of electrical conductivity by more than six orders of magnitude, another three orders of magnitude are required to obtain thermoelectric materials with competitive ZT. Nevertheless, predicted values of ZT ＞ 1.2 are estimated which would constitute some of the highest reported figure of merit for a bulk solid at room temperature. The effect of glass annealing on thermoelectric properties is also discussed. [ABSTRACT FROM AUTHOR]