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A fast and facile pulse combustion (PC) method that allows for the continuous production of multigram quantities of high-metal-loaded and highly uniform supported metallic nanoparticles (SMNPs) is presented. Namely, various metal on carbon (M/C) composites have been prepared by using only three feedstock components: water, metal–salt, and the supporting material. The present approach can be elegantly utilized also for numerous other applications in electrocatalysis, heterogeneous catalysis, and sensors. In this study, the PC-prepared M/C composites were used as metal precursors for the Pt NPs deposition using double passivation with the galvanic displacement method (DP method). Lastly, by using thin-film rotating disc electrode (TF-RDE) and gas-diffusion electrode (GDE) methodologies, we show that the synergistic effects of combining PC technology with the DP method enable production of superior intermetallic Pt–M electrocatalysts with an improved oxygen reduction reaction (ORR) performance when compared to a commercial Pt–Co electrocatalyst for proton exchange membrane fuel cells (PEMFCs) application.

During the last decade the focus in superconductivity research has shifted towards the manufacturing of easy-to-handle superconductors, because of their high usability in electronic applications in comparison to bulky ceramics. This article reviews our recent progress made in the buffer-layer architecture of such a coated conductor, focusing on CeO 2 thin films prepared by an aqueous sol-gel method and deposited by dip-coating. Starting from water-soluble cerium(III) nitrate precursors, we were able to deposit films showing a very high degree of [002] orientation depending on the film characteristics and synthesis conditions. The formation and stability of the chemical complexes in the solu-

When working with chemical solution deposition techniques, one of the main issues for optimal performance of CeO2 buffer layers in coated conductors is the insufficient chemical stability of the CeO2 layer during YBa2Cu3O7 (YBCO) thermal processing. This work focusses on the morphology and nanostructure in thin CeO2 films prepared by means of a novel aqueous synthesis route and incorporated into a Ni–W/La2Zr2O7/CeO2/YBa2Cu3O7‐coated conductor. Optimization of precursor chemistry and thermal processing led to a reduction in barium cerate formation. In a new precursor design, iminodiacetic acid was used as a stabilizing ligand, which resulted in an improved morphology of the buffer layer. A shelf life of more than 6 months was established by using a metal‐to‐ligand ratio of 1 to 5. During thermal processing, a combination of a slow calcination ramp with a high sintering ramp, short sintering dwell time and a low oxygen partial pressure during the synthesis resulted in a root mean square roughness below 3 nm for AFM analysis, a [111] to [002] ratio of 1 to 90 in X‐ray diffraction and well‐defined patterns in reflection high‐energy electron diffraction (RHEED) analysis of the CeO2 surface. Trifluoroacetate‐YBCO was deposited on top of the CeO2 buffer layer. Cross‐section analysis with a focussed ion beam allowed us to correlate the morphology and nanostructure of the CeO2 buffer layer with the formation of BaCeO3 and the appearance of voids and secondary phases throughout the YBa2Cu3O7 layer.

A novel water based precursor solution using ethylenediaminetetraacetic acid (H4EDTA) as a complexant and acetic acid and ethylenediamine (EDA) as additional components to obtain CeO2 buffer layers on Ni (5%W) tapes is described in detail. The influence of complexation behavior in the formation of transparent and homogenous sols and gels by the combination of cerium acetate, acetic acid and H4EDTA has been studied. The optimal growth conditions for cerium oxide were Ar-5% H2 gas processing atmosphere, solution concentration levels of 0.2–0.4 M, a dwell time of 60 min at 900 °C and 5–30 min at 1,050 °C. X-ray diffraction, SEM, spectroscopic ellipsometry and pole figures were used to characterize the CeO2 films. Highly textured CeO2 layers were obtained

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Studies of the production of fiber-forming polyamide 6 (PA6)/graphene composite material and melt-spun textile fibers are scarce, but research to date reveals that achieving the high dispersion state of graphene is the main challenge to nanocomposite production. Considering the significant progress made in the industrial mass production of graphene nanoplatelets (GnPs), this study explored the feasibility of production of PA6/GnPs composite fibers using the commercially available few-layer GnPs. To this aim, the GnPs were pre-dispersed in molten ε-caprolactam at concentrations equal to 1 and 2 wt %, and incorporated into the PA6 matrix by the in situ water-catalyzed ring-opening polymerization of ε-caprolactam, which was followed by melt spinning. The results showed that the incorporated GnPs did not markedly influence the melting temperature of PA6 but affected the crystallization temperature, fiber bulk structure, crystallinity, and mechanical properties. Furthermore, GnPs increased the PA6 complex viscosity, which resulted in the need to adjust the parameters of melt spinning to enable continuous filament production. Although the incorporation of GnPs did not provide a reinforcing effect of PA6 fibers and reduced fiber tensile properties, the thermal stability of the PA6 fiber increased. The increased melt viscosity and graphene anti-dripping properties postponed melt dripping in the vertical flame spread test, which consequently prolonged burning within the samples.