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.

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In this paper we study several temperature sensing techniques using the same thermographic phosphor: luminescence intensity ratio, lifetime, rise time. Moreover, we analyze some recently presented techniques, based on host luminescence intensity ratio method and delayed gate intensity ratio technique. We have selected YVO 4 :Eu 3+ nano powder as an appropriate material for this study, because it has easily detectable luminescence rise time and host luminescence. The material was prepared using simple solution combustion synthesis. The time resolved analysis of emission spectra was achieved using the streak camera system. We present a very detailed analysis of measured lifetimes and rise times of all emission lines and their temperature dependence. We propose a multimode temperature sensing technique based on the concept of luminescence detection part of the temperature sensor capable of switching between several measurements modes to obtain the best sensitivity in desired range of operation.

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e gadolinium vanadate doped with samarium (GdVO 4 :Sm 3+ ) nanopowder was prepared by the solution combustion synthesis (SCS) method. After synthesis, in order to achieve the full crystallinity, the material was annealed in air atmosphere at 900°C. Phase identification in the postannealed powder samples was performed by X-ray diffraction, and morphology was investigated by high-resolution scanning electron microscopy (SEM). Photoluminescence characterization of the emission spectrum and timeresolved analysis have been performed using the tunable laser optical parametric oscillator excitation and the streak camera. Several strong emission bands in the Sm 3+ emission spectrum were observed, located at 567 nm ( 4 G 5/2 -6 H 5/2 ), 604 nm ( 4 G 5/2 -6 H 7/2 ), and 646 (654) nm ( 4 G 5/2 -6 H 9/2 ), respectively. e weak emission bands at 533 nm ( 4 F 3/2 -6 H 5/2 ) and 706 nm ( 4 G 5/2 -6 H 11/2 ) and a weak broad luminescence emission band of VO 4 3− were also observed by the detection system. We analyzed the possibility of using the host luminescence for two-color temperature sensing. e proposed method is improved by introducing the temporal dependence in the line intensity ratio measurements.