Flame‐Made Pt‐Loaded TiO₂ Thin Films and Their Application as H₂ Gas Sensors

Abstract

The hydrogen gas sensors were developed successfully using flame-made platinum-loaded titanium dioxide (Pt-loaded TiO2) nanoparticles as the sensing materials. Pt-loaded TiO2thin films were prepared by spin-coating technique onto Al2O3substrates interdigitated with Au electrodes. Structural and gas-sensing characteristics were examined by using scanning electron microscopy (SEM) and showed surface morphology of the deposited film. X-ray diffraction (XRD) patterns can be confirmed to be the anatase and rutile phases of TiO2. High-resolution transmission electron microscopy (HRTEM) showed that Pt nanoparticles deposited on larger TiO2nanoparticles. TiO2films loaded with Pt nanoparticles were used as conductometric sensors for the detection of H2. The gas sensing of H2was studied at the operating temperatures of 300, 350, and 400°C in dry air. It was found that 2.00 mol% Pt-loaded TiO2sensing films showed higher response towards H2gas than the unloaded film. In addition, the responses of Pt-loaded TiO2films at all operating temperatures were higher than that of unloaded TiO2film. The response increased and the response time decreased with increasing of H2concentrations.

A Real-Time Detection Algorithm of Flame Target Image

“…It is known from experience that the scintillation rate of flame is about 8 Hz [33][34][35][36]. erefore, we used the continuous pixel value changes of each frame in the video to extract the flicker characteristic information of the flame center.…”

A Review of the Single-Step Flame Synthesis of Defective and Heterostructured TiO2 Nanoparticles for Photocatalytic Applications

“…In most cases, platinum acetylacetonate (C 10 H 14 O 4 Pt) and platinum chloride hexahydrate (H 2 PtCl 6 •6H 2 O) were used as the Pt metal precursor mixed with TTIP or TBT. The Pt precursor and Ti precursor were premixed as a binary metal feeding solution and sprayed into a single flame [99,[126][127][128][129]. In some cases, the Pt precursors were fed separately by a sublimation unit into the same flame [130].…”

“…The FS enabled the loading of Pt metal at an ultralow concentration as well as well-dispersed single-atom Pt onto the surface of the TiO 2 , which was mainly attributed to this extremely high H 2 evolution reaction. Moreover, the FS-made Pt/TiO 2 can potentially be utilized for various catalytic reactions, such as the mineralization of organic matters [127,129], catalytic hydrogenation of 3-nitrostyrene [126], SO 2 oxidation [130] and gas sensors [128]. Pd loading: Fujiwara et al synthesized Pd single-atom-, sub-nanocluster-and nanoparticle-supported TiO2 composites from a solution precursor of 2-ethylhexanoic acid, acetonitrile, TTIP and palladium acetylacetonate in a CH4/O2 flame [101,102,122].…”

TiO2 Gas Sensors Combining Experimental and DFT Calculations: A Review

“…However, the results of Abdelilah Lahmar et al [ 67 ] showed that the size of platinum particles was independent of the annealing atmosphere and the properties of precursors. Additionally, Weerasak Chomkitichai et al [ 68 ] allowed loading on by preparing hydrogen sensors through spin-coating -loaded films on substrates using the flame-made method. Thanks to the spillover effect, the operating temperature was reduced to when of was loaded, at which time, the hydrogen concentration was and the response value was 470, and thus, the spillover effect was maximized.…”