Influence of the sol-gel preparation method on the photocatalytic NO oxidation performance of TiO2/Al2O3 binary oxides

Download
2015-03-01
Polat, Meryem
Soylu, Asli M.
Altunöz Erdoğan, Deniz
Erguven, Huseyin
Vovk, Evgeny I.
Ozensoy, Emrah
In the current work, TiO2/Al2O3 binary oxide photocatalysts were synthesized via two different sol-gel protocols (P1 and P2), where various TiO2 to Al2O3 mole ratios (0.5 and 1.0) and calcination temperatures (150-1000 degrees C) were utilized in the synthesis. Structural characterization of the synthesized binary oxide photocatalysts was also performed via BET surface area analysis, X-ray diffraction (XRD) and Raman spectroscopy. The photocatalytic NO(g) oxidation performances of these binary oxides were measured under UVA irradiation in a comparative fashion to that of a Degussa P25 industrial benchmark. TiO2/Al2O3 binary oxide photocatalysts demonstrate a novel approach which is essentially a fusion of NSR (NOx storage reduction) and PCO (photocatalytic oxidation) technologies. In this approach, rather than attempting to perform complete NOx reduction, NO(g) is oxidized on a photocatalyst surface and stored in the solidstate. Current results suggest that alumina domains can be utilized as active NOx capturing sites that can significantly eliminate the release of toxic NO2(g) into the atmosphere. Using either (P1) or (P2) protocols, structurally different binary oxide systems can be synthesized enabling much superior photocatalytic total NOx removal (i.e. up to 176% higher) than Degussa P25. Furthermore, such binary oxides can also simultaneously decrease the toxic NO2(g) emission to the atmosphere by 75% with respect to that of Degussa P25. There is a complex interplay between calcination temperature, crystal structure, composition and specific surface area, which dictate the ultimate photocatalytic activity in a coordinative manner. Two structurally different photocatalysts prepared via different preparation protocols reveal comparably high photocatalytic activities implying that the active sites responsible for the photocatalytic NO(g) oxidation and storage have a non-trivial nature.
CATALYSIS TODAY

Suggestions

EFFECT OF ION ASSOCIATION ON THE PROPERTIES OF IONOMERS OBTAINED FROM METHYL-METHACRYLATE METHACRYLIC-ACID COPOLYMER
KOCAK, HI; ARAS, L (Elsevier BV, 1990-07-01)
The solution behaviour of Na, Ba, Zn and Al ionomers of methyl methacrylate-methacrylic acid copolymer (P(MMA-MAA)) with different ion contents has been studied by viscosity and dipole moment measurements. Two solvents with different character are chosen for viscosity measurements: dioxane (ε = 2.22) and acetone (ε = 20.7). The expected polyelectrolyte behaviour of the ionomers in acetone is reflected by the viscometric measurements. Mean squared dipole moment 〈μ2〉 values are calculated over a temperature r...
DIPOLE-MOMENTS OF ISOTACTIC AND ATACTIC POLY(PROPYLENE OXIDE) SAMPLES
KUCUKYAVUZ, Z; ALYURUK, K; AHMAD, AM (Elsevier BV, 1991-01-01)
Dipole moments of poly(propylene oxide) (PPO) samples with different tacticities were determined from dielectric constant and refractive index increment measurements, which were performed on dilute toluene and isooctane solutions. In contrast to previous reports, both refractive index increments and the dipole moment ratios showed a marked dependence on the tacticities of the samples. The dipole moment ratios of isotactic samples were greater than unity and decreased with increasing sequence concentration...
Effects of synthesis, doping methods and metal content on thermoluminescence glow curves of lithium tetraborate
Kayhan, Mehmet; Yılmaz, Ayşen (Elsevier BV, 2011-07-28)
Lithium tetraborate: Li(2)B(4)O(7), (LTB) has been synthesized and doped with various Mn content by different methods, such as, high temperature solid state synthesis and solution assisted synthesis methods. Powder XRD results proved the formation of solid-solution by replacing Mn with Li ions in LTB lattice at lower amount of Mn doping, for example 0.1-3.0% Mn doping. In this research TL glow curves of Mn doped lithium tetraborate (LTB: Mn) produced by using different synthesis and doping methods and the e...
Influence of hydrogen bonding on electrochromic properties of conducting polymers
Akpinar, Hava; Nurioglu, Ayda Goycek; Toppare, Levent Kamil (2012-09-01)
4,7-Bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2-phenyl-1H-benzo[d]imidazole (BImBEd) was synthesized via Stille coupling reaction of 4,7-dibromo-2-phenyl-1H-benzo[d]imidazole (BImB) with monostannylated 3,4-ethylenedioxythiophene (EDOT). In order to figure out the presence of an intramolecular hydrogen bonding between the amine bond of the imidazole ring and the oxygen of the EDOT molecule, different amounts of trifluoroacetic acid (TFA) and concentrated sodium hydroxide (NaOH) solutions were added duri...
Influence of FEP nanoparticles in catalyst layer on water management and performance of PEM fuel cell with high Pt loading
Avcioglu, Gokce S.; FIÇICILAR, BERKER; Eroğlu, İnci (2017-01-05)
In this study, fluorinated ethylene propylene (FEP) nanoparticles were added to catalyst layer (CL) to facilitate excess water removal from the triple phase boundary in high Pt loading (1.2 mg/cm(2)) proton exchange membrane fuel cell (PEMFC) electrodes. The loading of PEP in the catalyst ink was varied from zero to 30 weight percentage. High-performance electrodes for anode and cathode were prepared by ultrasonic spray coating technique with a commercial catalyst containing 70 wt. % Pt on carbon. Different...
Citation Formats
M. Polat, A. M. Soylu, D. Altunöz Erdoğan, H. Erguven, E. I. Vovk, and E. Ozensoy, “Influence of the sol-gel preparation method on the photocatalytic NO oxidation performance of TiO2/Al2O3 binary oxides,” CATALYSIS TODAY, pp. 25–32, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46423.