Raman spectroscopy characterization of molybdena supported on titania-zirconia mixed oxide

Miciukiewicz, J.; Mang, Th.; Knözinger, Helmut

doi:10.1016/0926-860x(94)00236-3

Cited by 66 publications

(27 citation statements)

References 17 publications

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“…There are sharp bands at 1350-1380 cm À1 accompanied by four broad but split bands at 1213-1215, 1110-1121, 1059-1073 and 995-1010 cm À1 , indicating the presence of two kinds of sulfated species. The bands at 1350-1380 cm À1 corresponds to the asymmetric S@O stretching frequency of sulfate ion bonded to TiO 2 -ZrO 2 under the dehydrated condition, while the latter four bands are assigned to bidentate sulfate ion coordinated to TiO 2 -ZrO 2 [9,22,23]. These results are very similar to those of other workers [23,25].…”

Section: Resultssupporting

confidence: 92%

“…However, the frequency shift of this band is different depending on the evacuation temperature, as shown in figure 1. At 25°C an asymmetric stretching band of S@O bonds was not observed because the water molecules are adsorbed on the surface of 20-NiSO 4 /TiO 2 -ZrO 2 [9,22,23]. The bands at 1630 cm À1 are due to the H 2 O absorbed on the surface.…”

Section: Resultsmentioning

confidence: 67%

“…This is probably due to the fact that the adsorbed water reduces the bond order of S@O from a highly covalent double-bond character to a lesser double-bond character. The strong ability of the sulfur complex to accommodate electron from a basic molecule such as H 2 O is a driving force in generating superacidic properties [9,22,23].…”

Section: Resultsmentioning

confidence: 99%

“…The TiO 2 -ZrO 2 binary oxide has also been reported to exhibit high surface acidity by a charge imbalance based on the generation of Ti-O-Zr bonding [18]. Further, recent studies also reveal that TiO 2 -ZrO 2 is an active catalyst for dehydrocyclization of n-paraffins to aromatics [19], hydrogenation of carboxylic acids to alcohols [20] and photo catalytic oxidation of acetone [21], and also is an effective support for MoO 3 -based catalysts for hydroprocessing application [22]. Thus, the mixed TiO 2 -ZrO 2 oxide has attracted attention recently as a catalyst and support for various applications.…”

Section: Introductionmentioning

confidence: 97%

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Correlation between acidic properties of nickel sulfate supported on TiO2-ZrO2 and catalytic activity for ethylene dimerization

2005

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A series of catalysts, NiSO 4 /TiO 2 -ZrO 2 , for ethylene dimerization was prepared by the impregnation method using an aqueous solution of nickel sulfate. For NiSO 4 /TiO 2 -ZrO 2 sample, no diffraction line of nickel sulfate was observed up to 30 wt%, indicating good dispersion of nickel sulfate on the surface of TiO 2 -ZrO 2 . The addition of nickel sulfate to TiO 2 -ZrO 2 shifted the phase transition of TiZrO 4 from amorphous to orthorhombic to a higher temperature because of the interaction between nickel sulfate and TiO 2 -ZrO 2 . The number of acid sites of NiSO 4 /TiO 2 -ZrO 2 increased in proportion to the nickel sulfate content up to 20 wt% of NiSO 4 . Nickel sulfate supported on TiO 2 -ZrO 2 was found to be very active even at room temperature, giving a maximum in both activity and acidity, when the catalyst containing 20% NiSO 4 was calcined and evacuated at 500°C. The asymmetric stretching frequency of the S @ O bonds for NiSO 4 /TiO 2 -ZrO 2 samples was related to the acidic properties and catalytic activity. That is, the higher the frequency, the higher both the number of acid sites and the catalytic activity for ethylene dimerization.

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Section: Resultssupporting

confidence: 92%

Section: Resultsmentioning

confidence: 67%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 97%

See 2 more Smart Citations

Correlation between acidic properties of nickel sulfate supported on TiO2-ZrO2 and catalytic activity for ethylene dimerization

2005

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show abstract

“…The TiO 2 -ZrO 2 binary oxide has also been reported to exhibit high surface acidity by a charge imbalance based on the generation of Ti-O-Zr bonding [15]. Further, recent studies also reveal that TiO 2 -ZrO 2 is an active catalyst for dehydrocyclization of n-paraffins to aromatics [16], hydrogenation of carboxylic acids to alcohols [17] and photo catalytic oxidation of acetone [18], and also is an effective support for MoO 3 -based catalysts for hydroprocessing application [19] and for NiSO 4 catalyst for ethylene dimerization [20] and acid catalysis [5]. Thus, the mixed TiO 2 -ZrO 2 oxide has attracted attention recently as a catalyst and as a support for various applications.…”

Section: Introductionmentioning

confidence: 97%

Characterization of Supported NiSO4 and Effect of TiO2–ZrO2 Composition on Catalytic Activity for Acid Catalysis

Sohn

Lee

2007

Catal Lett

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A series of catalysts, NiSO 4 /TiO 2 -ZrO 2 having different TiO 2 -ZrO 2 composition, for acid catalysis was prepared by the impregnation method using an aqueous solution of nickel sulfate. The addition of TiO 2 to ZrO 2 improved the surface area of the catalyst and enhanced its acidity remarkably because of the formation of new acid sites through the charge imbalance of Ti-O-Zr bonding. The binary oxide, TiO 2 -ZrO 2 calcined above 600°C resulted in the formation of crystalline orthorhombic phase of ZrTiO 4 . Therefore, NiSO 4 /TiO 2 -ZrO 2 calcined at 500°C exhibited a maximum catalytic activity for acid catalysis, and then the catalytic activity decreased with the calcination temperature. The correlation between catalytic activity and acidity held for both reaction, 2-propanol dehydration and cumene dealkylation. NiSO 4 supported on 50TiO 2 -50ZrO 2 (TiO 2 /ZrO 2 ratio = 1) among TiO 2 -ZrO 2 binary oxides exhibited the highest catalytic activity for acid catalysis.

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Degenerately Hydrogen Doped Molybdenum Oxide Nanodisks for Ultrasensitive Plasmonic Biosensing

Zhang

Zavabeti

Chrimes

et al. 2018

Adv Funct Materials

112

105

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Plasmonic biosensors based on noble metals generally suffer from low sensitivities if the perturbation of refractive‐index in the ambient is not significant. By contrast, the features of degenerately doped semiconductors offer new dimensions for plasmonic biosensing, by allowing charge‐based detection. Here, this concept is demonstrated in plasmonic hydrogen doped molybdenum oxides (HxMoO3), with the morphology of 2D nanodisks, using a representative enzymatic glucose sensing model. Based on the ultrahigh capacity of the molybdenum oxide nanodisks for accommodating H+, the plasmon resonance wavelengths of HxMoO3 are shifted into visible‐near‐infrared wavelengths. These plasmonic features alter significantly as a function of the intercalated H+ concentration. The facile H+ deintercalation out of HxMoO3 provides an exceptional sensitivity and fast kinetics to charge perturbations during enzymatic oxidation. The optimum sensing response is found at H1.55MoO3, achieving a detection limit of 2 × 10−9m at 410 nm, even when the biosensing platform is adapted into a light‐emitting diode‐photodetector setup. The performance is superior in comparison to all previously reported plasmonic enzymatic glucose sensors, providing a great opportunity in developing high performance biosensors.

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Raman spectroscopy characterization of molybdena supported on titania-zirconia mixed oxide

Cited by 66 publications

References 17 publications

Correlation between acidic properties of nickel sulfate supported on TiO2-ZrO2 and catalytic activity for ethylene dimerization

Correlation between acidic properties of nickel sulfate supported on TiO2-ZrO2 and catalytic activity for ethylene dimerization

Characterization of Supported NiSO4 and Effect of TiO2–ZrO2 Composition on Catalytic Activity for Acid Catalysis

Degenerately Hydrogen Doped Molybdenum Oxide Nanodisks for Ultrasensitive Plasmonic Biosensing

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