FG Keramische Werkstoffe

5 Items

Recent Submissions
Surface chemistry and stability of metastable corundum-type In2O3

Köck, Eva-Maria ; Kogler, Michaela ; Zhuo, Chen ; Schlicker, Lukas ; Bekheet, Maged F. ; Doran, Andrew ; Gurlo, Aleksander ; Penner, Simon (2017)

To account for the explanation of an eventual sensing and catalytic behavior of rhombohedral In2O3 (rh-In2O3) and the dependence of the metastability of the latter on gas atmospheres, in situ electrochemical impedance spectroscopic (EIS), Fourier-transform infrared spectroscopic (FT-IR), in situ X-ray diffraction and in situ thermogravimetric analyses in inert (helium) and reactive gases (hydro...

Ultramicroporous silicon nitride ceramics for CO2 capture

Schitco, Cristina ; Seifollahi Bazarjani, Mahdi ; Riedel, Ralf ; Gurlo, Aleksander (2015)

Carbon dioxide (CO2) capture is regarded as one of the biggest challenges of the 21st century; therefore, intense research effort has been dedicated in the area of developing new materials for efficient CO2 capture. Here, we report high CO2 capture capacity in the low region of applied CO2 pressures observed with ultramicroporous silicon nitride-based material. The latter is synthesized by a fa...

A study on the thermal conversion of scheelite-type ABO(4) into perovskite-type AB(O,N)(3)

Li, Wenjie ; Li, Duan ; Gao, Xin ; Gurlo, Aleksander ; Zander, Stefan ; Jones, Philip ; Navrotsky, Alexandra ; Shen, Zhijian ; Riedel, Ralf ; Ionescu, Emanuel (2015)

Phase-pure scheelite AMoO(4) and AWO(4) (A = Ba, Sr, Ca) were thermally treated under an ammonia atmosphere at 400 to 900 degrees C. SrMoO4 and SrWO4 were shown to convert into cubic perovskite SrMoO2N and SrWO1.5N1.5, at 700 degrees C and 900 degrees C respectively, and to form metastable intermediate phases (scheelite SrMoO4-xNx and SrWO4-xNx), as revealed by X-ray diffraction (XRD), elementa...

The contrasting effect of the Ta/Nb ratio in (111)-layered B-site deficient hexagonal perovskite Ba5Nb4-xTaxO15 crystals on visible-light-induced photocatalytic water oxidation activity of their oxynitride derivatives

Hojamberdiev, Mirabbos ; Bekheet, Maged F. ; Zahedi, Ehsan ; Wagata, Hajime ; Vequizo, Junie Jhon M. ; Yamakata, Akira ; Yubuta, Kunio ; Gurlo, Aleksander ; Domen, Kazunari ; Teshima, Katsuya (2016)

The effect of the Ta/Nb ratio in the (111)-layered B-site deficient hexagonal perovskite Ba5Nb4-xTaxO15 (0 <= x <= 4) crystals grown by a KCl flux method on visible-light-induced photocatalytic water oxidation activity of their oxynitride derivatives BaNb1-xTaxO2N (0 <= x <= 1) was investigated. The Rietveld refinement of X-ray data revealed that all Ba5Nb4-xTaxO15 samples were well crystallize...

Enhanced catalytic performance of MnxOy-Na2WO4/SiO2 for the oxidative coupling of methane using an ordered mesoporous silica support

Yildiz, M. ; Aksu, Y. ; Simon, U. ; Kailasam, K. ; Görke, O. ; Rosowski, F. ; Schomäcker, R. ; Thomas, A. ; Arndt, S. (2014)

The oxidative coupling of methane is a highly promising reaction for its direct conversion. Silica supported MnxOy–Na2WO4 is a suitable catalyst for this reaction. In this study, a variety of different SiO2 materials have been tested as supports. Surprisingly, the application of ordered mesoporous silicas, here exemplarily shown for SBA-15 as support materials, greatly enhances the catalytic pe...