Browsing by Subject "Perovskite"

Article

Catalytic behavior of La-Sr-Ce-Fe-O mixed oxidic/perovskitic systems for the NO+CO and NO+CH4+O2 (lean-NOx) reactions

Belessi, Vassiliki C.; Costa, Costas N.; Bakas, Thomas V.; Anastasiadou, T.; Pomonis, Phillippos J.; Efstathiou, Angelos M. (2000)

Mixed oxides of the general formula La0.5SrxCeyFeOz were prepared by using the nitrate method and characterized by XRD and Mossbauer techniques. The crystal phases detected were perovskites LaFeO3 and SrFeO3-x and oxides ...

Article

Comparative study of La-Sr-Fe-O perovskite-type oxides prepared by ceramic and surfactant methods over the CH4 and H2 lean-deNOx

Stathopoulos, Vassilis N.; Belessi, Vassiliki C.; Bakas, Thomas V.; Neophytides, Stylianos G.; Costa, Costas N.; Pomonis, Phillippos J.; Efstathiou, Angelos M. (2009)

Mixed oxides of the general formula La0.8Sr0.2FeO3-x were prepared by ceramic and surfactant methods and tested towards the NO/H2/O2 and NO/CH4/O2 lean-deNOx reactions in the 200-450 °C range. The materials were characterized ...

Article

Comparative study of the magnetic and magnetotransport properties of a metallic and a semiconducting member of the solid solution LaNixCo1-xO3

Androulakis, J.; Katsarakis, N.; Viskadourakis, Z.; Giapintzakis, John (2003)

A metallic and a semiconducting member of the solid solution LaNixCo1-xO3 (x=0.2, 0.6) with their magnetic and magnetotransport properties was investigated. The members of the perovskite solid solution were found on opposite ...

Article

Hall effect study of magnetoresistive perovskite LaNi0.5Co 0.5O3 thin films

Androulakis, J.; Giapintzakis, John (2004)

We report on the Hall effect of LaNi0.5Co0.5O 3 magnetoresistive thin films grown on Si(100) substrates by pulsed laser deposition. The Hall resistivity exhibits sign reversals both in varying magnetic field and temperature, ...

Article

LaSrMnCoO6: A new cubic double perovskite oxide

Androulakis, J.; Katsarakis, N.; Giapintzakis, John; Vouroutzis, N.; Pavlidou, E.; Chrissafis, K.; Polychroniadis, E. K.; Perdikatsis, V. (2003)

Single-phase polycrystalline powder samples of the double perovskite oxide LaSrMnCoO6 were synthesized by the Pechini (citrate-gel) technique. The structural, magnetic and electrical properties of the obtained powders were ...

Article

Lead halide perovskites and other metal halide complexes as inorganic capping ligands for colloidal nanocrystals

Dirin, D. N.; Dreyfuss, S.; Bodnarchuk, M. I.; Nedelcu, G.; Papagiorgis, Panagiotis; Itskos, Grigorios; Kovalenko, M. V. (2014)

Lead halide perovskites (CH3NH3PbX3, where X = I, Br) and other metal halide complexes (MXn, where M = Pb, Cd, In, Zn, Fe, Bi, Sb) have been studied as inorganic capping ligands for colloidal nanocrystals. We present the ...

Article

Long-Lived Hot Carriers in Formamidinium Lead Iodide Nanocrystals

Papagiorgis, Panagiotis; Protesescu, L.; Kovalenko, M. V.; Othonos, Andreas S.; Itskos, Grigorios (2017)

The efficient harvesting of hot carrier energy in semiconductors is typically inhibited by their ultrafast thermalization process. Recently, highly promising experiments reported on the slowdown of the intraband relaxation ...

Article

Magnetoresistance in LaNi1-xCoxO3 (0.3≤x≤0.6)

Androulakis, J.; Giapintzakis, John (2010)

We report on a detailed study of the electrical resistivity and the magnetoresistance of the metallic members of the LaNi1-xCoxO3 series with 0.3≤x≤0.6. The low-temperature resistivity of the compounds with 0.3≤x≤0.5 ...

Article

Realization of La2MnVO6: Search for half-metallic antiferromagnetism?

Androulakis, J.; Katsarakis, N.; Giapintzakis, John (2002)

Single-phase polycrystalline La2MnVO6 samples were synthesized by arc-melting and characterized by X-ray diffraction, magnetization and resistivity measurements. We find that the compound has cubic (space group Fm3̄m), ...

Article

Surface reactivity of LaCoO3 and Ru/LaCoO3 towards CO, CO2 and C3H8: Effect of H2 and O2 pretreatments

Álvarez-Galván, M. C.; Constantinou, D. A.; Navarro, R. M.; Villoria, J. A.; Fierro, José Luis García; Efstathiou, Angelos M. (2011)

The differences in surface reactivity of LaCoO3 and Ru/LaCoO3 solids after pre-treatment in a hydrogen or oxygen gas atmosphere towards oxidative steam reforming (OSR) of propane was probed by performing temperature-programmed ...

Article

Synergistic effects of crystal phases and mixed valences in La-Sr-Ce-Fe-O mixed oxidic/perovskitic solids on their catalytic activity for the NO+CO reaction

Belessi, Vassiliki C.; Bakas, Thomas V.; Costa, Costas N.; Efstathiou, Angelos M.; Pomonis, Phillippos J. (2000)

Mixed oxidic and perovskite-type materials based on the La, Sr, Ce and Fe elements were prepared using a mixture of nitrates salts and heating at 1000°C. Three groups of solids were synthesized: (i) La(1-y)Ce(y)FeO3 (y=0.2, ...