We show why and how the spin state of transition-metal ions affects the thermoelectric properties of transition-metal oxides by investigating two perovskite-related oxides. In the A-site ordered cobalt oxide Sr3YCo4O10.5, partial substitution of Ca for Sr acts as chemical pressure, which compresses the unit cell volume to drive the spin state crossover, and concomitantly changes the magnetizati...

Q. Q. Lan,1,2 X. J. Zhang,1,3 X. Shen,1 H. W. Yang,1 H. R. Zhang,1,3 X. X. Guan,1,3 W. Wang,1,3 Y. Yao,1 Y. G. Wang,1 Y. Peng,2 B. G. Liu,1,3,* J. R. Sun,1,3,* and R. C. Yu1,3,* 1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China 2Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanz...

The structure-activity relations in the alumina-supported cobalt catalysts are studied at the realistic conditions of Fischer-Tropsch synthesis using in situ time-resolved XRD and catalytic measurements. Cobalt sintering during the first 3-5 h of the reaction and cobalt carbidisation at a longer time on stream (>8 h) coincide with catalyst deactivation.

We report how the thermopower of complex transition-metal oxides is susceptible to small changes in material parameters. In the A-site ordered perovskite oxide R(2/3)Cu(3)Ti(3.6)Ru(0.4)O(12), the thermopower changes from 15 to -100 microV K(-1) at 300 K in going from R = La to Er. We associate this with the hybridization between Cu 3d and Ru 4d electrons, which depends on R. For stronger hybrid...

First principles calculations using density functional theory with corrections for on-site Coulomb interactions (DFT + U) are presented in which we compute the energy for the conversion of CO to CO(2), NO(2) to NO and NO to N(2) over ceria surfaces. The surface sensitivity is discussed on the basis of the vacancy formation energies.

Abstract Aim The study was undertaken to determine the effect of amendments used in remediation cobalt-contaminated soil on macroelement content all organs spring barley (the main crop) and white mustard after-crop). Methods In experiment, six blocks were selected: without amendments; with manure (bovine, granulated); clay; charcoal; zeolite; calcium oxide (50%). each blocks, increasing doses c...

We report the synthesis of cerium oxide, cobalt oxide, mixed cerium, and cobalt oxides and a Ce-Co/Al₂O₃ membrane, which are employed as catalysts for the catalytic wet oxidation (CWO) reaction process and the removal of formaldehyde from industrial effluents. Formaldehyde is present in numerous waste streams from the chemical industry in a concentration low enough to make its recovery not econ...

Reactions of neutral cobalt oxide clusters (Co(m)O(n), m = 3-9, n = 3-13) with CO, NO, C(2)H(2), and C(2)H(4) in a fast flow reactor are investigated by time of flight mass spectrometry employing 118 nm (10.5 eV) single photon ionization. Strong cluster size dependent behavior is observed for all the oxidation reactions; the Co(3)O(4) cluster has the highest reactivity for reactions with CO and...