Effect of ytterbium doping on the microstructure and plastic deformation of BaCeO3 perovskite oxide

Effects of noble metals doped on mesoporous LaAlNi mixed oxide catalyst and identification of carbon deposit for reforming CH4 with CO2

“…The conversion of CH 4 and CO 2 over Ru/Spinel catalyst was 73.08% and 75.38%, and the yield of H 2 and CO was 71.93% and 74.23%, respectively, with an H 2 /CO molar ratio of 0.969. Many studies have been carried out that aimed to synthesize mixed‐oxides with perovskite‐type structure suitable for CH 4 conversion, such as steam reforming, partial oxidation of methane and dry reforming. Perovskites are highly stable under the severe conditions imposed by these reactions, such as high temperature .…”

Profound Understanding of Effect of Transition Metal Dopant, Sintering Temperature, and pO2 on the Electrical and Optical Properties of Proton Conducting BaCe0.9Sm0.1O3−δ

“…Observation of BaCO 3 suggests the interaction of the basic sites of BaCeO 3 with atmospheric CO 2 . The variation in the lattice parameters upon introducing a TM in BCS is shown in Table and compared with BaCe 0.9 Y 0.1 O 3 and BaCeO 3 . − The small ionic size of a TM ions is expected to cause contraction of the perovskite lattice, while the oxide ion vacancy tends to expand the lattice . However, TMs might also have a negligible solubility in BCS, segregate at the grain-boundaries and work as sintering aids, as reported in fluorite structure. , Considering the lattice volume to evaluate the effect of each dopant on the unit cell of BCS, the bigger ionic size of Sm 3+ in 6-fold coordination (0.96 Å) was expected to expand the lattice of BCS upon replacing Ce 4+ (0.87 Å) .…”

“…Table shows that there is no certain trend in the estimated cell volume regarding the TM-doped BCS based on their ionic radius. This could be due to (i) a deficiency in the Ba content that was manifested as BaCO 3 formation; (ii) existence of a small percent of unreacted Sm 2 O 3 in Fe- and Co-doped samples; and (iii) incorporation of Sm in A-site to maintain the perovskite structure upon depletion in Ba that might occur during the mixing process in solution. ,, Based on atomistic study, Haile et al, pointed out that the Ba deficiency in the A-site will drive certain acceptor-dopants to occupy A-site, and it can be expressed as where Ba Ba x and Sm Ba • represent Ba 2+ at the Ba 2+ site and Sm 3+ at the Ba 2+ site, respectively. This was reported only for the dopants that exhibit ionic radius comparable to Ba 2+ in 12-coordination, such as La 3+ and Sm 3+ .…”

“…This could be due to (i) a deficiency in the Ba content that was manifested as BaCO 3 formation; (ii) existence of a small percent of unreacted Sm 2 O 3 in Fe-and Co-doped samples; and (iii) incorporation of Sm in A-site to maintain the perovskite structure upon depletion in Ba that might occur during the mixing process in solution. 16,17,24 Based on atomistic study, Haile et al, 25 pointed out that the Ba deficiency in the A-site will drive certain acceptor-dopants to occupy A-site, and it can be expressed as…”