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Perovskite oxides (ABO3) due to their high thermal stability and the ability to control the physico-chemical properties are considered as an alternative to traditional catalysts containing noble and transition metals. Herein, the recent research breakthroughs of GdCoO3 catalysts in experimental studies are summarized in detail. First, the perovskite-type GdCoO3 complex oxides were obtained by co-precipitation method with the various precipitators and were characterized by X-ray diffraction (XRD), low temperature nitrogen adsorption and IR spectroscopy. Physical and chemical analysis showed that the choice of precipitant doesn’t significantly affect the phase composition of the perovskites. The catalytic performance of gadolinium cobaltites was discussed. It was found that the use of cobaltites obtained by co-precipitation leads to the inhibition of the side reaction of the reverse steam reforming of carbon monoxide. Finally, the investigation of the used catalysts demonstrated the formation of Gd2O2CO3 and metallic cobalt, which indicates the nature of active centres: gadolinium is the centre of CO adsorption, while hydrogen chemisorption occurs on cobalt-sites.

The effect of strontium substitution in the structure of the complex oxide Gd2SrFe2O7 on the production of light olefins by CO hydrogenation was investigated. Perovskite-type oxides Gd2−xSr1+xFe2O7 (x = 0; 0.1; 0.2; 0.3; 0.4) were synthesized by sol–gel technology and characterized by XRD, Mössbauer spectroscopy, BET specific area, acidity testing, and SEM. The experimental data revealed a correlation between the state of iron atoms, acidity, and catalytic performance. It was found that with an increase in the content of Sr2+ in the perovskite phase, the basicity of the surface and the oxygen diffusion rate increased. This contributed to the CO dissociative adsorption, formation of active carbon, and its further interaction with atomic hydrogen. [ABSTRACT FROM AUTHOR]

The influence of Yb3+ cations substitution for Pr3+ on the structure and catalytic activity of (Pr1−xYbx)2Zr2O7 powders synthesized via coprecipitation followed by calcination is studied using a combination of long- (s-XRD), medium- (Raman, FT-IR, and SEM-EDS) and short-range (XAFS) sensitive methods, as well as adsorption and catalytic techniques. It is established that chemical composition and calcination temperature are the two major factors that govern the phase composition, crystallographic, and local-structure parameters of these polycrystalline materials. The crystallographic and local-structure parameters of (Pr1−xYbx)2Zr2O7 samples prepared at 1400 °C/3 h demonstrate a tight correlation with their catalytic activity towards propane cracking. The progressive replacement of Pr3+ with Yb3+ cations gives rise to an increase in the catalytic activity. A mechanism of the catalytic cracking of propane is proposed, which considers the geometrical match between the metal–oxygen (Pr–O, Yb–O, and Zr–O) bond lengths within the active sites and the size of adsorbed propane molecule to be the decisive factor governing the reaction route. [ABSTRACT FROM AUTHOR]

Perovskite oxides (ABO3) due to their high thermal stability and the ability to control the physico-chemical properties are considered as an alternative to traditional catalysts containing noble and transition metals. Herein, the recent research breakthroughs of GdCoO3 catalysts in experimental studies are summarized in detail. First, the perovskite-type GdCoO3 complex oxides were obtained by co-precipitation method with the various precipitators and were characterized by X-ray diffraction (XRD), low temperature nitrogen adsorption and IR spectroscopy. Physical and chemical analysis showed that the choice of precipitant doesn't significantly affect the phase composition of the perovskites. The catalytic performance of gadolinium cobaltites was discussed. It was found that the use of cobaltites obtained by co-precipitation leads to the inhibition of the side reaction of the reverse steam reforming of carbon monoxide. Finally, the investigation of the used catalysts demonstrated the formation of Gd2O2CO3 and metallic cobalt, which indicates the nature of active centres: gadolinium is the centre of CO adsorption, while hydrogen chemisorption occurs on cobalt-sites. [ABSTRACT FROM AUTHOR]