The Role of Strontium in CeNiO3 Nano-Crystalline Perovskites for Greenhouse Gas Mitigation to Produce Syngas

The transition metal-based catalysts for the elimination of greenhouse gases via methane reforming using carbon dioxide are directly or indirectly associated with their distinguishing characteristics such as well-dispersed metal nanoparticles, a higher number of reducible species, suitable metal-support interaction, and high specific surface area. This work presents the insight into catalytic performance as well as catalyst stability of CexSr1-xNiO3 (x = 0.6-1) nanocrystalline perovskites for the production of hydrogen via methane reforming using carbon dioxide. Strontium incorporation enhances specific surface area, the number of reducible species, and nickel dispersion. The catalytic performance results show that CeNiO3 demonstrated higher initial CH4 (54.3%) and CO2 (64.8%) conversions, which dropped down to 13.1 and 19.2% (CH4 conversions) and 26.3 and 32.5% (CO2 conversions) for Ce0.8Sr0.2NiO3 and Ce0.6Sr0.4NiO3, respectively. This drop in catalytic conversions post strontium addition is concomitant with strontium carbonate covering nickel active sites. Moreover, from the durability results, it is obvious that CeNiO3 exhibited deactivation, whereas no deactivation was observed for Ce0.8Sr0.2NiO3 and Ce0.6Sr0.4NiO3. Carbon deposition during the reaction is mainly responsible for catalyst deactivation, and this is further established by characterizing spent catalysts.

Automated summary

This study investigates the catalytic performance and stability of CexSr1-xNiO3 nanocrystalline perovskite catalysts for hydrogen production via methane reforming using carbon dioxide. It is found that strontium incorporation enhances the specific surface area, number of reducible species, and nickel dispersion. The catalytic performance results show that the addition of strontium decreases the conversion rates due to the coverage of nickel active sites by strontium carbonate. The durability results indicate that CeNiO3 exhibits deactivation, while Ce0.8Sr0.2NiO3 and Ce0.6Sr0.4NiO3 do not show deactivation.