Structure–activity relationship of an A-site-doped LaNiO₃/SiO₂ catalyst

Abstract

Improving the anti-carbon deposition and anti-sintering ability under the premise of maintaining high catalytic activity is the core issue of Ni-based catalysts applied in CO methanation reactions. To address this issue, a La0.75A0.25NiO3/SiO2 (A = Ce, Sr, Sm, and Ca) catalyst is prepared via a citric acid complexation method. XRD results show that the substituted elements (Sr, Sm, and Ca) enter the LaNiO3 lattice and partially replace the A-site element La. The reduced Ni0 is beneficial to improve the medium temperature activity of the catalyst. The substitution of different elements produces different electronic effects that significantly affect the size of the Ni particles and the interaction between Ni and La2O3. The catalyst with doped Ca2+ as the A-site substituted element demonstrates better adsorption, storage, and migration capabilities for oxygen due to the lattice distortion that easily produces oxygen vacancies. Catalysts doped with Sr, Sm, and Ca as the A-site substituted element produce La2O2CO3 after the reactions, which plays a role in eliminating carbon deposits.

Perovskite‐based electrocatalyst discovery and design using word embeddings from retrained SciBERT language model

“…LaNiO 3 is another bifunctional electrocatalyst material capable of catalyzing OER and ORR reactions 54,55 . It has also found use in CO methanation reaction 43 . The presence of Nickel makes it a candidate for such applications.…”

“…54,55 It has also found use in CO methanation reaction. 43 The presence of Nickel makes it a candidate for such applications. Nickel-based perovskites also exhibit good conductivity, which adds to their characteristics to be considered as a candidate electrocatalyst material.…”