B-Site-Controlled Redox and Activity of Lattice Oxygen of LaBO ₃ Perovskite Nanoparticles for Chemical Looping Oxidative Dehydrogenation

Perovskite oxides (ABO3) are promising oxygen carrier materials for chemical looping processes due to their structural flexibility and redox cyclability. To guide the rational design of high-performance carriers, a fundamental understanding of how the B-site cation governs the lattice oxygen reactivity is essential. In this work, a series of LaBO3 (B = Fe, Co, Ni, Cr, Mn) perovskite nanoparticles were designed and synthesized via a sol–gel method for chemical looping oxidative dehydrogenation (CL-ODH) of ethane. A comprehensive investigation combining multiscale characterization and density functional theory (DFT) calculations was conducted to establish structure–performance relationships. The results reveal that the identity of the B-site element critically determines the electronic structure (O p-band center position and B 3d–O 2p hybridization), which, in turn, modulates the metal–oxygen bond strength and the energy barrier for oxygen release. Consequently, a distinct catalytic performance emerges: LaNiO3 (1.97 eV) and LaCoO3 (2.36 eV), with low oxygen desorption energies, facilitate deep oxidation to CO2, while LaMnO3 (2.47 eV), possessing a moderate oxygen desorption energy and structural stability, achieves the highest ethylene selectivity (31.6%) and yield (21.3%) at 750 °C by suppressing overoxidation. This study reveals the key role of B-site cations in regulating the redox properties of perovskite materials, providing strategic insights and a theoretical foundation for the design of advanced oxygen carrier materials with tailored activity and selectivity for chemical looping technologies.