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

Perovskite oxides (ABO 3 ) 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 LaBO 3 (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: LaNiO 3 (1.97 eV) and LaCoO 3 (2.36 eV), with low oxygen desorption energies, facilitate deep oxidation to CO 2, while LaMnO 3 (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.