Scalable perovskite–ceria nanointerfaces with oxide–oxide charge transfer for robust CO oxidation

: Perovskite catalysts exhibit excellent thermal stability but suffer from insufficient activity, creating an activity–stability trade-off that hinders their practical implementation. Constructing interfaces with reducible oxides (e.g., LaCoO 3 /CeO 2 ) can overcome this limitation via electronic metal oxide-support interaction (eMOSI), yet controllable synthesis remains challenging. Here, we report a “solid–liquid–solid” nanoparticle-transfer method for the scalable fabrication of supported LaCoO 3 /CeO 2 heterostructures, in which LaCoO 3 crystallization is completed before its deposition onto CeO 2 . Preformed LaCoO 3 nanoparticles are transferred from a removable NaCl matrix onto CeO 2 , thereby bypassing support-mediated co-nucleation and the differential migration of La and Co species. Remarkably, the 5 wt.% LaCoO 3 /CeO 2 -SLS catalyst achieves a LaCoO 3 -mass-normalized CO consumption rate of 1.16×10 −4 mol·g LaCoO3 −1 ·s −1 , nearly two orders of magnitude higher than that of pristine LaCoO 3 at 160 °C. It also exhibits exceptional durability (near-500 h on stream) and can be scaled to kilogram scale without performance loss. XRD, Raman, EELS, Ce L 3 -edge XANES, and DFT calculations collectively reveal interfacial electron transfer from LaCoO 3 toward CeO 2 with partial ceria reduction, thereby promoting CO oxidation. This work provides a general powder-processing strategy for constructing supported multicomponent oxide interfaces and demonstrates the potential of interfacial electronic engineering for scalable catalytic powder manufacturing.