Core-Sheath CeO2/SiO2 Nanofibers as Nanoreactors for Stabilizing Sinter-Resistant Pt, Enhanced Catalytic Oxidation and Water Remediation

One-dimensional (1D) oxide nanofibers have attracted much attention in recent years but are still hampered by the difficulty in the expansion to 2D or 3D dimensions. Herein, ultrathin CeO2/SiO2 nanofibers with intriguing core-sheath structures were simply fabricated by a facile single-spinneret electrospinning method and were subsequently integrated as 2D nanofibrous mats and 3D sponges. Introducing secondary oxide (i.e., SiO2) could induce a unique fine structure and further inhibit the sintering of CeO2 nanocrystals, endowing the resultant dual-oxide nanofibers with high porosity, good flexibility, and enriched oxygen defects. Benefiting from the core-sheath structure and dual-oxide component, the CeO2/SiO2 nanofibers could stabilize 2.59 nm-Pt clusters against sintering at 600 degrees C. Once assembled into a 2D mat, the nanofibers could efficiently decrease the soot oxidation temperature by 63 degrees C. Moreover, the core-sheath CeO2/SiO2 nanofibers can be readily integrated with graphene nanosheets into a 3D sponge via a gas foaming protocol, showing 218.5 mg/g of adsorption capacity toward Rhodamine B molecules. This work shed lights on the versatile applications of oxide nanofibers toward clean energy ultilization and low-carbon development.