Electrospun ceramic nanofibers can be ideal supports for catalyst, but commonly restricted by the rapid grain growth during fabrication and thus lose their superior functions. In this work, we reported grain growth suppressed nanofibers made of a blend of TiO₂ and Al₂O₃ with an average crystal size of 22.2 nm and 47.1 wt% of anatase on 900 °C. Al₂O₃ preferred to locate at the grain boundaries of TiO₂ nanograins, significantly hindering the coalescence among the neighboring TiO₂ nanograins. More intriguingly, Al₂O₃ spontaneously migrated to the surface and thus naturally formed a particle-on-fiber morphology. When serving as support, Al₂O₃/TiO₂ nanofibers offered promoted adhesion for Pt nanoparticles, by taking advantages of the well-preserved grain boundaries and anatase phase. Moreover, the dual-oxide construction built kinetic bottleneck to prevent Pt nanoparticles from moving across the support to attach to or merge with each other. Therefore, Pt nanoparticles can be stabilized against sintering up to 500 °C with an ultra-close neighboring distance of 4.56 nm. This sinter-resistant catalyst exhibited high activities toward both liquid-phase hydrogenation and gas-phase oxidation reactions (i.e. soot oxidation) at high temperatures. Such a robust and thermally stable catalyst can be further used for catalytic soot oxidation, giving great prospects for emission control.

电纺陶瓷纳米纤维可以用作催化剂的理想载体，但通常在制造过程中会受到晶粒快速生长的限制，从而失去其优越的功能。在这项工作中，我们报道了由TiO ₂和Al ₂ O ₃的混合物制成的晶粒生长抑制纳米纤维，其平均晶体尺寸为22.2 nm，在900°C时的锐钛矿含量为47.1 wt％。Al ₂ O ₃优选位于TiO ₂纳米颗粒的晶界处，这显着阻碍了相邻的TiO ₂纳米颗粒之间的聚结。更有趣的是Al ₂ O ₃自发迁移到表面，因此自然形成了纤维上的颗粒形态。当用作载体时，Al ₂ O ₃ / TiO ₂纳米纤维通过利用保存完好的晶界和锐钛矿相，提高了对Pt纳米颗粒的附着力。而且，双氧化物结构建立了动力学瓶颈，以防止Pt纳米粒子穿过载体移动以彼此附着或融合。因此，可以稳定Pt纳米颗粒，使其在4.56 nm的超近邻距离下烧结至500°C。这种耐烧结催化剂在高温下对液相氢化和气相氧化反应（即烟灰氧化）均显示出高活性。这种坚固且热稳定的催化剂可进一步用于催化烟灰氧化，为排放控制提供了广阔的前景。