Surface oxygen vacancies promoted Pt nanoparticles on celery-like CeO2 nanofibers for enhanced sinter-resistance and catalytic performance

Supported metal nanoparticles hold great promise for heterogeneous catalysis but are greatly persecuted by the poor thermal stability upon high temperatures. In this work, we facilely synthesized intriguing celery-like CeO2 nanofibers with high surface areas and hierarchical pores and channels by single-spinneret electrospinning. The nanofibers were explored as reliable support for polyvinylpyrrolidone (PVP)-stabilized Pt nanoparticles, followed by activation at 350 degrees C in N-2 to eliminate PVP stabilizer and generate sufficient surface oxygen vacancies. Therefore, the resultant Pt@CeO2 was endowed with enhanced metal-support interaction and thereby promoted sinter-resistance. In this case, the Pt@CeO2 exhibited over six times higher activity after aging at 600 degrees C toward the hydrogenation of p-nitrophenol than that of Pt-PVP/CeO2. Moreover, the thermal-stable Pt@CeO2 significantly decreased the activation energy of soot oxidation from 178.0 kJ/mol to 109.4 kJ/mol, due to the abundant oxygen vacancies, as well as the promoted solid-solid contact by the interconnected and celery-like CeO2 nanofibers. After such a sinter-promoting exothermic reaction, the supported Pt nanoparticles maintained a small size of 5.78 nm. This approach provides a facile method to prepare noble metal catalysts with both high atom economy and sinterresistance. (C) 2022 Elsevier Ltd. All rights reserved.

Automated summary

In this study, celery-like CeO2 nanofibers were synthesized and used as a reliable support for Pt nanoparticles to enhance their catalytic activity and sinter resistance. The Pt@CeO2 nanoparticles showed stable catalytic performance at high temperatures.