Attachment of facile synthesized NaCo2O4 nanodots to SiO2 nanoflakes for sodium-rich boosted Pt-dominated ambient HCHO oxidation

Fang Liu; Shiying Zhang; Long Wan; Yunjie Hao; Jiao Li; Hongqiang Wang; Zhongfu Li; Qiaoling Li; Chao Cao

doi:10.1016/j.jhazmat.2023.131969

Attachment of facile synthesized NaCo₂O₄ nanodots to SiO₂ nanoflakes for sodium-rich boosted Pt-dominated ambient HCHO oxidation

J Hazard Mater. 2023 Sep 15:458:131969. doi: 10.1016/j.jhazmat.2023.131969. Epub 2023 Jun 29.

Authors

Fang Liu¹, Shiying Zhang², Long Wan³, Yunjie Hao⁴, Jiao Li⁴, Hongqiang Wang⁴, Zhongfu Li⁵, Qiaoling Li⁴, Chao Cao⁶

Affiliations

¹ School of Materials Science and Engineering, Shandong University of Technology, Zibo 255000, PR China. Electronic address: liufangv@foxmail.com.
² Hunan Key Laboratory of Applied Environmental Photocatalysis, Changsha University, Changsha 410022, PR China. Electronic address: cszhangsy@ccsu.edu.cn.
³ College of Materials Science and Engineering, Hunan University, Changsha 410082, PR China.
⁴ School of Materials Science and Engineering, Shandong University of Technology, Zibo 255000, PR China.
⁵ School of Materials Science and Engineering, Shandong University of Technology, Zibo 255000, PR China; Shandong Collegial Engineering Research Center of Novel Rare Earth Catalysis Materials (CREC), Zibo 255000 Shandong, PR China.
⁶ Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, PR China.

PMID: 37399727
DOI: 10.1016/j.jhazmat.2023.131969

Abstract

Surface alkali metal ions are typically utilized as available promoters for ambient HCHO oxidation. In this study, NaCo₂O₄ nanodots with two different preferential crystallographic orientations are synthesized by facile attachment to SiO₂ nanoflakes with varying degrees of lattice defects. A unique Na-rich environment is established through interlayer Na⁺ diffusion based on the small size effect. The optimized catalyst Pt/HNaCo₂O₄/T₂ can deal with HCHO below 5 ppm in the static measurement system with a sustained release background and produces approximately 40 ppm of CO₂ in 2 h. Combining the experimental analyses with density functional theory (DFT) calculations, the possible catalytic enhancing mechanism is proposed from the support promotion perspective, and the positive synergistic effect of Na-rich, oxygen vacancies and optimized facets for Pt-dominant ambient HCHO oxidation via both kinetic and thermodynamic processes is confirmed.

Keywords: Ambient condition; Formaldehyde oxidation; Sodium cobalt oxide nanodots; Sodium-rich; Synergistic effects.