A TiO2/C catalyst having biomimetic channels and extremely low Pt loading for formaldehyde oxidation.

Wei Liu,Zi-Sheng Chao,Yutao Gong,Congmin Liu,Cai-Wu Luo,Xueping Li

doi:10.1039/c8ra10314c

Abstract

This study presents a TiO2/C hybrid material with biomimetic channels fabricated using a wood template. Repeated impregnations of pretreated wood chips in a Ti precursor were conducted, followed by calcination at 400–600 °C for 4 hours under a nitrogen atmosphere. The generated TiO2 nanocrystals were homogenously distributed inside a porous carbon framework. With an extremely low Pt catalyst loading (0.04–0.1 wt%), the obtained porous catalyst could effectively oxidize formaldehyde to CO2 and H2O even under room temperature (conv. ∼100%). Wood acted as both a structural template and reduction agent for Pt catalyst generation in sintering. Therefore, no post H2 reduction treatment for catalyst activation was required. The hierarchal channel structures, including 2–10 nm mesopores and 20 μm diameter channels, could be controlled by calcination temperature and atmosphere, which was confirmed by SEM and BET characterizations. Based on the abundant availability of wood templates and reduced cost for low Pt loading, this preparation method shows great potential for large-scale applications.

Highlights

This study presents a TiO2/C hybrid material with biomimetic channels fabricated using a wood template
Wood templated TiO2/C exhibited a hybrid structure; this resulted in the generation of TiO2 nanocrystals, which were homogenously distributed inside the porous carbon framework because the Ti precursor penetrated into wood tissues before catalyst sintering
The morphology of biomimetic channel-containing TiO2/C material prepared by the wood template is shown in Fig. 2, showing multi-scaled hierarchal structures

Summary

Introduction

This study presents a TiO2/C hybrid material with biomimetic channels fabricated using a wood template. The morphology of biomimetic channel-containing TiO2/C material prepared by the wood template is shown, showing multi-scaled hierarchal structures. The XRD characterization showed a high content ratio of anatase phase in the TiO2 samples prepared using the sol–gel method (shown in ESI, Fig. S2.†).

Results

Conclusion