Tio2@Hkust-1 Visible Light Photocatalyst for Degradation of Malodor: From Material Development to Air Purifier Application

Abstract

The combination of TiO2 with metal organic frameworks materials with good gas adsorption properties effectively solve its limitation on poor gas adsorption performance and low separation efficiency of photogenerated carriers in the purification of malodorous VOCs. In this paper, TiO2@HKUST-1 composites were successfully prepared by hydrothermal method. The adsorption-photocatalytic activity of the composites were investigated through degradation experiments on methyl mercaptan. Of all the composites, 0.1TiO2@HKUST-1 exhibits the highest photocatalytic activity, removing over 99% methyl mercaptan within 30 min. Additionally, it maintained stable performance throughout 20 cycles of photocatalytic experiments. A series of characterizations systemically demonstrate that the excellent photocatalytic performance resulted from a heterojunction constructed between TiO2 and HKUST-1. This structure provides a new pathway for the migration of photogenerated electrons, effectively enhancing the separation efficiency. Furthermore, a new type of air purifier has been investigated to purify indoor malodor. Compared to commercial air purifier using activated carbon filter cartridge as an absorbent to remove pollution, the new air purifier using TiO2@HKUST-1 as photocatalyst improved CH3SH degradation rate from 10% to 99% within 40 min under LED light. This study provides a new idea for the preparation of adsorption-photocatalytic functional materials and the efficient removal of methyl mercaptan.

Keywords: TiO2, HKUST-1, CH3SH, photocatalysis, adsorption