Kinetic studies on using photocatalytic coatings for removal of indoor volatile organic compounds

TL;DR

This study develops a model to evaluate the effectiveness of doped-TiO2 photocatalytic coatings in removing VOCs under real indoor conditions, addressing the gap between small-scale experiments and actual applications.

Contribution

The paper introduces a predictive model for photocatalytic VOC removal efficiency considering indoor conditions and coating design, advancing practical indoor air purification solutions.

Findings

Doped-TiO2 coatings effectively improve indoor air quality.

Indoor ambient conditions significantly influence photocatalytic performance.

Coating design impacts VOC removal efficiency.

Abstract

Titanium dioxide (TiO2) is a known photocatalyst with a capability of decomposing organic substance. However, the photocatalysis of the pure TiO2 is not effective for the indoor environment due to a lack of the ultraviolet irradiation inside the building. Doping TiO2 with substance such as C, N or metal can extend the threshold of the absorption spectrum to the visible spectrum region. Thus, doped-TiO2 is able to decompose volatile organic compounds (VOCs) under an indoor environment. To date, most experimental work reported on photocatalytic kinetics were conducted inside small-scale devices. The performance of air purification function under the actual indoor application scenery need to be further clarified. For this purpose, it is crucial to predict the performance of autogenous air quality improvements by visible light driven photocatalyst for the actual applications. This work has developed a model to evaluate the performance of functional coating with photocatalyst in removing VOCs. Factors such as the effects of coating designs and indoor ambient conditions on the air purification efficiency were studied. This work demonstrates that doped-TiO2 photocatalytic coating is effective to improve the indoor air quality.