Real-Time Degradation of Indoor Formaldehyde Released from Actual Particle Board by Heterostructured g-C3N4/TiO2 Photocatalysts under Visible Light

Abstract

Indoor formaldehyde pollution causes a serious threat to human health since it is uninterruptedly released from wooden furniture. Herein, we prepared a g-C3N4-modified TiO2 composite photocatalyst and coated it on the surface of a commercial artificial particle board with the assistance of melamine formaldehyde adhesive. The g-C3N4/ TiO2 coating was then used to degrade formaldehyde which was released in real-time from the particle board under the irradiation of visible light. The results showed that compared with pure TiO2, the g-C3N4/ TiO2 composite with a heterojunction structure had a lower band gap energy (~2.6 eV), which could effectively capture luminous energy from the visible light region. Under continuous irradiation, the g-C3N4/ TiO2 photocatalytic coating was capable of degrading more than 50% of formaldehyde constantly released from the particle board. In the meantime, the photocatalytic coating also exhibited promising catalytic stability towards various formaldehyde release speeds, air flow velocities and environmental humidities. The hydroxyl radical and superoxide radical were found to be the predominant active species which triggered formaldehyde degradation. This study provides a feasible and practical approach for the improvement in indoor air quality through photocatalyst surface engineering.