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

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 (similar to 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.

Automated summary

Indoor formaldehyde pollution is a serious threat to human health, but this study developed a g-C3N4-modified TiO2 composite photocatalyst that can degrade formaldehyde released from particle boards in real-time under visible light irradiation. The g-C3N4/TiO2 coating has a lower band gap energy, enabling it to effectively capture luminous energy in the visible light region. The photocatalytic coating exhibited high efficiency in degrading formaldehyde and maintained catalytic stability in various conditions. Hydroxyl and superoxide radicals were found to be the major active species responsible for formaldehyde degradation. This study provides a practical approach for improving indoor air quality through photocatalyst surface engineering.