Facile Construction of Bi2MoO6/Bi/g-C3N4 toward Efficient Photocatalytic Oxidation of Indoor Gaseous Formaldehyde with a Wide Concentration Range under Visible Light Irradiation

The removal of formaldehyde ( HCHO) has attracted tremendous attention, because the toxicity and volatility of HCHO seriously affect human health. It is urgent to develop a catalyst that can efficiently remove HCHO in indoor conditions. Here, the Bi2MoO6/Bi/g-C3N4 heterojunction is prepared by a simple hydrothermal approach and subsequently an in situ reduction. The prepared material is used to photocatalytic degrade HCHO from 50 to 1600 ppm under simulated indoor conditions, presenting 96.15% conversion for 200 ppm and 98.80% for 1600 ppm under 10 h of visible light irradiation. Its long-term utility was confirmed with an unchanged activity after six recycling tests at a long 60 h of visible light illumination. An environmental factor estimation indicates its superior CO2 selectivity (99.79%) and excellent humidity resistance. The good performances are assigned to the Bi nanoparticles produced in situ, linking Bi2MoO6 and g-C3N4 together, which contribute to the excellent visible light harvesting, quick separation of electron-hole pairs, strong adsorption toward HCHO, and less shedding and aggregation. The materials could also be utilized to effectively removal general gaseous pollutants (C6H6 and CH3COOCH2CH3). This work is expected to develop a novel material that could be potentially integrated into the instrument for remedying of indoor gas.