MoO3 Nanorods Coated with MoS2 Nanosheets for Photocatalytic Elimination of Bacteria and Formaldehyde

The development of a green and environmentally friendly photocatalytic multifunctional coating in the field of architectural coatings is crucial. To this end, a simple hydrothermal method was constructed for the growth of MoS2 in situ on modified MoO3, and a photocatalytic coating with full-spectrum elimination of bacterial and formaldehyde, using a waste bioresource of eggshells as a substrate and MoO3@MoS2 as the photocatalyst. The prepared photocatalytic coating has an excellent antibacterial effect on Gram-positive bacteria represented by S. aureus and Gram-negative bacteria represented by E. coli and also has significant effectiveness in the elimination of formaldehyde. MoO3@MoS2 generates electron–hole pairs, and the formation of S-heterojunctions demonstrated by in situ XPS under full-spectrum xenon lamp (0.28 W/cm2) irradiation increases the photogenerated electron–hole pair separation and improves the photocatalytic performance of the coating. Combining the photothermal effect and the increased specific surface area of discarded eggshells to enhance adsorption properties, the coating showed almost 99.9% antimicrobial resistance against S. aureus and E. coli within 10 min. At the same time, the elimination rate for high concentrations of formaldehyde is also about 92.5% with 30 min. This photocatalytic coating offers a promising strategy for the secondary use of waste bioresources and green coatings.