Development of a metal-free black phosphorus/graphitic carbon nitride heterostructure for visible-light-driven degradation of indomethacin

• Published in: The Science of the total environment Vol. 804; p. 150062
• Main Authors: He, Dongyang, Jin, Dexin, Cheng, Fangyuan, Zhang, Tingting, Qu, Jiao, Zhou, Yangjian, Yuan, Xing, Zhang, Ya-nan, Peijnenburg, Willie J.G.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.01.2022
• Subjects: Black phosphorus; carbon nitride; environment; graphene; Graphitic carbon nitride; indomethacin; light; lighting; Pharmaceuticals and personal care products; phosphorus; Photocatalysis; photocatalysts; reactive oxygen species; remediation; sewage effluent; sewage treatment; solar radiation; surface water; tap water; water treatment; Pharmaceuticals and personal care products; Photocatalysis; Black phosphorus; Graphitic carbon nitride
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2021.150062

The development of affordable and efficient technologies for the removal of pharmaceuticals and personal care products (PPCPs) from water has recently been the subject of extensive attention. In this study, a black phosphorus/graphitic carbon nitride (BP-g-C3N4) heterostructure is fabricated as an extremely active metal-free photocatalyst via a newly-developed exfoliation strategy. The BP-g-C3N4 shows an 11 times better decomposition rate of a representative PPCPs-type pollutant, indomethacin (IDM), compared to the widely-used P25 TiO2 under real-sunlight illumination. Also, its visible-light activity is even better than that of the best photocatalysts previously developed, but only consumes 1/10–1/4 of the catalyst. The results show that BP performs a cocatalyst-like behavior to catalyze the generation of reactive oxygen species, thus speeding up the decomposition of IDM. In addition, the BP-g-C3N4 photocatalyst also exhibits excellent IDM removal efficiency in authentic water matrices (tap water, surface water, and secondarily treated sewage effluent). Large-scale application demonstration under natural sunlight further reveals the practicality of BP-g-C3N4 for real-world water treatment operations. Our work will open up new possibilities in the development of purely metal-free photocatalysts for “green” environmental remediation applications. [Display omitted] •A low-cost BP-g-C3N4 photocatalyst is fabricated via a newly-developed strategy.•The BP-g-C3N4 significantly outperforms the P25 TiO2 under natural sunlight.•Mechanism for the enhanced photocatalytic activity is proposed.•Effect of natural water constituents and water matrices is studied.