Hydroxylation and sodium intercalation on g-C3N4 for photocatalytic removal of gaseous formaldehyde. (30th April 2021)

• Record Type: Journal Article
• Authors: Hu, Chechia; Tsai, Wei-Fan; Wei, Wei-Han; Andrew Lin, Kun-Yi; Liu, Miao-Ting; Nakagawa, Keizo
• Is Part Of: Carbon. Volume 175(2021)
• Page Start: 467
• Page End: 477
• Publication Date: 2021-04-30
• Subjects: HCHO -- g-C3N4 -- Hydroxyl group -- Na intercalation -- Photocatalysis; Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2021.01.112
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: In this study, hydroxyl-modified/Na-intercalated g-C3 N4 was used as an effective material for the removal of gaseous formaldehyde (HCHO) through adsorption and photocatalytic oxidation. In a simple reflux reaction using different NaOH concentrations, the surface-grafted hydroxyl (‒OH) groups of g-C3 N4 formed internal hydrogen bonds with gaseous HCHO, while the Na atoms intercalated into the layered structure of g-C3 N4 to create an electron transfer path (layer‒Na‒layer) to improve charge separation for photocatalytic oxidation. The hydroxylation as well as Na intercalation of g-C3 N4 significantly increased its HCHO removal efficiency compared with that of bare g-C3 N4 . The HCHO removal capacity of the modified g-C3 N4 reached approximately 0.12 ppm g −1 min −1, which was twice that of bare g-C3 N4 (<0.06 ppm g −1 min −1 ). Moreover, the modified g-C3 N4 was reused at least thrice without any decline in activity. This work provides a facile, simple, and fast approach to the modification of g-C3 N4 via hydroxylation and Na intercalation to enhance HCHO adsorption as well as electron transfer, rendering it a promising material for indoor HCHO removal. Graphical abstract: Image 1 Highlights: Hydroxyl-modified and Na-intercalated g-C3 N4 was prepared via treatment with NaOH. Hydroxylation of g-C3 N4 significantly improved HCHO adsorption. Na intercalation in g-C3 N4 created an electron transfer path for charge migration. Hydroxyl-modified and Na-intercalated g-C3 N4 exhibited high HCHO removal performance.