2D g-C3N4 as a bifunctional photocatalyst for co-catalyst and sacrificial agent-free photocatalytic N2 fixation and dye photodegradation

Autor: Mohammed Abdullah Bajiri, Abdo Hezam, R. Viswanath, Raghd Alasmari, Ali Alsalme, Nabil Al-Zaqri, Fahad A. Alharthi, H. S. Bhojya Naik
Rok vydání: 2021
Předmět:
Zdroj: New Journal of Chemistry. 45:7174-7184
ISSN: 1369-9261
1144-0546
Popis: Photocatalytic N2 fixation is an ecofriendly technology to produce ammonia. In this work, photocatalytic N2 fixation to generate ammonia in the absence of any co-catalysts or sacrificial agents (SF) is achieved on 2D g-C3N4 prepared via thermal exfoliation, for the first time. The formation of 2D g-C3N4 is confirmed using several analytical techniques including XRD, SEM, TEM, FT-IR, and XPS analyses. 2D g-C3N4 exhibits a blue shift in the bandgap compared to the bulk g-C3N4 attributed to the quantum confinement effect. In the absence of SF, 2D g-C3N4 shows an NH3 production rate of 3.9 mg L−1 h−1 under sunlight irradiation, while no NH3 is generated on bulk g-C3N4. In the presence of ethanol as a sacrificial agent, 2D g-C3N4 also exhibits a higher NH3 production rate (12.76 mg L−1 h−1) than bulk g-C3N4 (7.58 mg L−1 h−1). Moreover, 2D g-C3N4 shows superior photodegradation activity compared to bulk g-C3N4 toward the decomposition of methylene blue (MB) and malachite green (MG) under sunlight irradiation. The enhanced photocatalytic activity of 2D g-C3N4 could be attributed to its more exposed active sites, high charge separation, and low electron–hole recombination rate.
Databáze: OpenAIRE