Anwer H, Park JW. Synthesis and characterization of a heterojunction rGO/ZrO
2/Ag
3PO
4 nanocomposite for degradation of organic contaminants.
JOURNAL OF HAZARDOUS MATERIALS 2018;
358:416-426. [PMID:
30007252 DOI:
10.1016/j.jhazmat.2018.07.019]
[Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 07/03/2018] [Accepted: 07/04/2018] [Indexed: 05/25/2023]
Abstract
Synergy between surface adsorption and photocatalysis is key for effective contaminant degradation in the liquid phase. Herein, we report a heterojunction photocatalyst of reduced graphene oxide (rGO)/zirconium dioxide (ZrO2)/silver phosphate (Ag3PO4) that incorporates this synergy for 4-nitrophenol (PNP) removal. Compared with other photocatalyst combinations, ZrO2 and Ag3PO4 coupling generates reactive species with greater degradation potential. ZrO2 and rGO were synthesized by a green approach using a one-step hydrothermal reaction in ethanol-water. The growth of rGO/ZrO2 and Ag3PO4 were accomplished and the functions of each part were well developed together. The rGO/ZrO2/Ag3PO4 composite exhibited enhanced light absorption and a low band gap energy (2.3 eV) owing to rGO and Ag3PO4 integration. The composite's photocatalytic activity was much higher than that of ZrO2, Ag3PO4, or ZrO2/Ag3PO4. The maximal adsorption of PNP was 26.88 mg/g, and a pseudo-first-order model described the PNP degradation kinetics (k = 0.034 min-1). Synergy between the three components resulted in 97% PNP removal in 90 min, and even after five cycles, 94% PNP removal was obtained. The quantum yield of the system (7.31 × 10-5 molecules/photon) was compared with those in previous reports to assess the photocatalytic performance and energy requirements.
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