A 2D/1D heterojunction nanocomposite built from polymeric carbon nitride and MIL-88A(Fe) derived α-Fe2O3 for enhanced photocatalytic degradation of rhodamine B

• Published in: New journal of chemistry Vol. 46; no. 19; pp. 9064 - 9074
• Main Authors: Viswanathan, Vandana P, Nayarassery, Adarsh N, Xavier, Marilyn Mary, Mathew, Suresh
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 2022
• Subjects: Carbon; Carbon nitride; Catalytic activity; Composite materials; Current carriers; Ferric oxide; Heterojunctions; Hybrid systems; Iron; Metal-organic frameworks; Nanocomposites; Photocatalysis; Photocatalysts; Photodegradation; Recyclability; Rhodamine; Sunlight; Two dimensional analysis
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d1nj05439b

Fabricating heterojunction catalysts is a promising strategy for enhancing the performance of heterogeneous photocatalytic reactions. Based on the nontoxicity and low cost of photocatalyst, we synthesized two dimensional/one dimensional (2D/1D) heterojunction photocatalysts, namely α-Fe2O3/C3N4-x% (FC-x = 4, 8, and 12) containing α-Fe2O3 microrods and polymeric carbon nitride (C3N4) flakes through the calcination of Fe-based metal-organic framework (MIL-88A(Fe)) with C3N4 for boosting visible light photocatalytic degradation of rhodamine B (RhB). The synthesized composite materials are characterized by FTIR, PXRD, UVDRS, PL, FESEM, TEM, BET and TG/GC/MS analysis. Due to the 2D/ID heterojunction formation between C3N4 and α-Fe2O3, the band gap of α-Fe2O3/C3N4 composite (FC-8) is reduced to 2.05 eV compared to C3N4 and α-Fe2O3. The hybrid system α-Fe2O3/C3N4-8% (FC-8) showed excellent photocatalytic activity for the degradation of RhB under sunlight. The hybrid FC-8 shows 92% degradation of RhB in 60 min under sunlight. A possible Z-scheme mechanism for the enhanced photocatalytic activity of the FC-8 composite is also proposed. More importantly, the fabricated 2D/1D heterojunction between α-Fe2O3 and C3N4 efficiently speeds up the transfer and separation of photoinduced charge carriers, which is beneficial for photocatalytic activity. Trapping experiments revealed that superoxide radicals are the prime radicals responsible for the degradation of RhB. The hybrid system FC-8 showed high recyclability and chemical stability.