Novel broad-spectrum-driven oxygen-linked band and porous defect co-modified orange carbon nitride for photodegradation of Bisphenol A and 2-Mercaptobenzothiazole

Abstract

Here, we successfully synthesized the oxygen-linked band and porous defect co-modified orange carbon nitride (AF-C₃N₄) using a simple method. Further, the band structure calculation of its simulated structure is performed by DFT, which shows that the introduction of oxygen-linked band can adjust its band structure. The photocatalytic degradation rates of 0.3AF-C₃N₄ for bisphenol A and 2-mercaptobenzothiazole were 8 times and 2.73 times that of the original g-C₃N₄, respectively. Moreover, 0.3AF-C₃N₄ also shows photocatalytic activity under different wavelength light (blue, green and red light), which indicates that the synthesized materials have a broad spectrum of photocatalytic activity. Further, we proposed a possible photocatalytic degradation pathway by HPLC-MS analysis. Free radical quenching test and ESR spectra show that the generated superoxide radicals (•O₂^-), hydroxyl radicals (•OH) and holes (h⁺) cause photodegradation, while enhancing singlet oxygen (¹O₂) and weaken the content of hydrogen peroxide has further proved that active oxygen groups play an important role in the photocatalytic degradation process. Additionally, the 0.3AF-C₃N₄ can also be a photoelectrochemical sensor to detect the concentration of bisphenol A (λ ≥ 550 nm). This study provides a new strategy for the synthesis of orange carbon nitride by oxygen-linked band and porous defect co-modification for photocatalytic applications.

Keywords: 2-Mercaptobenzothiazole; AF-C(3)N(4); Bisphenol A; Degradation; Photocatalysis.