Photocatalytic Degradation of Selected Pharmaceuticals Using g-C3N4 and TiO2 Nanomaterials

Abstract

Exfoliated graphitic carbon nitride (g-C3N4) and two commercially available nanomaterials from titanium dioxide (P25 and CG300) were tested for the photocatalytic degradation of paracetamol (PAR), ibuprofen (IBU), and diclofenac (DIC). Prior to photocatalytic experiments, the nanomaterials were characterized by common methods, such as X-ray diffraction (XRD), UV–VIS diffuse reflectance spectroscopy (DRS), Fourier transformed infrared spectroscopy in attenuated total reflection mode (FTIR–ATR), transmission electron microscopy (TEM), physisorption of nitrogen, and dynamic vapor adsorption (DVS) of water. The sizes and specific surface area (SSA) of the TiO2 nanoparticles were 6 nm and 300 m2·g−1 for CG300 and 21 nm and 50 m2·g−1 for P25. The SSA of g-C3N4 was 140 m2·g−1. All photocatalytic experiments were performed under UV (368 nm), as well as VIS (446 nm) irradiation. TiO2 P25 was the most active photocatalyst under UV irradiation and g-C3N4 was the most active one under VIS irradiation. Photodegradation yields were evaluated by means of high performance liquid chromatography (HPLC) and reaction intermediates were identified using gas chromatography with mass detection (GC–MS). Paracetamol and ibuprofen were totally removed but the intermediates of diclofenac were observed even after 6 h of irradiation. Some intermediates, such as carbazole-1-acetic acid, 2,6-dichloraniline, and hydroxylated derivates of diclofenac were identified. This study showed that g-C3N4 is a promising photocatalyst for the degradation of pharmaceuticals in an aqueous environment, under visible light.

TiO2 nanofibres decorated with green-synthesized PAu/Ag@CQDs for the efficient photocatalytic degradation of organic dyes and pharmaceutical drugs

“…The present work, for the rst time, reports green-synthesized plasmonic nanostructures as an active photosensitizer for the photocatalytic dye and pharmaceutical drug degradation with TiO 2 nanobers, over widely-known applications of CQDs as photosentitizers. [49][50][51][52][53][54][55] The photocatalytic activity of P M -CQD/TiO 2 NC was studied for the degradation of MB dye under a UVvisible light source (250 W). MB exhibits characteristic absorption peaks at 609 nm and 663 nm, and the change in its absorption characteristics w.r.t.…”

N-Doped Carbon-Coated ZnS with Sulfur-Vacancy Defect for Enhanced Photocatalytic Activity in the Visible Light Region

“…The hole radicals located in the CB of ZnS can react with H 2 O molecules to yield ·OH radicals. With the assistance of the above radicals in the visible light region, TCH moleculesare decomposed via the N-C bond cleavage and hydroxylation and further react with ·OH radicals to destroy the C2-C3 double-bond and eliminate NH 3 , and subsequently are disintegrated into small molecules and even H 2 O and CO 2 [35].…”

“…Photocatalysis, as a potential route to relieving environmental and energy issues, has been intensively applied for pollutant degradation [1][2][3][4], water splitting [5][6][7], and solar energy conversion [8][9][10][11]. As a typical metal sulfide, ZnS, which has a large band gap (3.6~3.8 eV), exhibits excellent photocatalytic capacity, owing to its strong oxidation and high negative potentials of excited electrons [12,13].…”

Sonochemical Synthesis of Copper-doped BiVO4/g-C3N4 Nanocomposite Materials for Photocatalytic Degradation of Bisphenol A under Simulated Sunlight Irradiation

“…In addition, g-C 3 N 4 nanosheets could enhance an easier electron transfer during the reaction [9]. Smykalova et al (2019) indicated that g-C 3 N 4 nanosheets possessed a large specific surface area, which resulted in the higher degradation ratio of medicines in water [10]. Zhang et al (2017) indicated that the composite with 7 wt% g-C 3 N 4 had better photocatalytic efficiency than bare BiVO 4 [11].…”