Immobilized TiO2/ZnO Sensitized Copper (II) Phthalocyanine Heterostructure for the Degradation of Ibuprofen under UV Irradiation

Abstract

Photocatalytic coatings of TiO2/ZnO/CuPc were developed on stainless steel substrates by subsequent sol gel dip coating for TiO2, spray pyrolysis for ZnO, and spin coating for copper (ii) phthalocyanine (CuPc) deposition. The latter compound was successfully prepared using a Schiff-based process. The materials and coatings developed were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy with attached energy dispersive spectroscopy (SEM-EDS), UV-Vis spectroscopy, room temperature photoluminescence (RTPL) spectroscopy, H1-nuclear magnetic resonance (1H-NMR) spectroscopy, C13-nuclear magnetic resonance (13C-NMR) spectroscopy, and matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS). The as-deposited TiO2/ZnO/CuPc on stainless steel retained in pristine state the structural and morphological/spectroscopic characteristics of its respective components. Estimated energy band gap values were 3.22 eV, 3.19 eV, 3.19 eV for TiO2, ZnO, TiO2/ZnO respectively and 1.60 eV, 2.44 eV, and 2.92 eV for CuPc. The photocatalytic efficiency of the fabricated TiO2/ZnO/CuPc coatings was tested toward ibuprofen (IBF). After 4 h irradiation under 365 nm UV, an increased degradation of about 80% was achieved over an initial 5 mg/L ibuprofen (IBF). This was much higher compared to about 42% and 18% IBF degradation by TiO2/ZnO and TiO2 thin film, respectively. In all cases, the stability of the best-performing photocatalyst was investigated showing a small decline to 77% of IBF degradation after the 5th cycle run. The effect of pH, reactive oxygen species (ROS) probe, shed light on a possible catalytic mechanism that was suggested.

Oxidative Degradation of Pharmaceuticals: The Role of Tetrapyrrole-Based Catalysts

“…These semiconductor-promoted oxidation mechanisms are complementary to the ROS formation pathways mentioned above for the TPM-based catalysts and thus potentiate drug degradation. [1,13] Thus, a significant portion of the work developed in this field has been focused on the development of hybrid catalysts comprising TPM immobilized in semiconductors [2,[14][15][16][17][18][19][20][21][22].…”

“…Anucha and Altin [15] developed the material CuPc(th) 4 @TiO 2 /ZnO by modifying TiO 2 and ZnO semiconductor blends with thiazol tetrasubstituted copper phthalocyanine (CuPc(th) 4 , Figure 6). This hybrid material was evaluated on the photodegradation of ibuprofen (IBU, Figure 5) in an aqueous matrix using five mercury lamps of 40 W at 365 nm (Table 3, entry 3).…”

“…Figure15. Schematic illustration of the proposed visible-light photocatalysis mechanism for FAM degradation using TCPP@ATiNT and TCPP@Si-ATiNT.…”

Silver Doped Zinc Stannate (Ag-ZnSnO3) for the Photocatalytic Degradation of Caffeine under UV Irradiation

“…Unprecedented waste inflow from rural and urban households as well industrial companies has led to the pollution of the aquatic environment [2][3][4][5]. Amongst several sources of water environmental pollution, contaminants of emerging concerns (CECs) remain alarming and issue of public concern [3,[5][6][7]. These are chemicals encompassing wide range of organic products from pharmaceuticals and personal healthcare products (PPCPs) to organic solvents, to flame retardants, to synthetic chemicals, to pesticides, etc.…”

Rational Design of Non-Precious Metal Oxide Catalysts by Means of Advanced Synthetic and Promotional Routes

“…The latter can be accomplished by the employment of state-of-the-art nano-synthesis routes towards engineering particle's size and shape (e.g., nanocubes, nanorods) in conjunction to the use of appropriate modifiers (e.g., alkali, graphene oxide) and special pretreatment protocols. This holistic approach can exert a profound influence not only to the surface reactivity of metal sites in its own right, but also to metal-support interfacial activity, offering highly active and stable materials for real-life energy and environmental applications, such as the CO oxidation [7][8][9][10][11][12], N 2 O decomposition [13][14][15], CO 2 hydrogenation to value-added products [16][17][18][19][20], degradation of organic contaminants [21][22][23][24][25][26][27][28][29][30][31][32][33], etc.…”