In this study, two copper(II) complexes, [Cu(C6H8N3S2)2]Cl2 (1) and [Cu(C7H10N3S2)2]Cl2·H2O (2), were synthesized from 2-(thiophen-2-ylmethylene)hydrazine-1-carbothioamide (L1H) and 2-(1-(thiophen-2-yl)ethylidene)hydrazine-1-carbothioamide (L2H) respectively and characterized using various spectroscopic techniques and elemental analyses. The as-prepared complexes were used as single-source precursors for the synthesis of oleylamine-capped (OLA@CuxSy), hexadecylamine-capped (HDA@CuxSy), and dodecylamine-capped (DDA@CuxSy) copper sulphide nanoparticles (NPs) via the thermolysis method at 190 °C and 230 °C and then characterized using powder X-ray diffraction (p-XRD), UV-visible spectroscopy, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The p-XRD diffraction patterns confirmed the formation of crystalline rhombohedral digenite Cu9S5 with the space group R-3m. The TEM images showed the formation of nanoparticles of various shapes including hexagonal, rectangular, cubic, truncated-triangular, and irregularly shaped Cu9S5 nanomaterials. The SEM results showed aggregates and clusters as well as the presence of pores on the surfaces of nanoparticles synthesized at 190 °C. The UV-visible spectroscopy revealed a general blue shift observed in the absorption band edge of the copper sulphide NPs, as compared to bulk CuxSy, with energy band gaps ranging from 2.52 to 3.00 eV. Energy-dispersive X-ray spectroscopy (EDX) confirmed the elemental composition of the Cu9S5 nanoparticles. The nanoparticles obtained at 190 °C and 230 °C were used as catalysts for the photocatalytic degradation of methylene blue (MB) under UV irradiation. Degradation rates varying from 47.1% to 80.0% were obtained after 90 min of exposure time using only 10 mg of the catalyst, indicating that Cu9S5 nanoparticles have potential in the degradation of organic pollutants (dyes).

This article reports on VIS-active composite thin films based on zinc oxide (ZnO) and copper sulfide (CuxS) deposited using robotic spray pyrolysis deposition (SPD) for the study of the optical and photocatalytic properties. The first step involves the SPD deposition of a CuxS layer onto the glass substrate at 300°C. The second step consists of the deposition of a ZnO layer onto the CuxS layer to form glass/CuxS-ZnO composites that were further annealed at 400°C. The development of the composite thin films was confirmed by XRD and EDX analyses. The band gap energy ( E g ) of the bare ZnO thin films decreased from 3.15 eV to an activation energy value of 2.8 eV after the deposition of the ZnO thin layer onto the CuxS layer and from 2.8 to 2.08 eV after annealing the CuxS-ZnO composite at 400°C. The UV-VIS irradiation (5.5% of UV, G = 55   W / m 2 ) of a 10 ppm methylene blue solution was used to investigate the photocatalytic properties of the CuxS-ZnO composites. The annealed CuxS-ZnO thin films at 400°C demonstrates better photocatalytic activity compared to CuxS-ZnO composites deposited at 300°C. The enhanced photocatalytic efficiency of the annealed CuxS-ZnO thin films may be the result of the diode structure and the increased crystallinity that prevent the electron-hole recombination.

Ni(II), Cu(II), and Zn(II) complexes of the tridentate heterocyclic ligand, 2-(phenyl(pyridin-2-yl)methylene)hydrazine-1-carbothioamide (HL) have been synthesized and characterized by various spectroscopic techniques and elemental analyses. Infrared spectroscopy shows that the ligand coordinates to the metal ions through the azomethine and pyridine nitrogen atoms as well as the sulfur atom of the thioamide group to form a tridentate chelate system. In vitro screening of metal complexes against four bacterial strains (Staphylococcus aureus (ATCC 43300), Klebsiella pneumoniae (ATCC 700603), Methicillin resistant staphylococcus aureus (ATCC 33591), Shigella flexneri (NR 518)) and four fungal strains (Candida albicans (NR 29444), Candida albicans (NR 29445), Candida albicans (NR 29451), Candida krusei (HM 1122)) indicate that the Cu(II) complex showed good antibacterial activity on Methicillin resistant staphylococcus aureus (ATCC 33591) while the Zn(II) complex showed moderate activity against some of the bacterial and fungi strains. Antioxidant studies reveal that the complexes are more potent than the ligand to eliminate free radicals, with the Ni(II) complex showing the best free radical scavenger.