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In this work, reduced Titania (TiO2−x) was obtained by laser ablation of commercial rutile TiO2 powder dispersed in N,N-dimethyl formamide (DMF) using a pulsed Nd:YAG (Neodymium-doped Yttrium Aluminium Garnet) laser (532 nm, 10 ns, 10 Hz). It was observed that DMF solvent was able to promote change in the optical band gap of commercial TiO2 (P25). The Ultraviolet–Visible (UV–vis) absorption measurement showed a shoulder in the infrared region with maximum at 690 nm, characteristic of reduced metal oxide. The electron paramagnetic resonance (EPR) measurements confirmed the presence of oxygen vacancies by the characteristic signal in g = 2.002 g and more intense than water-reduced oxide commonly obtained in other works. The X-ray diffraction (XRD) results show the same crystalline phase to P25 and small shifts due to presence of vacancy’s distorting the TiO2 structure. Scanning electron microscopy (SEM) image have shown surface coalesced particles in comparison to commercial P25, agreeing with nitrogen adsorption measurements which indicated a decrease in the surface area from 10.6 to 6.9 m2/g. The photothermal conversion properties was investigated and the reduced TiO2 samples showed higher temperatures when excited with a laser 785 nm wavelength in function of the strong absorption band and higher vacancy’s concentration.

Here we report a new synergic strategy for the synthesis of metal-organic frameworks (MOFs), the sonoelectrochemical method. The metal-organic framework HKUST-1 [Cu 3 (BTC) 2 (H 2 O) 3 ] n was successfully prepared by using this approach. Structural and morphological properties of HKUST-1 were studied and results compared with those obtained for the same material synthesized via a conventional solvothermal method. The sonoelectrochemical approach allowed the preparation of powder samples with nanosized characteristics, high yields and in a short time. Furthermore, we confirmed that this route worked well for the synthesis of others MOFs, such as ZIF-8 and MIL-53. Such simple and practical strategy may allow the large-scale production of MOFs, which is of great interest for industrial applications.

An electrochemical sensor based on a gold-copper metal-organic framework immobilized on the surface of glassy carbon electrode has been developed for the electrocatalytic oxidation and determination of glutathione. Gold nanoparticles were incorporated into copper-1,3,5-benzenetricarboxylate and the composition and structure of the resulting nanocomposite (Au@Cu-BTC) were verified by transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffractometry, scanning electron microscopy and Fourier transform infrared spectroscopy. Cyclic and square wave voltammetric studies of the electrochemical behavior of glutathione at the modified electrode showed that the incorporation of gold particles increased the conductivity of Cu-BTC. Glutathione was detected by the formation of a Cu (II)-glutathione complex and its subsequent oxidation at ca. + 0.25 V vs. Ag/AgCl. The proposed methodology exhibited a low limit of detection (0.30 μmol L−1) and a wide linear dynamic range (1–10.0 μmol L−1) with good sensitivity (0.89 ± 0.02 μA μmol L―1) and repeatability (2.14 %). The high recovery (98.2 %) obtained in the analysis of a dietary supplement renders this new approach very attractive for the analytical determination of glutathione in commercial samples, particularly if the technique is extended to commercially produced screen-printed electrodes.

The molecular structure of the title compound, C11H13N3S, is not planar: the maximum deviation from the mean plane of the non-H atoms is 0.521 (2) Å for an aliphatic C atom, which corresponds to an envelope conformation for the non-aromatic ring. The hydrazinecarbothioamide substituent and the benzene ring have maximum deviations from the mean planes through the non-H atoms of 0.0288 (16) and 0.0124 (27) Å, respectively, and the dihedral angle between the two planes is 8.84 (13)°. In the crystal, molecules are linked into chains along [1overline{1}0] by pairs of N—H...S hydrogen bonds between molecules related by centres of symmetry.