Attuning doped ZnO-based composites for an effective light-driven mineralization of pharmaceuticals via PMS activation.

Water treatment technologies need to go beyond the current control of organic contaminants and ensure access to potable water. However, existing methods are still costly and often inadequate. In this context, novel catalysts that improve the mineralization degree of a wider range of pharmaceuticals through more benign and less consuming methodologies are highly sought after. ZnO, especially when doped, is a well-known semiconductor that also excels in the photocatalytic removal of persistent organic pollutants. In this study, we investigated the effect of doping ZnO nanoparticles with either copper, gallium or indium on the structure, morphology, photophysical properties and photocatalytic mineralization of pharmaceuticals. Their architecture was further improved through the fabrication of composites, pairing the best performing doped ZnO with either BaFe12O19 or nickel nanoparticles. Their suitability was tested on a complex 60-ppm multi-pollutant solution (tetracycline, levofloxacin and lansoprazole). The activation strategy combined photocatalysis with peroxymonosulfate (PMS) as an environmentally friendly source of highly oxidative sulfate radicals. The alliance of doped ZnO and BaFe12O19 was particularly successful, resulting in magnetic microcroquette-shaped composites with excellent inter-component synergy. In fact, indium outperformed the other proposed metal dopants, exceeding 97% mineralization after 1 h and achieving complete elimination after 3 h. All composites excelled in terms of reusability, with no catalytic loss after 10 consecutive cycles and minimal leakage of metal ions, highlighting their applicability in water remediation.

Advanced degradation of organic pollutants using sonophotocatalytic peroxymonosulfate activation with CoFe2O4/Cu- and Ce-doped SnO2 composites.

The rampant upsurge of organic pollutants in aqueous media has become one of the major concerns nowadays. Finding non-specific catalysts that can target a wide range of organic pollutants is a key challenge. Eco-friendly oxidative radicals, such as promoted by peroxymonosulfate (PMS), are necessary for efficient water decontamination. We propose a multicomponent composite catalyst for activating PMS using a dual strategy of sonophotocatalysis. The composite integrates cobalt ferrite and Cu- or Ce-doped SnO2, with the at. % of doping metal and the mixture ratio carefully balanced. The top-performing architectures were able to decompose rhodamine B (20 ppm), a representative pollutant, in under 3 min and achieve over 70% mineralization in just 5 min. The synthesized nanocomposites demonstrated exceptional sonophotocatalytic performance, even when treating complex and diverse multipollutant solutions (80 ppm), achieving over 75% mineralization after 150 min. Considering their high stability and reusability, the proposed CoFe2O4/Cu- and Ce-doped SnO2 materials are among the state-of-the-art heterogeneous catalysts for mineralizing organic pollutants through PMS activation.

Powder X-ray diffraction as a powerful tool to exploit in organic electronics: shedding light on the first N,N',N''-trialkyldiindolocarbazole.

The first crystal structure of a fully N-alkylated diindolocarbazole derivative, namely, 5,8,14-tributyldiindolo[3,2-b;2',3'-h]carbazole (1, C36H39N3), has been determined from laboratory powder X-ray diffraction (PXRD) data. A complex trigonal structure with a high-volume unit cell of 12987 Å3 was found, with a very long a(=b) [52.8790 (14) Å] and a very short c [5.36308 (13) Å] unit-cell parameter (hexagonal setting). The detailed analysis of the intermolecular interactions observed in the crystal structure of 1 highlights its potential towards the implementation of this core as a semiconductor in organic thin-film transistor (OTFT) devices. Since the molecule has a flat configuration reflecting its π-conjugated system, neighbouring molecules are found to stack atop each other in a slipped parallel fashion via π-π stacking interactions between planes of ca 3.30 Å, with a centroid-centroid distance between the aromatic rings corresponding to the shortest axis of the unit cell (i.e. c). The alkylation of the three N atoms proves to be a decisive feature since it favours the presence of C-H...π interactions in all directions, which strengthens the crystal packing. As a whole, PXRD proves to be a valuable option for the resolution of otherwise inaccessible organic crystal structures of interest in different areas.

Towards the Bisbenzothienocarbazole Core: A Route of Sulfurated Carbazole Derivatives with Assorted Optoelectronic Properties and Applications.

Ladder-type molecules, which possess an extended aromatic backbone, are particularly sought within the optoelectronic field. In view of the potential of the 14H-bis[1]benzothieno[3,2-b:2',3'-h]carbazole core as a p-type semiconductor, herein we studied a set of two derivatives featuring a different alkylation patterning. The followed synthetic route, involving various sulfurated carbazole-based molecules, also resulted in a source of fluorophores with different emitting behaviors. Surprisingly, the sulfoxide-containing fluorophores substantially increased their blue fluorescence with respect to the nearly non-emitting sulfur counterparts. On this basis, we could shed light on the relationship between their chemical structure and their emission as an approach for future applications. Considering the performance in organic thin-film transistors, both bisbenzothienocarbazole derivatives displayed p-type characteristics, with hole mobility values up to 1.1 × 10-3 cm2 V-1 s-1 and considerable air stability. Moreover, the role of the structural design has been correlated with the device performance by means of X-ray analysis and the elucidation of the corresponding single crystal structures.