The energy harvesting provided by wearable triboelectric devices represents a promising procedure that circumvents typical drawbacks of conventional batteries in several applications. The development of wearable triboelectric generators with modified cotton in the presence of conductive and antibacterial agents can be considered an important step toward developing autonomous devices to be applied in electrically driven antibacterial treatments. The antibacterial properties of polypyrrole and its high conductivity were explored for the production of the induction layer of a single-electrode triboelectric generator that introduces advantages relative to direct contact with the skin, which is critical for the treatment of several infections. The open-circuit voltage in the order of 670 V and inhibition haloes in the order of 17 mm (against Staphylococcus aureus) confirm the multifunctional activity of the modified cotton that can be applied to the harvesting of energy and integrated into the inhibition of bacterial growth provided by polypyrrole-based systems.

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A biomass amino silica-functionalized material was successfully prepared by a simple sol–gel method. 3-Aminopropyltriethoxysilane (APTES) was added to a tannin-rich grape residue to improve its physicochemical properties and enhance the adsorption performance. The APTES functionalization led to significant changes in the material’s characteristics. The functionalized material was efficiently applied in the removal of methyl orange (MO) due to its unique characteristics, such as an abundance of functional groups on its surface. The adsorption process suggests that the electrostatic interactions were the main acting mechanism of the MO dye removal, although other interactions can also take place. The functionalized biomass achieved a very high MO dye maximum adsorption capacity ( Q max ) of 361.8 mg g –1 . The temperature positively affected the MO removal, and the thermodynamic studies indicated that the adsorption of MO onto APTES-functionalized biomass was spontaneous and endothermic, and enthalpy is driven in the physisorption mode. The regeneration performance revealed that the APTES-functionalized biomass material could be easily recycled and reused by maintaining very good performance even after five cycles. The adsorbent material was also employed to treat two simulated dye house effluents, which showed 48% removal. At last, the APTES biomass-based material may find significant applications as a multifunctional adsorbent and can be used further to separate pollutants from wastewater.

The required treatment and monitoring of contaminants in wastewater reinforces the development of low-cost adsorbents/ chemosensors, introducing advantages relative to the detection/removal of toxic metals and dyes. Herein, it is reported a two-step process of fabrication of fluorescent carbon dots via the hydrothermal treatment of amino acids for the following encapsulation in electrospun fibers. The prominent anionic behavior of electrospun fibers of Eudragit L100 was explored for adsorption of cationic dyes (methylene blue and crystal violet)-with the prevailing electrostatic interaction of parts being favored by the formation of monolayers on the surface of adsorbents. On the other hand, the controlled release of carbon dots (CDs) from fibers to the reactor can be explored for a second application: the nitrogen ligands from released glycinebased carbon dots can be explored to indicate the presence of metal ions in aqueous solution. Our experiment resulted in a quenching in the fluorescence of the CDs in order of 90% in the emission of particles in the response of the presence of Fe 3+ ions, characterizing a promising perspective for this experimental system.

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