Household chemicals as key ingredients: the addition of sodium percarbonate to tin chloride in deep eutectic solvents leads to SnO2 nanoparticles very efficient for dye photocatalytic degradation

The combination of Deep Eutectic Solvents and inorganic synthesis has one of its highest expressions in the preparation of functional materials endowed with remarkable features and ensuing technological properties. In this contribution, we present a new simple and low-cost synthetic approach to synthesize tin dioxide nanoparticles in deep eutectic solvent reline that improves the method reported in the literature, which leads to tin monoxide. The new strategy is based on the addition of a readily available and low-cost oxidizing additive found in household materials (sodium percarbonate), and leads exclusively to high-purity dioxide. The two samples prepared (dioxide and control monoxide) were fully characterized with structural, spectroscopic and microscopy techniques. Both systems were found to contain bidimensional nanostructures, namely larger platelets aggregated in ice-cream scoops-like domains in SnO, and smaller low nm-range lozenges pillared on top of each other in SnO 2 . Both oxides were tested as photocatalysts in the degradation of crystal violet dye in various conditions, obtaining exceptional results for tin dioxide in terms of degradation times, remarkably shorter than literature values. • SPC addition to eco-friendly DES media leads to SnO 2 NPs with large specific surface. • SPC creates a highly oxidizing environment within DES, preventing its air shielding. • SnO 2 scores an impressive 96% dye reduction under UV light in only 21 min. • The fast and low-waste synthesis can be performed also in low-resource settings. • Good dye-removal activity is recognized in both SnO and SnO 2 nanoparticles.