ZnSnO3 nanoparticles: Synthesis, physicochemical properties, improved gas sensing, and solar-light photocatalytic activity

There is currently a strong demand for cost-effective and sustainable multifunctional materials for environmental applications. Efficient detection of air pollutants and removal of contaminants from water are critical for both human health and environmental protection. In this context, the development of materials that combine gas sensing with photocatalytic capabilities is particularly valuable. In this work, ZnSnO 3 nanoparticles were synthesized via a simple hydrothermal method characterized by abundant oxygen vacancies. The ZnSnO 3 -based sensor demonstrated efficient ozone detection, operating at an ultra-low input voltage of 0.1 V at room temperature and detecting concentrations as low as 6 ppb, with excellent selectivity and a fast response time of 60 s. Additionally, ZnSnO 3 exhibited strong photocatalytic activity, degrading 90 % of 10 ppm methylparaben (MP) under AM1.5G-filtered solar light within 2 h, primarily via hydroxyl and superoxide radical pathways. These results highlight ZnSnO 3 's promise as a dual-function material for sustainable environmental applications. • ZnSnO 3 nanoparticles with a high concentration of oxygen vacancies. • ZnSnO 3 as sensing element exhibited high sensitivity for ozone detection down to 6 ppb. • Excellent selectivity, repeatability, and fast response to low ozone concentrations, under a low input voltage of 0.1V and at room temperature. • ZnSnO 3 nanoparticles demonstrated ∼90 % degradation efficiency for methylparaben under simulated solar light. • Scavenger experiments confirmed h + and O 2 . • - as the primary active species in the photocatalytic mechanism.