Pt decorated Cu₂O nanocomposite to detect ppb level Ozone concentration

This study reports the synthesis, characterization, and ozone-sensing performance of platinum (Pt)-decorated cuprous oxide (Cu₂O) nanomaterials at room temperature. Structural and optical analysis confirmed the uniform distribution of Pt nanoparticles (∼4.5 nm) on Cu₂O nanocubes, which effectively reduced the material’s optical bandgap from 2.26 eV to 2.05 eV and facilitated charge transfer. Among various Pt loadings, the 1 wt% Pt/Cu₂O composite exhibited optimal performance, delivering a sensor response of 12.21 to 1 ppm ozone and a low detection limit of 32.8 ppb—over an order of magnitude improvement compared to pristine Cu₂O. The composite also demonstrated excellent long-term stability over 25 days and a reliable, linear response across a range of ozone concentrations. These results indicate that controlled Pt decoration enhances sensitivity by optimizing the trade-off between surface reactivity and electrical conductivity, positioning the 1 wt% Pt/Cu₂O composite as a promising, cost-effective material for ambient ozone monitoring.