Hydrogen peroxide sensing using Ce3+ luminescence of cerium oxide (CeO2-x) nanoparticles

In the paper the new application of nanoceria (CeO2-x nanoparticles) for detection and quantification of hydrogen peroxide (HP) content in water solutions is shown. Sensing of hydrogen peroxide is based on the reversible shift of Ce3+↔ Ce4+ balance in ceria nanoparticles as a result of nanoceria-oxidant interaction. Intensity of 5 d→4f luminescence of Ce3+ ions being a measure of Ce3+/Ce4+ ratio in nanoceria depends linearly on the hydrogen peroxide concentration in water solutions and, so, can be used for reliable quantification of HP content. The nanoceria-based sensor is reversible and applicable for long-term monitoring of oxidant level in biological systems.