Luminescent carbon dots assembled SBA-15 and its oxygen sensing properties

A simple, environmentally friendly and cost-effective approach has been developed to assemble luminescence carbon dots (CDs) into the ordered channels of the mesoporous SBA-15. When analyzing the effect of gases such as nitrogen, oxygen, carbon dioxide and water vapor in the air on the luminescent properties of CDs/SBA-15 hybrid material, we found that the as-prepared samples had a reversible oxygen sensing signal and good photochemical stability. The samples had no response to carbon dioxide, or nitrogen, indicating that the material has extremely high selectivity to the oxygen over the other gases, and water vapor had almost no effect on the luminescent properties of the CDs/SBA-15 material. The response time was determined to be about 7–10   s and the emission intensities of the samples were effectively reduced as the concentration of oxygen increased. These results indicate that the system we have developed can be used for oxygen detection in wide concentration range and is especially accurate for very low oxygen concentrations.