In situ infrared CO detection using silver loaded EMT zeolite films

Ag cluster catalyst-based oxidation of CO to CO(2) is an important way to remove CO at low temperatures. However, the instability of silver clusters seriously limits the catalytic application. Herein, sub-nanosized EMT zeolite nanoparticles served as Ag cluster carriers with high selectivity, low coordination, and unsaturated atom active sites. The silver clusters with sub-nanometer size can be controlled with different charge states and loading rates. A detection film with 500 nm was further prepared by assembling the Ag-EMT composites with a small amount of Nalco as an adhesive. For CO detection, a completely enclosed gas sensing device based on in situ infrared spectroscopy was employed without air interference. CO was accurately introduced into the detection chamber and catalysed into CO(2) by silver loaded EMT zeolite films, and the whole process was accurately recorded by infrared spectroscopy. CO with a detection range of 2–50 ppm was realized, showing great application potential in gas monitoring.