The use of Short Time on Stream (STOS) transient kinetics to investigate the role of hydrogen in enhancing NOx reduction over silver catalysts

► Short Time on Stream (STOS) is a very useful technique in mechanistic investigations. ► Surface NOx species have been identified by STOS and DRIFTS techniques. ► Potentially reactive and relatively inactive NOx species are differentiated. ► At 250 °C, H2 triggers a decrease in adNOx species and a dramatic increase in N2 production.