Title : Using X ray absorption spectroscopy (XAS) to probe single atom catalysts in carbon nanotubes
ingle-atom catalysts (SACs) are the smallest entities for catalytic reactions with high atomic efficiency, activity, and selectivity. However, practical applications of SACs are limited by single atom loading of less than 2 wt.% or alternatively aggregation of the SACs to form larger particles, e.g. nanoparticles. In our research we have developed a class of SACs based strictly on atomically dispersed transition metals on nitrogen-doped carbon nanotubes and characterised these using a variety of complementary methods, including X-ray absorption spectroscopy (XAS) at the Australian Synchrotron in Melbourne. This material contains up to 20 wt.% SACs [Yi Cheng et al, Adv. Mater. 30 (2018) 1706287]. In our presentation we will focus on the characterization aspect of the material with particular emphasis on XAS; sample preparation, data collection, and interpretation.