Controllable in Situ Surface Restructuring of Cu Catalysts and Remarkable Enhancement of Their Catalytic Activity

Supported metal catalysts play a pivotal role in the production of fuels and chemicals and environmental remediation. However, identification and tailoring of the active metal sites on these catalysts still remain a formidable challenge, primarily due to their dynamic nature in catalytic reactions. Here, we report a simple and effective strategy for tuning supported Cu nanoparticles via controllable in situ surface restructuring to form coordinatively more unsaturated Cu sites, which exhibit a 4-fold increase in catalytic turnover rate and high stability, as probed by the ethanol dehydrogenation reaction. In situ measurements by transmission electron microscopy and X-ray absorption spectroscopy reveal intense phase transformation and consequent dynamic restructuring of Cu nanoparticles, induced by oxidation with temporarily added nitrous oxide and subsequent reduction under reaction conditions. Such restructuring is precisely controlled at the Cu surfaces without altering Cu dispersion, oxidation state, e...