Abstract: | This work reports on an assembling–calcining method for preparing gold–metal oxide core–satellite nanostructures, which enable surface‐enhanced Raman spectroscopic detection of chemical reactions on metal oxide nanoparticles. By using the nanostructure, we study the photooxidation of Si?H catalyzed by CuO nanoparticles. As evidenced by the in situ spectroscopic results, oxygen vacancies of CuO are found to be very active sites for oxygen activation, and hydroxide radicals (*OH) adsorbed at the catalytic sites are likely to be the reactive intermediates that trigger the conversion from silanes into the corresponding silanols. According to our finding, oxygen vacancy‐rich CuO catalysts are confirmed to be of both high activity and selectivity in photooxidation of various silanes. |