Figure 4.

(A) UV–vis absorption spectra of WC-700 flakes, pristine Au grating, and Au grating with deposited WC-700; (B) amounts of hydrogen and oxygen on the Au/WC–X surface as a function of pristine WO₃/CdS annealing temperature (results are given only for solely sunlight-induced water splitting); (C) amounts of hydrogen and oxygen produced on the illuminated Au/WC-700 surface as a function of the light wavelength; and (D) results of comparative measurements—water splitting achieved on the surface of WC-700 flakes not coupled with the plasmon-active substrate.