Abstract
The construction of surface defects on semiconductor oxide photoanodes has been identified as a promising route for attaining improved photoelectrochemical (PEC) performance. Here, Ar plasma treatment has been used to etch the surface of hydrothermally synthesized WO3 nanoplate array films, which generated surface oxygen vacancies (Ovs) with the concomitant reduction of surface W6+ to W5+/W4+. As a result, the visible-light absorption and photogenerated charge separation of WO3 was enhanced, as evidenced by X-ray photoelectron spectroscopy (XPS), UV/Vis diffuse-reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. A WO3 photoanode subjected to Ar plasma treatment for 120 s exhibited a photocurrent density of 1.32 mA cm−2 and an O2 evolution rate of 1.0 μmol cm−2·min−1 under simulated solar light irradiation at a bias potential of 1.23 V vs. reversible hydrogen electrode, approximately 1.7- and 5-times higher, respectively, than those of a pristine sample. This improvement is mainly attributed to the facilitative effect of surface oxygen vacancy defects, which promote electron–hole generation and separation rates and decrease the interfacial charge-transfer resistance between the WO3 photoanode and electrolyte. Our Ar plasma surface modification also has potential for developing other photoanodes for efficient PEC performance.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
