Ag-Functionalized CuWO/WO nanocomposites for solar water splitting

• Published in: New journal of chemistry Vol. 43; no. 5; pp. 2196 - 223
• Main Authors: Salimi, R, Sabbagh Alvani, A. A, Mei, B. T, Naseri, N, Du, S. F, Mul, G
• Format: Journal Article
• Language: English
• Published: 28.01.2019
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c8nj05625k

Ag-Functionalized CuWO 4 /WO 3 heterostructures were successfully prepared via a polyvinyl pyrrolidone (PVP)-assisted sol-gel (PSG) route. Thin films prepared via electrophoretic deposition were used as photoanodes for photoelectrochemical (PEC) water splitting. Compared to pristine CuWO 4 and WO 3 films, a significant enhancement of the photocurrent (3-4 times) at the thermodynamic potential for oxygen evolution (0.62 V vs. Ag/AgCl, pH 7) was obtained for the Ag-functionalized CuWO 4 /WO 3 photoanodes. The obtained enhancement is shown to be derived from a synergic contribution of heterostructure formation (CuWO 4 /WO 3 ) and improvements of light utilization by Ag-induced surface plasmon resonance (SPR) effects. Accordingly, a photocurrent of 0.205 mA cm −2 at 0.62 V vs. Ag/AgCl under neutral conditions (without hole scavengers) under front-side simulated AM1.5G illumination was achieved. A detailed analysis of the obtained PEC data alongside performed impedance measurements suggests that charge seperation is significantly improved for the prepared Ag-functionalized CuWO 4 /WO 3 photoanodes. Our work offers beneficial insights to design new plasmonic metal/heterostructured nanocomposites for energy conversion applications. A new plasmonic Ag-functionalized CuWO 4 /WO 3 hetero-structured photoanode was successfully prepared via a PVP-assisted sol-gel (PSG) route and electrophoretic deposition which reveals 4 times enhanced photocurrent density compared with pristine WO 3 .