Hierarchical CdS Nanorod@SnO2 Nanobowl Arrays for Efficient and Stable Photoelectrochemical Hydrogen Generation

Wenhui Wang; Can Jin; Limin Qi

doi:10.1002/smll.201801352

Hierarchical CdS Nanorod@SnO₂ Nanobowl Arrays for Efficient and Stable Photoelectrochemical Hydrogen Generation

Small. 2018 Jul 19:e1801352. doi: 10.1002/smll.201801352. Online ahead of print.

Authors

Wenhui Wang¹, Can Jin¹, Limin Qi¹

Affiliation

¹ Beijing National Laboratory for Molecular Sciences, College of Chemistry, Peking University, Beijing, 100871, China.

PMID: 30027578
DOI: 10.1002/smll.201801352

Abstract

An efficient photoanode based on CdS nanorod@SnO₂ nanobowl (CdS NR@SnO₂ NB) arrays is designed and fabricated by the preparation of SnO₂ nanobowl arrays via nanosphere lithography followed by hydrothermal growth of CdS nanorods on the inner surface of the SnO₂ nanobowls. A photoelectrochemical (PEC) device constructed by using this hierarchical CdS NR@SnO₂ NB photoanode presents significantly enhanced performance with a photocurrent density of 3.8 mA cm^-2 at 1.23 V versus a reversible hydrogen electrode (RHE) under AM1.5G solar light irradiation, which is about 2.5 times higher than that of CdS nanorod arrays. After coating with a thin layer of SiO₂ , the photostability of the CdS NR@SnO₂ NB arrays is greatly enhanced, resulting in a stable photoanode with a photocurrent density of 3.0 mA cm^-2 retained at 1.23 V versus the RHE. The much improved performance of the CdS NR@SnO₂ NB arrays toward PEC hydrogen generation can be ascribed to enlarged surface area arising from the hierarchical nanostructures, improved light harvesting owing to the NR@NB architecture containing multiple scattering centers, and enhanced charge separation/collection efficiency due to the favorable CdS-SnO₂ heterojunction.

Keywords: cadmium sulfide; nanosphere lithography; nanostructure arrays; photoelectrochemical hydrogen production; tin oxide.