CuO nanorod arrays by gas-phase cation exchange for efficient photoelectrochemical water splitting

CuO has been considered a promising candidate for photoelectrochemical water splitting electrodes owing to its suitable bandgap, favorable band alignments, and earth-abundant nature. In this paper, a novel gas-phase cation exchange method was developed to synthesize CuO nanorod arrays by using ZnO nanorod arrays as the template. ZnO nanorods were fully converted to CuO nanorods with aspect ratios of 10-20 at the temperature range from 350 to 600 degrees C. The as-synthesized CuO nanorods exhibit a photocurrent as high as 2.42 mA cm(-2) at 0 V vs. RHE (reversible hydrogen electrode) under 1.5 AM solar irradiation, demonstrating the potential as the photoelectrode for efficient photoelectrochemical water splitting. Our method provides a new approach for the rational fabrication of high-performance CuO-based nanodevices.

Automated summary

In this study, CuO nanorod arrays were synthesized using a novel gas-phase cation exchange method with ZnO nanorod arrays as the template. The synthesized CuO nanorods exhibited a high photocurrent of 2.42 mA cm(-2) under solar irradiation, demonstrating their potential as efficient photoelectrochemical water splitting electrodes.