Effects of copper precursor concentration on the growth of cupric oxide nanorods for photoelectrode using a modified chemical bath deposition method

•CuO nanorod photoelectrodes were prepared by modified CBD method.•The CuO nanorods were vertically grown with a high growth rate.•Effects of precursor concentration on the CuO nanorods were investigated.

In this study, vertically aligned CuO nanorods were grown using a modified chemical bath deposition method with various copper precursor concentrations. The morphological, structural, optical and photoelectrochemical properties of the synthesized CuO samples were characterized using a field-emission scanning electron microscope, an X-ray diffractometer, a UV–visible spectrometer and a three-electrode potentiostat, respectively. The growth rates of the samples varied from 4.3 to 500 nm/min with the varying precursor concentrations. The vertically well-grown CuO nanorods exhibited one-dimensional growth along the (0 2 0) plane. We obtained a maximum photocurrent density of −1.05 mA/cm2 at −0.6 V (vs. SCE) from the CuO nanorod photoelectrode grown using the 10 mM copper precursor concentration.