• PDF / 2,214,967 Bytes
• 17 Pages / 595.276 x 790.866 pts Page_size
• 19 Downloads / 266 Views

DOWNLOAD

REPORT

---

ZnO/CuO hybrid films synthesized by sequential application of electrochemical and spin coating technique Go¨kmen Sıg˘ırcık1,* 1

and Tunc¸ Tu¨ken1

Chemistry Department, Faculty of Science and Letters, Çukurova University, 01330 Adana, Turkey

Received: 9 May 2020

ABSTRACT

Accepted: 25 August 2020

The synthesis of ZnO/CuO films on ITO substrate was realized in two steps, first ZnO was deposited electrochemically and then CuO nanoparticles were precipitated with help of spin coating technique. ZnO nanorods were obtained in aqueous Zn(NO3)2 solution, in presence of KCl as capping agent. Spin coating technique yielded CuO nanoparticles on these nanorods, particle size was employed by copper (II) acetate and ethanolamine in 2-methoxyethanol. In addition, field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy studies were also realized for understanding the structure. UV–Visible spectrophotometer study results revealed that the bandgap value of bilayered structure was governed by presence of CuO nanoparticles. Mott–Schottky analysis was realized for characterization of prepared semiconductor materials, which indicated to ? 0.571 for ZnO/CuO(3), while these values were ? 0.532 V and - 0.360 V for CuO and ZnO, respectively. Electrochemical measurements were realized with help of solar simulator, for testing photocatalytic activity of ZnO/CuO as photocathode material, in aqueous solution.

Ó

Springer Science+Business

Media, LLC, part of Springer Nature 2020

1 Introduction Water splitting by means of photoelectrochemical (PEC) cells is an exciting method for hydrogen production, which involves new generation anode/cathode materials with high catalytic efficiency and economy [1–3]. Semiconductor photoelectrodes have been extensively studied to improve their efficiency under day light [4, 5]. Zinc oxide has frequently been pronounced as a strong candidate,

Address correspondence to E-mail: [email protected]

https://doi.org/10.1007/s10854-020-04339-x

because of its compatible exciton binding energy (60 meV), high chemical/thermal stability, and good electron mobility [6, 7]. Besides, ZnO is an n-type semiconductor material with low cost and environmental friendly nature [8, 9]. ZnO includes a positive effect on catalytic performance due to its good electrical conductivity, high transparency, and relatively high surface region that depends on synthesis condition [10]. ZnO can be synthesized in diverse structure between one dimensional (1D) like

J Mater Sci: Mater Electron

nanowires or nanorods, as well as two dimensional (2D) as nanowalls or nanoplates [11, 12]. Among them, 1D metal oxide semiconductors (such as nanorod, nanofiber, and nanotube) are mostly interested for catalytic purposes. These nanomaterials offer a large ratio of surface/volume, enhanced electron transport, and ability for production of more reactive sites on the top of surface [13]. Nanorodstructured ZnO presents straight pathway for transportation of excited electrons, thus decreasing down the recombinati