Epitaxial growth of successive CdSe ultrathin films and quantum dot layers on TiO2 nanorod arrays for photo-electrochemical cells

Abstract

In this work, successive cadmium selenide (CdSe) ultrathin films and quantum dot layers were successfully deposited on TiO₂ nanorod arrays by the electrochemical atomic layer epitaxy method (ECALE). The underpotential deposition (UPD) processes of the successive CdSe films and quantum dot layers were recorded in detail. The photo-electrochemical properties of the CdSe coated TiO₂ nanorod array electrodes were also investigated, and the maximum current density reached 14.6 mA cm⁻² under one sun (AM 1.5G, 100 mW cm⁻²). Using the ECALE method to grow a buffer layer between quantum dots and their supporting material will be useful for other energy-providing materials.