Temperature-controlled nanomosaics of AuCu bimetallic structure towards smart light management

Abstract Gold–copper nanostructures are promising in solar-driven processes because of their optical, photocatalytic and photoelectrochemical properties, especially those which result from the synergy between two metals. Increasing interest internal structure, such as composition or distribution Au Cu well size shape nanoparticles, have developed to define physicochemical properties. In this work, we present influence thermal treatment temperature ranges 100 600 °C on formation process bimetallic AuCu structures materials were placed nanostructured titanium foil substrates that fabricated using electrochemical anodisation chemical etching. Thin layers mixture, Cu, sputtered obtained Ti nanodimples. The then annealed a rapid annealing furnace an air atmosphere. Thermal strongly affected morphology optical properties materials. NPs formed at 400 dimples. material exhibits absorption visible light range c.a. 700 nm. characterisation nature samples was determined X-ray photoelectron spectroscopy. addition, diffraction Raman spectroscopy defined crystallinity. Based studies carried out with use linear voltammetry 0.1 M NaOH, it is possible distinguish types interactions photogenerated charge accumulation electron–hole pair separation. A 10AuCu electrode 300 achieved highest current registered under illumination − 0.17 V vs. Ag/AgCl/0.1 KCl. value 11 times higher than for non-annealed structure.