RuO2 nanoparticles by a novel green process via Aspalathus linearis natural extract & their water splitting response

This contribution reports on the biosynthesis of quasi-monodisperse rutile Ruthenium (IV) oxide nanoparticles with an average diameter of 2.15 nm using Aspalathus linearis natural extract as a chelating agent as well as a capping compound. Their morphological, structural and optical properties were investigated using various complementary surface/interface characterization techniques. This includes transmission electron microscopy, selective area electron diffraction. Their optical band gap was found to be about 2.1 eV. Loaded onto a p-type Cu2O thin film, the nano-scaled RuO2-Cu2O tandem exhibits an effective water photo-splitting response in the solar spectrum.