Functional properties of amine-passivated ZnO nanostructures and dye-sensitized solar cell characteristics

Monodispersed ZnO nanosheets have been synthesized by a facile wet chemical approach using hexamethylenetetramine (HMTA) as an organic ligand. The synthesized samples were characterized by X-ray diffraction, field emission scanning and transmission electron microscopy, UV–visible absorption, photoluminescence spectrophotometry and X-ray photoelectron spectroscopy surface analysis. The role of HMTA concentration on the formation and functional properties of ZnO nanostructure were investigated. Particle agglomeration was restricted and the nanosheet size was limited to 20 nm by passivation of the amine molecule. The 0.05 M HMTA-capped ZnO nanosheets yield a high near band edge luminescence intensity. Dye sensitized solar cells were fabricated using synthesized ZnO nanostructures and a maximum efficiency of 3.21% was achieved.

► Shape controlled and monodispersed synthesis of ZnO nanosheets.
► HMTA act as an efficient surface passivating agent to limit the particle size.
► Functional properties of ZnO nanostructures have been enhanced by amine molecules.
► ZnO based DSSC exhibits the efficiency of 3.21% using N719 sensitizer.