A clean low-temperature ZnO deposition method for multipurpose applications

Abstract

Zinc oxide (ZnO) was dissolved in an aqueous solution of ammonia and hydrogen peroxide. According to XRD characterization, this precursor solution yielded crystalline zincoxide after evaporation and thermal treatment at 90 °C for 2 h. The processability of this precursor solution allowed for ZnO deposition on cellulose paper, which is an example of a thermolabile substrate. Cellulose filter paper that was impregnated with this solution and subsequently thermally treated at 90 °C for 2 h had nanostructured crystalline ZnO well adhered to its surface. This composite material was characterized by XRD and scanning electron microscopy (SEM). The described precursor solution also assisted in the preparation of ZnO porous layers for dye-sensitized solar cells (DSC). For this purpose, it was mixed with ZnO nanopowder dispersed in ethanol. The mixture was then sprayed on transparent conductive oxide substrates. In this way porous films were obtained after heat treatment at 90 °C for 2 h. Under standard testing conditions (AM1.5G, 100 mW cm–2), a device prepared with (Bu4N)2[Ru(dcbpyH)2(NCS)2] (dcbpy = 4,4′-dicarboxy-2,2′-bipyridine) (N-719) dye and a film thickness of 5 μm exhibited 1.43 % efficiency.