Optical properties of two-dimensional ZnO nanosheets formed by hot-water treatment of Zn foils

Two-dimensional ZnO nanosheets were formed on metallic Zn foils after hot-water treatment at 90 °C for 4, 8, 12 and 24 h. The photoluminescence spectra of the as-formed ZnO nanosheets exhibit near band edge UV and green emissions; indicating their good crystallinity with presence of oxygen related defects. Raman scattering of the ZnO nanosheets indicated ZnO crystals of high quality were obtained, which was supported by high resolution transmission electron microscope (HR-TEM) results. This low-temperature formation of interconnected two-dimensional ZnO nanosheets with high quality would enable the utilization of substrates with low-thermal stability for optoelectronics applications.