Controlled growth of 1D-ZnO nanotubes using one-step hot plate technique for CZTS heterojunction solar cells

Abstract Present work reports a simple, rapid, one-step hot plate technique for systematic growth transformation of highly oriented ZnO nanorods (ZNRs) into ZnO nanotubes (ZNTs). The controlled growth of ZnO nanostructures (nanorods and nanotubes) was achieved at low temperature (90 °C) in a short time (1hr) in a sealed weighing bottle (100 ml). It is observed that as the Zinc precursor concentration increases, a vertically grown ZnR morphology evolves into ZNT. The crystal structure of as-grown ZnO nanostructures, surface morphology, phase, and optical energy gap were respectively characterized by XRD, FESEM, Raman, XPS, CL and UV–Vis spectroscopy. Grown nanostructures are further explored for their application in CZTS based heterojunction photovoltaics.