Synthesis, Dopant Study and Device Fabrication of Zinc Oxide Nanostructures: Mini Review

The advantageous crystal structure properties along with the ease growth of one-dimensional (1-D) zinc oxide (ZnO) nanostructures define the material to possess wide technological applications. The ultimate goal of this review article is to provide an overview of research activities prevailing on ZnO nanostructures from the basic synthesis technique to world-wide scientific and industrial applications. The article covers the recent progress, growth of ZnO nanostructures with unique and dimensionality confined morphology through surfactant-assisted simple chemical precipitation methods and through newly emerging self assembly techniques. Much emphasis is showered on the growth of nanostructures with controlled size and shape, synthesized by means of precipitation of a solid phase from solution. It also highlights the superior physio-chemical properties including structural, optical, electrical, and magnetic properties with the addition and substitution of dopant atoms. The optical properties including UV absorption and luminescence studies are rigorously probed for samples in the form of nanostructures and thin film prepared by various methods and doped with different impurities. The review further outlines the implementation of material properties in opto-electronic device applications and their commercial availability. This article extensively explores the achievements, research prospects, limitations and updates upcoming in n-type and p-type ZnO nanostructures. Additionally, we devote our attention to the study of native defects, origin of surface defects, defect emissions and their role in producing unintentional n-type ZnO. Finally, the review concludes with the homo- and hetero-type junction formation, device characterization and the open challenges to stabilize the device construction. This article also includes the research work carried out in our nanomaterials laboratory on ZnO preparation (both powder and thin film) and their characterizations and property studies will be presented briefly. We trust this review will be beneficial to expand the practical applications and offer some inspirations to the researchers in the fields of engineering, biomedicine, and materials science.