Zinc Oxide Nanowire Films: Solution Growth, Defect States and Electrical Conductivity - Advanced Materials for Agriculture, Food and Environmental Safety - page 451

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Zinc Oxide Nanowire Films: Solution
Growth, Defect States and Electrical
Conductivity
Ajay Kushwaha* and M. Aslam
Department of Physics, Indian Institute of Technology Bombay,
Powai, Mumbai, India
Abstract
Zinc oxide (ZnO) nanostructures of er the most promising platform for fabri-
cation of various optoelectronic devices. Insulating and nonmagnetic pristine
ZnO becomes highly electrically conductive and magnetic due to the presence of
the large concentration of impurities and defects. High surface area in nanowire
i lms enhances the defect density and alters optical and electrical properties. In
this chapter, we initially review the solution growth processes to fabricate ZnO
nanowire i lms. h en, theoretically proposed and experimentally observed defect
states and their origin are discussed. h e role of defect states which unintention-
ally dope the ZnO is reviewed and the source of n-type and p-type conductivities
is looked into. Further, we discuss the inl uence of defect states on the electri-
cal conductivity and photosensitivity of zinc oxide nanowire i lms. h e chapter
concludes with a brief introduction about ZnO nanowires-based green energy
conversion devices.
Keywords: Zinc oxide, nanowire, photoluminescence, defect states, surface
defects, oxygen vacancies, electrical transport, green energy conversion
16.1 Introduction
Zinc oxide is a binary compound semiconductor which belongs to II-VI
group and has cubic zinc-blende or hexagonal wurtzite crystal structure