One Dimensional GaN Nanostructures: Growth Kinetics and Applications

Long regarded as a matter of scientific curiosity, GaN has been continued as the most important and indispensable materials used among all other compound semiconductors and is also expected to play a critical role in future optoelectronic devices. We cover recent advances in growth and characterization of chemically synthesized quasi one dimensional GaN nanostructure in various forms, such as nanowires, nanorods, nanotubes, nanopipes, and nanotips and their complex heterostructures. We first briefly introduce the general scheme based on metal catalyzed vapour-liquid- solid growth mechanism for the synthesis of a broad range of nanostructures. The novelty of catalyst free growth of such nanostructures has also been highlighted. Complex structures, such as hierarchical and core-shell structures, are also touched upon. The electrical and optoelectronic properties depend on chemical composition, doping and other physical dimensions along with the type of growth technique being used. Size sensitive optical, electrical, thermal and mechanical properties of such nanostructure have strong influence on device properties. We intend to review these properties in case of GaN nanostructures. We will also explore the methods to assemble and integrate such nanostructures into large-scale functional devices for varied practical applications. Room-temperature high-performance electrical and optical devices will then be discussed at the single as well as assembly of nanowire. A section will be dedicated for detailed discussion on recent development of GaN nanostructures, including, light emitting diode, photovoltaic, photocatalysis, biosensor, gas and chemical sensor, and nanochannel. Technical challenges and scientific questions for the widespread use of GaN nanostructures, so relevant issues will also be briefly addressed.