One-dimensional (1D) nanostructures are of great interest due to the promise of enhanced properties and improved device performance such as increased efficiency in solar cells by improved charge separation. There are many means of producing 1D nanostructures including chemical synthesis, lithography, template assisted growth and gas phase reaction. While all of these have their advantages and disadvantages, growth by gas phase reaction has the benefit of low cost and scalability to be used in mass production. This work outlines several of the more common growth mechanisms which utilize gas phase reactions to produce 1D nanostructures. The similarities and differences between the different mechanisms are discussed with an emphasis on the confinement of growth to 1D.
