Preparation and Optoelectronic Applications of Silicon Nanowire Arrays

Recent years, silicon nanowire arrays have aroused extensive attention among scientists and engineers due to their unique characteristics such as excellent antireflection in both wide wavelength range and wide incidence angle and their great potentials in the field of optoelectronics. This paper reviews the latest research progress in preparation of silicon nanowire arrays and their optoelectronic applications. The preparation methods that have been verified are classified mainly into two categories, i.e., "bottom-up "and" top-down", including template-assisted chemical vapor deposition, chemical vapor deposition combined with Langmuir-Blodgett technology and metal-catalyzed chemical etching. The third method is at the present time the most frequently used as well as the simplest one, and is discussed in detail in respect of the etching steps, mechanism and controlling parameters. As for the optoelectronic applications of silicon nanowire arrays, this review mainly describes those in photodetectors, conventional solar cells, photoelectrochemical solar cells, photocatalytic water splitting, and photocatalytic degradation of organic pollutants. Finally, an outlook is made about how to improve the photoelectrical conversion efficiency and avoid the corrosion of silicon nanowire arrays, which indicates that surface modification and resulting properties may be a future research direction for silicon nanowire arrays research.