Template Deformation‐Tailored ZnO Nanorod/Nanowire Arrays: Full Growth Control and Optimization of Field‐Emission

Abstract

Here, a facile and effective route toward full control of vertical ZnO nanorod (NR)/nanowire (NW) arrays in centimeter‐scale areas and considerable improvement of field‐emission (FE) performance is reported. Controlled deformation of colloidal crystal monolayer templates is introduced by heating near glass‐transition temperature. The NR/NW density, uniformity, and tapering were all adjusted through selection of template size and deformation, and electrolyte composition. In line with the adjustments, the field‐emission performance of the arrays is significantly improved. A low turn‐on electric field of 1.8 V µm−1, a field‐enhancement factor of up to 5 750, and an emitting current density of up to 2.5 mA cm−2 were obtained. These improved parameters would benefit their potential application in cold‐cathode‐based electronics.

Arrays of nanorods composed of ZnO nanodots exhibiting enhanced UV emission and stability

“…Nanorod (NR) arrays of many different nanomaterials have been shown to have significant applications in light emission devices, 1 biosensors, 2 solar cells, 3,4 piezoelectric generators, 5,6 photocatalysis, 7,8 field emission devices, 9 etc. -reflecting their advanced functional properties and the feasibility of their incorporation within nanodevices.…”

One-dimensional ZnO nanostructures: Solution growth and functional properties

“…These spheres are commercially available with well-controlled monodisperse sizes. The hexagonally close-packed structure can be used as a mask, and the feature size is tunable by using spheres of different sizes and also by post-heat treatment [296]. When heated, the spheres deform and therefore the gaps between them shrink [297].…”

Design and tailoring of patterned ZnO nanostructures for energy conversion applications

“…Several strategies have been proposed to fabricate highly ordered ZnO NAs, such as nanosphere lithography (NSL) [64][65][66][67][68], electron beam lithography (EBL) [69][70][71][72], optical lithography (OL), and laser interference lithography (LIL) techniques [73][74][75][76][77][78][79][80]. Among these, self-assembled NSL is a simple and economical technique, which employs twodimensional (2D) self-assembled nanometer-sized polystyrene spheres as lithography masks to fabricate patterned arrays [64].…”

“…The conventional NSL required high-temperature post-treatment and had high requirement on the substrate flatness and hydrophobicity. On the other hand, the fabrication of defect-free and period-adjustable ZnO NAs was difficult, owing to the introduction of metal catalyst dots and the inhomogeneous distribution of polystyrene nanospheres [67]. Recently, patterned ZnO NAs were fabricated by an NSL technique that patterns a thickness variation on a polymethyl methacrylate layer [68].…”