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.

Janus particle arrays with multiple structural controlling abilities synthesized by seed-directed deposition

“…It is found that Ag nanoparticles are indeed unable to grow on the pristine surface of the PS spheres because of their smooth surfaces and chemical inertness, giving rise to failure to get Janus particle arrays. [33][34][35] This is similar to previous studies about electrochemical deposition of ZnO with the bare MCC template. [33][34][35] ZnO components are preferentially deposited on the substrate instead of on the surface of the PS templates, leading to the formation of porous ZnO nanostructures.…”

“…[33][34][35] This is similar to previous studies about electrochemical deposition of ZnO with the bare MCC template. [33][34][35] ZnO components are preferentially deposited on the substrate instead of on the surface of the PS templates, leading to the formation of porous ZnO nanostructures. [33][34][35] Therefore, a thin layer of gold film is of prime importance in fabricating the Janus particle arrays.…”

Seeded Growth Route to Noble Calcium Carbonate Nanocrystal

“…Thus, the uniform crystal morphology obtained in this study most likely could be due to the existence of thermal equilibrium conditions of the colloidal particle. An observation somewhat analogous to that reported in the case of metal oxide nanoparticle synthesis by other researchers [ 20 – 21 ].This high degree of morphological control demonstrates that surfactants are capable of strongly interacting with the CaCO 3 surface and affecting nucleation and growth. Precipitation reaction is important to control the nucleation of particles.…”

Aqueous Phase Synthesis and Enhanced Field Emission Properties of ZnO-Sulfide Heterojunction Nanowires

“…Figure 6a illustrates the UPS spectra of the as-prepared ZnO, ZnO-CdS, ZnO-ZnS, and ZnO-Ag 2 S NWAs. Due to the strong surface charge effect, the work function of ZnO is measured to be around 4.11 eV which is lower than the reported value of ~5.38 eV 18 25 26 27 28 . Based on the highest occupied molecular orbitals (HOMOs), the maximum energy level of valence band ( E v ) of the as-prepared ZnO has been deduced to be 7.55 eV ( ).…”