Synthesis of Monodispersedly Sized ZnO Nanowires from Randomly Sized Seeds

Abstract

We demonstrate the facile, rational synthesis of monodispersedly sized zinc oxide (ZnO) nanowires from randomly sized seeds by hydrothermal growth. Uniformly shaped nanowire tips constructed in ammonia-dominated alkaline conditions serve as a foundation for the subsequent formation of the monodisperse nanowires. By precisely controlling the sharp tip formation and the nucleation, our method substantially narrows the distribution of ZnO nanowire diameters from σ = 13.5 nm down to σ = 1.3 nm and controls their diameter by a completely bottom-up method, even initiating from randomly sized seeds. The proposed concept of sharp tip based monodisperse nanowires growth can be applied to the growth of diverse metal oxide nanowires and thus paves the way for bottom-up grown metal oxide nanowires-integrated nanodevices with a reliable performance.

Face-selective tungstate ions drive zinc oxide nanowire growth direction and dopant incorporation

“…To understand the contribution of WO 4 2− ions for the nucleation phenomenon, next we examine the Zn precursor concentration dependence on ZnO nanowire growth with various C W . Previous our study demonstrated that there exist two threshold concentrations corresponding to the critical concentrations for nucleation on (0001) plane and 10 10 ð Þ plane [22][23][24] . By evaluating the shifts of critical concentrations with varying C W , the influence of WO 4 2− ions for the nucleation events on ZnO crystal planes can be identified.…”

“…In principle, there are two possible approaches for modulating the dopant incorporation, i.e., a control of W precursor concentration and a control of dopant adsorption on nanowire surface. On the other hand, the morphology can be manipulated by controlling C Zn according to the critical concentration for nucleation on ZnO crystal planes, which is so-called as "concentration window" principle [22][23][24] . However, as shown in Fig.…”

“…Therefore, most of previous researches have been devoted to establish predictable models and strategies for controlling the morphology of nanomaterials. As for the hydrothermally synthesized zinc oxide (ZnO) nanowires, the strategies based on the electrostatic interaction between metal ions and crystals 19 , the organic ligand based surface capping 20 , the ligandexchange effect 21 , and the difference in critical nucleation concentrations on crystal planes so-called "concentration window" [22][23][24] have been demonstrated and successfully manipulated the nanowire morphology.…”

ZnO Metal Oxide Semiconductor in Surface Acoustic Wave Sensors: A Review

“…ZnO has also attracted attention for its low cost, ease of preparation, very good chemical stability, suitability to doping, non-toxicity, and ease of processing, for example in the form of thin films [ 84 , 128 ]. This is a material that can be easily synthesized in various types of nanostructures, such as nanorods ( Figure 2 a) [ 122 ], nanosheets ( Figure 2 b) [ 132 ], nanotubes ( Figure 2 c) [ 133 ], nanoflowers ( Figure 2 d) [ 1 ], microspheres ( Figure 2 e) [ 134 ], nanoplates ( Figure 2 f) [ 113 ], nanoflakes ( Figure 2 g) [ 135 ], nanowires ( Figure 2 h) [ 136 ], and nanofibers ( Figure 2 i) [ 137 ]. These types of microstructures ensure a large specific surface area and allow the penetration of gas molecules into the volume of the material, which is a great advantage for RT detection with SAW sensors [ 128 , 138 , 139 , 140 , 141 ].…”

“… Scanning Electron Microscope (SEM) images for different types of morphologies obtained for ZnO: nanorods ( a ) [ 122 ], nanosheets ( b ) [ 132 ], nanotubes ( c ) [ 133 ], nanoflowers ( d ) [ 1 ], microspheres ( e ) [ 134 ], nanoplates ( f ) [ 113 ], nanoflakes ( g ) [ 135 ], nanowires ( h ) [ 136 ], and nanofibers ( i ) [ 137 ]. Reproduced (2020) with permission from Elsevier and ACS Publications.…”