Length versus Radius Relationship for ZnO Nanowires Grown via Vapor Phase Transport

Saunders, Ruth B.; Garry, Seamus; Byrne, Daragh; Henry, M.O.; McGlynn, Enda

doi:10.1021/cg3009738

Cited by 11 publications

(10 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is consistent with previous work in our group that found that the growth process is quenched when the residual O 2 in the tube is sufficiently depleted by a longer Ar flow during the initial steps of the CTR-VPT process, e.g. after about 15-30 minutes Ar flow[29,30].…”

supporting

confidence: 93%

Growth of 18 O isotopically enriched ZnO nanorods by two novel VPT methods

Gray

Trefflich

Röder

et al. 2017

Journal of Crystal Growth

Self Cite

View full text Add to dashboard Cite

We have developed two novel vapour phase transport methods to grow ZnO nanorod arrays isotopically enriched with 18 O. Firstly, a three-step process used to grow natural and Zn-enriched ZnO nanorods has been further modified, by replacing the atmospheric O 2 with enriched 18 O 2 , in order to grow 18 O-enriched ZnO nanorods using this vapour-solid method on chemical bath deposited buffer layers. In addition, 18 O-enriched ZnO nanorods were successfully grown using isotopically 18 O-enriched ZnO source powders in a vapour-liquidsolid growth method. Scanning electron microscopy studies confirmed the success of both growth methods in terms of nanorod morphology, although in the case of the vapour-liquidsolid samples, the nanorods' c-axes were not vertically aligned due to the use of a non

show abstract

supporting

confidence: 93%

Growth of 18 O isotopically enriched ZnO nanorods by two novel VPT methods

Gray

Trefflich

Röder

et al. 2017

Journal of Crystal Growth

Self Cite

View full text Add to dashboard Cite

show abstract

“…The absorbed and reabsorbed atoms can easily diffuse after obtaining enough energy from the incident electrons, leading to the atomic movements shown in Figs 2 and 3. Since the estimated diffusion length of Zn atoms on ZnO sidewalls is over 100 nm34, the knocked atoms can migrate on the surface and act as one of the main sources of the growth. These sputtered atoms can be easily absorbed on the polar surface (0001), which possesses a large surface free energy3536, resulting in the layer-by-layer growth of ZnO nanopillars along the polar [0001] direction.…”

Section: Discussionmentioning

confidence: 99%

Direct Observation of the Layer-by-Layer Growth of ZnO Nanopillar by In situ High Resolution Transmission Electron Microscopy

Cheng

Deng

et al. 2017

Sci Rep

View full text Add to dashboard Cite

Catalyst-free methods are important for the fabrication of pure nanowires (NWs). However, the growth mechanism remains elusive due to the lack of crucial information on the growth dynamics at atomic level. Here, the noncatalytic growth process of ZnO NWs is studied through in situ high resolution transmission electron microscopy. We observe the layer-by-layer growth of ZnO nanopillars along the polar [0001] direction under electron beam irradiation, while no growth is observed along the radial directions, indicating an anisotropic growth mechanism. The source atoms are mainly from the electron beam induced damage of the sample and the growth is assisted by subsequent absorption and then diffusion of atoms along the side surface to the top (0002) surface. The different binding energy on different ZnO surface is the main origin for the anisotropic growth. Additionally, the coalescence of ZnO nanocrystals related to the nucleation stage is uncovered to realize through the rotational motions and recrystallization. Our in situ results provide atomic-level detailed information about the dynamic growth and coalescence processes in the noncatalytic synthesis of ZnO NW and are helpful for understanding the vapor-solid mechanism of catalyst-free NW growth.

show abstract

“…CVD techniques are particularly versatile in order to tailor the deposition of NWs or other types of nanostructures, like nanobelts, nanosprings, nanorings, nanoribbons, nanosheets, nanotetrapods, etc. [52][53][54][55][56][57][58][59] Vapor-liquid-solid (VLS) and vaporsolid (VS) processes are usually performed in a tubular furnace with a temperature gradient between the precursor and the substrate, allowing condensation and nucleation of nanostructures downstream the gas flow. [50] CVD generally involves the use of a precursor material (typically metal or metal oxide [51] ) that is evaporated and transported by a carrier gas toward a substrate, where it nucleates, sometimes in presence of a catalyst.…”

Section: Synthesis Of Metal Oxide Nanowires and Nanorodsmentioning

confidence: 99%

Recent Developments and Perspectives for Memristive Devices Based on Metal Oxide Nanowires

Milano

Porro

Valov

et al. 2019

Adv Elect Materials

116

View full text Add to dashboard Cite

Memristive devices are considered one of the most promising candidates to overcome technological limitations for realizing next‐generation memories, logic applications, and neuromorphic systems in the modern nanoelectronics and information technology. Despite the continuous efforts, understanding the resistive switching mechanism underlying memristive/neuromorphic behavior still represents a challenge. Metal oxide nanowire‐based memristors appear suitable model systems for a deeper understanding of the involved physical/chemical phenomena due the possibility for localizing and investigating the switching mechanism. In practical aspects, nanowire‐based devices can be grown using a bottom‐up approach, thus being considered reliable candidates for going beyond the current scaling limitations of the top‐down approach by the standard lithography. In addition, taking into advantage of the high surface‐to‐volume ratio of these nanostructures, new device functionalities can be achieved by exploiting surface effects. In the literature, a variety of nanowire‐based devices such as single nanowires, nanowire arrays, and networks are reported to exhibit memristive behavior, explained by different switching mechanisms. This work provides a comparative review and a comprehensive analysis of device performances and physical phenomena responsible for memristive and neuromorphic behavior in such nanostructures. The analysis of the state‐of‐art of memristor devices based on nanowires and nanorods represent a milestone toward the development of nanowire‐based artificial neural networks.

show abstract

Length versus Radius Relationship for ZnO Nanowires Grown via Vapor Phase Transport

Cited by 11 publications

References 24 publications

Growth of 18 O isotopically enriched ZnO nanorods by two novel VPT methods

Growth of 18 O isotopically enriched ZnO nanorods by two novel VPT methods

Direct Observation of the Layer-by-Layer Growth of ZnO Nanopillar by In situ High Resolution Transmission Electron Microscopy

Recent Developments and Perspectives for Memristive Devices Based on Metal Oxide Nanowires

Contact Info

Product

Resources

About