This article reviews recent progresses in growth mechanism, synthesis, and applications of zinc oxide nano-materials (mainly focusing on one-dimensional (1D) nanomaterials). In the first part of this article, we brieflyintroduce the importance, the synthesis methods and growth mechanisms, the properties and applications ofZnO 1D nanomaterials. In the second part of this article, the growth mechanisms of ZnO 1D nanomaterialswill be discussed in detail in the framework of vapor-liquid-solid (VLS), vapor-solid (VS), and aqueous solutiongrowth (ASG) approaches. Both qualitative and quantitative information will be provided to show how acontrolled synthesis of ZnO 1D nanomaterials can be achieved. In the third part of this article, we presentrecent progresses in our group for the synthesis of ZnO 1D nanomaterials, and the results from other groupswill only be mentioned briefly. Especially, experiment designing according to theories will be elaborated todemonstrate the concept of controlled synthesis. In the fourth part of this article, the properties and potentialapplications of ZnO 1D nanomaterials will be treated. Finally, a summary part will be presented in the fifthsection. The future trend of research for ZnO 49551
1D nanomaterials will be pointed out and key issues to be solvedwill be proposed.KEY WORDS: Zinc Oxide; One-dimensional; Nanomaterials; Controlled synthesis 1. IntroductionZnO, as an important wide bandgap (3.37 eV at0 K) semiconducting material, has been one of thehottest research targets and attracted worldwide at-tention in materials science, physics, chemistry, andindustry fields[1]. ZnO one-dimensional (1D) nanoma-terials have stimulated much research zeal in the pastdecade. So far, hundreds of papers treating issues re-lated to ZnO nanomaterials have been published oninternational journals, and this number keeps increas-ing rapidly day by day. One of the reasons for the popularity of ZnO 1D nanomaterials is many impor-tant physical and chemical properties and numerouspotential applications of this kind of materials[2–8].Some of the important properties and applications ofZnO include: (1) Wide bandgap. The bandgap ofZnO is similar to that of GaN and the ultravioletlaser emission from ZnO has been realized recently.(2) Large exciton binding energy (60 meV), two timeslarger than that of GaN, which stabilizes the excitonsup to room temperature. The significant outcome isthe realization of room-temperature UV lasers, whichcan not be fulfilled by other semiconducting materialsthat have previously been employed as UV lasing ma-terials, such as GaN and ZnSe. (3) Polarity of lattices due to the wurtzite structure, which has no center ofinversion symmetry. The polarity developed along thec axis makes this material inherent piezoelectric. Therecently discovered current generator on the basis
ofZnO is one of the most significant inventions by virtueof the polarity properties.Actually, ZnO is a chemically stable materialwhich does not decompose up to 1000±C in the at-mosphere, and does not react with diluted acids andbases. Therefore, ZnO 1D nanomaterials have beenused in many fields. For example, they are effec-tive gas sensors for a wide range of gases[9–12], andthey have been used as photocatalysts[13–16], fieldemitters[17–21], optoelectronic devices[22–25], and soon. Another important field that currently attractsa lot of attention is that ZnO has been used as thehost for magnetic ions to form diluted magnetic semi-conductors that have been claimed to show room-temperature ferromagnetism[26–30].As we just mentioned, ZnO possesses inherentpolar lattices. The polarity makes it a rather in-teresting material for investigating the morphologymultiplicity in nanoscale. As far as we know, ZnOis the most versatile material that has a rich fam-ily of morphologies, including (but not limited to)nanowires (nanorods), nanobelts, nanoplatelets, nan-otubes, nanocombs, nanorings, nanosprings, nanote-trapods, nanohelixes, and so on. The synthesis meth-ods for ZnO 1D nanomaterials are also well devel-oped, which can be pided mainly in the follow-ing categories[31–36]: (1) chemical vapor deposition,(2) hydrothermal chemistry, (3) template, (4) electro-chemistry, and (5) other (sonochemistry, irradiation,and so on). Though the synthetic methods are vari-ous, the growth mechanisms can be named only sev-eral. The characteristic growth mechanisms are[37–39]:(1) vapor-liquid-solid (VLS), 氧化锌纳米材料的合成英文文献和中文翻译:http://www.youerw.com/fanyi/lunwen_52568.html