This is clearly demonstrated in the case of high-density Au nanoparticles, as shown in Figure 8a (iv). On the other hand, when the distance between the Au nanoparticles is significantly larger than the drifted Zn length, as in the low-density case, the growth process can also result in the formation of NW-nanofin hybrid structures with prolonged synthesis time (as depicted in Figure 8b (iv)). Conclusions In summary, controlled growth of various ZnO nanostructures, including nanowires (NWs), nanowalls (NWLs), and hybrid nanowire-nanowall, was demonstrated through careful control

of key experimental parameters, including Au seed thickness, synthesis temperature, and time, via a Akt inhibitor combination of catalytic-assisted and non-catalytic-assisted VLS processes. A combination of nanomaterial characterization techniques revealed that highly selleck products crystalline wurtzite nanostructures were produced. Experimental work presented here suggests that the nanomaterial synthesis temperature effectively controlled the Zn cluster drift phenomenon, responsible for

the formation of the various studied ZnO nanostructures. NWs were found to grow at comparatively lower temperatures, and the overall NW density was effectively controlled through the Au seed film thickness. High-density Au clusters and high growth temperatures resulted in NWLs and hybrid NW-NWL formation. The formation of such structures check details was found also to depend on the synthesis time. These results offer a new prospective towards the

development of applications that require various predefined ZnO nanostructures on [0001]-oriented SiC as well as other similar compound substrates, including GaN, AlN, and GaN-on-Si substrates targeting future high-performance nanodevices. Acknowledgements The authors gratefully acknowledge the support of the MIND (Multifunctional and Integrated Piezoelectric devices) European Network of Excellence (NoE 515757–2 of the 6th Framework Program) and the Region Centre who supports the CEZnO project (Convertisseur Electromécanique à base de nanofils ZnO, 2011 many to 2014). The authors also thank Drs. D. Valente and V. Grimal for their technical assistance in material characterization experiments. References 1. Ng HT, Han J, Yamada T, Nguyen P, Chen YP, Meyyappan M: Single crystal nanowire vertical surround-gate field-effect transistor. Nano Lett 2004,4(7):1247. 10.1021/nl049461zCrossRef 2. Wang X, Wang X, Zhou J, Song J, Liu J, Xu N, Wang ZL: Piezoelectric field effect transistor and nanoforce sensor based on a single ZnO nanowire. Nano Lett 2006,6(12):2768. 10.1021/nl061802gCrossRef 3. Wang XD, Zhou J, Lao CS, Song JH, Xu NS, Wang ZL: In situ field emission of density-controlled ZnO nanowire arrays. Adv Mater 2007,19(12):1627. 10.1002/adma.200602467CrossRef 4. Zhang Q, Dandeneau CS, Zhou X, Cao G: ZnO nanostructures for dye-sensitized solar cells. Adv Mater 2009,21(41):4087. 10.1002/adma.