@article {Pimentel2017,
	title = {{3D ZnO/Ag surface-enhanced Raman scattering on disposable and flexible cardboard platforms}},
	journal = {Materials},
	volume = {10},
	number = {12},
	year = {2017},
	note = {n/a},
	abstract = {<p>{\textcopyright} 2017 by the authors. In the present study, zinc oxide (ZnO) nanorods (NRs) with a hexagonal structure have been synthesized via a hydrothermal method assisted by microwave radiation, using specialized cardboard materials as substrates. Cardboard-type substrates are cost-efficient and robust paper-based platforms that can be integrated into several opto-electronic applications for medical diagnostics, analysis and/or quality control devices. This class of substrates also enables highly-sensitive Raman molecular detection, amiable to several different operational environments and target surfaces. The structural characterization of the ZnO NR arrays has been carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM) and optical measurements. The effects of the synthesis time (5-30 min) and temperature (70-130 {\textdegree}C) of the ZnO NR arrays decorated with silver nanoparticles (AgNPs) have been investigated in view of their application for surface-enhanced Raman scattering (SERS) molecular detection. The size and density of the ZnO NRs, as well as those of the AgNPs, are shown to play a central role in the final SERS response. A Raman enhancement factor of 7 {\texttimes} 105was obtained using rhodamine 6 G (RG6) as the test analyte; a ZnO NR array was produced for only 5 min at 70 {\textdegree}C. This condition presents higher ZnO NR and AgNP densities, thereby increasing the total number of plasmonic "hot-spots", their volume coverage and the number of analyte molecules that are subject to enhanced sensing.</p>
},
	keywords = {Ag nanoparticles, Cardboard substrates, Microwave synthesis, SERS, ZnO nanorods},
	issn = {19961944},
	doi = {10.3390/ma10121351},
	author = {Pimentel, A. and Ara{\'u}jo, A and Coelho, B.J. and Nunes, D. and Oliveira, M.J. and Mendes, MJ and {\'A}guas, H. and Martins, R. and Fortunato, E.}
}
