Improved Low-Temperature Aqueous Synthesis of ZnO Nanorods and Their Use in SERS Detection of 4-ABT and RDX

作     者：Marcia del R.Balaguera-Gelves Oscar J.Perales-Pérez Surinder P.Singh José A.Jiménez Joaquín A.Aparicio-Bolanos Samuel P.Hernández-Rivera 

作者机构：Department of ChemistryUniversity of Puerto Rico-MayaguezMayagüezPuerto Rico Department of Engineering Science and MaterialsUniversity of Puerto Rico-MayaguezMayagüezPuerto Rico Department of ChemistryUniversity of North FloridaJacksonvilleUSA Department of Chemistry and PhysicsUniversity of Puerto Rico-PoncePoncePuerto Rico 

出 版 物：《Materials Sciences and Applications》 (材料科学与应用期刊（英文）)

年 卷 期：2013年第4卷第1期

页      面：29-38页

学科分类：07[理学] 0703[理学-化学] 

基　　金：Support from the U.S.Department of Homeland Security under Award Number 2008-ST-061-ED0001 is also ac-knowledged This contribution was supported by the U.S.Depart-ment of Defense,Proposal Number:58949-PH-REP,Agreement Number:W911NF-11-1-0152 

主　　题：ZnO Nanorods Sputtering SERS 4-ABT RDX 

摘      要：The growth-controlled synthesis of zinc oxide nanorods (ZnO NR) in the aqueous phase has been investigated. The rods were grown on ZnO films previously deposited onto Si(100) and indium tin oxide (ITO) substrates by RF magnetron sputtering. The formation of the rods took place in the presence of hexamethylenetetramine (HMT) as habit-control reagent. The grains in the base ZnO film acted as seeds that promoted the longitudinal growth of the oxide. As-synthesized base films and rods were characterized by X-ray diffraction, scanning electron microscopy (SEM), field emission SEM, optical absorption and photoluminescence spectroscopy techniques. Subsequently, a wet chemistry procedure was performed to achieve ZnO NR growth. This methodology was conducive to the formation of rods of a relatively narrow distribution of diameters (60 - 70 nm) with lengths in the 1 - 3 μm range. Photoluminescence spectra were characterized by a dominant near-band-edge (NBE) peak followed by a green luminescence (GL) broad band, indicative of higher oxygen vacancy concentration in the ZnO NR grown on ZnO/ITO in comparison with those grown on ZnO/Si(100). A UV process was used for coating the ZnO NR with gold (Au). Au coating on ZnO NR was used to evaluate the detection capability by SERS of different analytes such as: 4-aminobenzenethiol (4-ABT) and 1,3,5-trinitroperhydro-1,3,5- triazine (RDX) at low levels. A strong SERS Raman spectrum was observed for 4-ABT. A limit of detection (LOD) of 1 × 10-8M for 4-ABT was achieved corresponding to a minimum of 5.4 × 105molecules detected under the experimental conditions at excitation wavelength of 785 nm with a sensitivity of the ZnO NR in the range of 1.1 × 10-16g under the laser spot.