TY - JOUR
T1 - Alignment, morphology and defect control of vertically aligned ZnO nanorod array
T2 - Competition between "surfactant" and "stabilizer" roles of the amine species and its photocatalytic properties
AU - Ranjith, Kugalur Shanmugam
AU - Pandian, Ramanathaswamy
AU - McGlynn, Enda
AU - Rajendra Kumar, Ramasamy Thangavelu
PY - 2014/6/4
Y1 - 2014/6/4
N2 - We demonstrate effective control of the morphology, defect content and vertical alignment of ZnO nanorod (NR) arrays grown by a solution method by simply varying the hexamine concentration during growth. We show that the amine acts both as a growth 'stabilizer' and 'surfactant' and controls both Zn release for ZnO formation and caps non-polar planes, respectively. Competition between these 'stabilizer' and 'surfactant' roles facilitates morphology, alignment and defect content control of 1D ZnO NR arrays. Well aligned, prismatic, defect (Zn interstitial) controlled ZnO NR arrays grown with a 1M amine concentration show higher photocatalytic degradation of Methylene Blue dye solutions under UV irradiation. Shallow donor zinc interstitials readily supply electrons which may increase the space charge near the nano-catalyst surface. The increased band bending associated with the interfacial electric field in the space charge region may then better facilitate the separation of photogenerated carriers and thus enhance the photocatalytic performance. Understanding the role of amine in the solution growth of 1D ZnO NR arrays holds great promise for tailoring ZnO NR functionalities for various potential applications.
AB - We demonstrate effective control of the morphology, defect content and vertical alignment of ZnO nanorod (NR) arrays grown by a solution method by simply varying the hexamine concentration during growth. We show that the amine acts both as a growth 'stabilizer' and 'surfactant' and controls both Zn release for ZnO formation and caps non-polar planes, respectively. Competition between these 'stabilizer' and 'surfactant' roles facilitates morphology, alignment and defect content control of 1D ZnO NR arrays. Well aligned, prismatic, defect (Zn interstitial) controlled ZnO NR arrays grown with a 1M amine concentration show higher photocatalytic degradation of Methylene Blue dye solutions under UV irradiation. Shallow donor zinc interstitials readily supply electrons which may increase the space charge near the nano-catalyst surface. The increased band bending associated with the interfacial electric field in the space charge region may then better facilitate the separation of photogenerated carriers and thus enhance the photocatalytic performance. Understanding the role of amine in the solution growth of 1D ZnO NR arrays holds great promise for tailoring ZnO NR functionalities for various potential applications.
UR - http://www.scopus.com/inward/record.url?scp=84901951663&partnerID=8YFLogxK
U2 - 10.1021/cg5001792
DO - 10.1021/cg5001792
M3 - Article
AN - SCOPUS:84901951663
SN - 1528-7483
VL - 14
SP - 2873
EP - 2879
JO - Crystal Growth and Design
JF - Crystal Growth and Design
IS - 6
ER -