TY - JOUR
T1 - Photoluminescence transient study of surface defects in ZnO nanorods grown by chemical bath deposition
AU - Crupi, Isodiana
AU - Strano, null
AU - Barbagiovanni, null
AU - Crupi, Isodiana
AU - Franzò, null
AU - Mirabella, null
PY - 2015
Y1 - 2015
N2 - Two deep level defects (2.25 and 2.03 eV) associated with oxygen vacancies (Vo) were identified in ZnO nanorods (NRs) grown by low cost chemical bath deposition. A transient behaviour in the photoluminescence (PL) intensity of the two Vo states was found to be sensitive to the ambient environment and to NR post-growth treatment. The largest transient was found in samples dried on a hot plate with a PL intensity decay time, in air only, of 23 and 80 s for the 2.25 and 2.03 eV peaks, respectively. Resistance measurements under UV exposure exhibited a transient behaviour in full agreement with the PL transient, indicating a clear role of atmospheric O2 on the surface defect states. A model for surface defect transient behaviour due to band bending with respect to the Fermi level is proposed. The results have implications for a variety of sensing and photovoltaic applications of ZnO NRs. © 2015 AIP Publishing LLC.
AB - Two deep level defects (2.25 and 2.03 eV) associated with oxygen vacancies (Vo) were identified in ZnO nanorods (NRs) grown by low cost chemical bath deposition. A transient behaviour in the photoluminescence (PL) intensity of the two Vo states was found to be sensitive to the ambient environment and to NR post-growth treatment. The largest transient was found in samples dried on a hot plate with a PL intensity decay time, in air only, of 23 and 80 s for the 2.25 and 2.03 eV peaks, respectively. Resistance measurements under UV exposure exhibited a transient behaviour in full agreement with the PL transient, indicating a clear role of atmospheric O2 on the surface defect states. A model for surface defect transient behaviour due to band bending with respect to the Fermi level is proposed. The results have implications for a variety of sensing and photovoltaic applications of ZnO NRs. © 2015 AIP Publishing LLC.
UR - http://hdl.handle.net/10447/155602
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84924204774&partnerID=40&md5=a3718a32fdbeb353ae3c30d2418bd88e
M3 - Article
VL - 106
JO - Applied Physics Letters
JF - Applied Physics Letters
SN - 0003-6951
ER -