Trapping and Recombination Properties of the Acceptor-like VZn-H Complex Defect in ZnO

• Published in: Journal of physical chemistry. C Vol. 117; no. 8; pp. 4299 - 4303
• Main Authors: Senthilkumar, K, Subramanian, M, Ebisu, H, Tanemura, M, Fujita, Y
• Format: Journal Article
• Language: English
• Published: Columbus, OH American Chemical Society 28.02.2013
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Nanocrystals and nanoparticles; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; Complex defect; Raman spectra; Doping; Photoluminescence; Nanoparticles; Charge carrier trapping; Ultraviolet radiation; Hydrogen bonds; Hydrogen additions; Vibrational modes; Illumination; Zinc oxide; Electron paramagnetic resonance; Localized modes
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp312209c

We report trapping and recombination centers with an acceptor-like character VZn and their defect complex in unintentional hydrogen-doped ZnO nanoparticles using photoluminescence and electron paramagnetic resonance (EPR) techniques. Further, we demonstrate the existence of a VZn–H complex defect related to local vibrational modes (LVMs) by Raman spectroscopy. EPR measurement confirms the characteristics of an uncompensated donor and acceptor under UV illumination in addition to the existence of multiple trapping centers even when the samples are subjected to high-temperature annealing; some of the LVMs related to VZn–H complex defect still persist with less intensity due to high thermal stability. Hydrogen bonding with native defect in ZnO lattice and their charge states are found to play a crucial role in achieving the donor and acceptor characteristics.