Published October 25, 2015 | Version v1
Journal article Metadata-only

Work function tuning and fluorescence enhancement of hydrogen annealed Ag-doped Al-rich zinc oxide nanostructures using a sol–gel process

Creators

  • 1. Energy Research Division, Daegu Gyeongbuk Institute of Science & Technology (DGIST), 50-1 Sang-Ri, Hyeonpung-Myeon, Dalseong-Gun, Daegu 711-873 (Korea, Republic of)
  • 2. School of Mechanical and Control Engineering, Handong Global University, 558 Handong-Ro, Heunghae-Eub, Buk-Ku, Pohang, Gyung-Buk 791-708 (Korea, Republic of)

Description

Effect of incorporation of Ag on the structural, optical, electrical, and fluorescence properties of sol–gel derived Al-rich zinc oxide (ZnO:Al:Ag) nanostructured films was studied. The Eg of the film slightly decreased to a minimal value with Ag doping, and was found to be about 3.65 eV for RAg/Zn = 1% from its initial value of 3.72 eV (RAg/Zn = 0%). The WF sudden increased to a maximal value of 5.12 eV with Ag doping (for RAg/Zn = 1%) from its initial value of 4.73 eV for RAg/Zn = 0% due to substitution of Ag into Zn sites until saturation was achieved (RAg/Zn = 1%). After more Ag doping, WF started to decrease and finally, reached a value of 4.81 eV for RAg/Zn = 3% because of the formation of an impurity-defect energy level below the intrinsic Fermi level of ZnO. With Ag-doping, the current increased up to RAg/Zn = 1% due to the increase in carrier density. For RAg/Zn = 3% doping, the current density started to increase due to the influence of metallic Ag. The defective peak position was blue shifted, with increased Ag-doping, from 536 nm (RAg/Zn = 1%) to 527 nm for RAg/Zn = 2% due to the sizes of the Ag+ and Zn2+ ions. The FL defective peak intensity (ID) in the green region increased with the concentration of Ag used for doping, up to RAg/Zn = 2%. The enhancement in the ID may be due to charge difference between the Zn2+ ions, caused by Ag+ ions. - Graphical abstract: The effect of incorporation of Ag doping on the structural, optical, electrical, and fluorescence properties of sol–gel derived Al-rich zinc oxide (ZnO:Al:Ag) nanostructured films was studied. By Ag-doping, the lowest Rλ is blue shifted to RAg/Zn = 2% and finally red shifted for RAg/Zn = 3% due to variation of optical thickness of the film. The Eg of the film slightly decreased to a minimal value with Ag doping, and was found to be about 3.65 eV for RAg/Zn = 1% from its initial value of 3.72 eV (RAg/Zn = 0%). A maximal value of 5.12 eV with Ag doping for RAg/Zn = 1% from its initial value of 4.73 eV for RAg/Zn = 0%. With The defective peak position was blue shifted, with increased Ag-doping, from 536 nm (RAg/Zn = 1%) to 527 nm for RAg/Zn = 2% due to the sizes of the Ag+ and Zn2+ ions. The FL defective peak intensity (ID) in the green region increased with the concentration of Ag used for doping, up to RAg/Zn = 2%. The enhancement in the ID may be due to charge difference between the Zn2+ ions, caused by Ag+ ions. - Highlights: • Structural, optical, electrical, and fluorescence properties are studied. • Various types of nanostructure are formed using heat treatment under hydrogen. • The work function and optical band-gap are tuned via Ag doping. • A 30 fold enhancement fluorescence is obtained with Ag doping. • The shifting of the FL positions is due to the size of Ag+ and Zn2+ ions

Availability note (English)

Available from http://dx.doi.org/10.1016/j.jallcom.2015.05.243

Additional details

Identifiers

DOI
10.1016/j.jallcom.2015.05.243;
PII
S0925-8388(15)30016-5;

Publishing Information

Journal Title
Journal of Alloys and Compounds
Journal Volume
647
Journal Page Range
p. 566-572
ISSN
0925-8388
CODEN
JALCEU

INIS

Country of Publication
Netherlands
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
47023627
Subject category
S77: NANOSCIENCE AND NANOTECHNOLOGY;
Descriptors DEI
ABSORPTION; ALUMINIUM ADDITIONS; ANNEALING; CARRIER DENSITY; CURRENT DENSITY; DOPED MATERIALS; FERMI LEVEL; FLUORESCENCE; HYDROGEN; IMPURITIES; NANOSTRUCTURES; OPTICAL PROPERTIES; RED SHIFT; SILVER ADDITIONS; SOL-GEL PROCESS; THICKNESS; THIN FILMS; WORK FUNCTIONS; ZINC IONS; ZINC OXIDES
Descriptors DEC
ALLOYS; ALUMINIUM ALLOYS; CHALCOGENIDES; CHARGED PARTICLES; DIMENSIONS; ELEMENTS; EMISSION; ENERGY LEVELS; FILMS; FUNCTIONS; HEAT TREATMENTS; IONS; LUMINESCENCE; MATERIALS; NONMETALS; OXIDES; OXYGEN COMPOUNDS; PHOTON EMISSION; PHYSICAL PROPERTIES; SILVER ALLOYS; SORPTION; TRANSITION ELEMENT ALLOYS; ZINC COMPOUNDS

Optional Information

Copyright
Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.