ZnO for Solar Cell and Thermoelectric Applications
Abstract
ZnO-based materials show promise in energy harvesting applications, such as piezoelectric, photovoltaic and thermoelectric. In this work, ZnO-based vertical Schottky barrier solar cells were fabricated by MOCVD deposition of ZnO thin films on ITO back ohmic contact, while Ag served as the top Schottky contact. Various rapid thermal annealing conditions were studied to modify the carrier density and crystal quality. Greater than 200 nm thick ZnO films formed polycrystalline crystal structure, and were used to demonstrate Schottky solar cells. I-V characterizations of the devices showed photovoltaic performance, but but need further development. This is the first demonstration of vertical Schottky barrier solar cell based on wide bandgap ZnO film. Thin film and bulk ZnO grown by MOCVD or melt growth were also investigated in regards to their room- temperature thermoelectric properties. The Seebeck coefficient of bulk ZnO was found to be much larger than that of thin film ZnO at room temperature due to the higher crystal quality in bulk materials. The Seebeck coefficients decrease while the carrier concentration increases due to the crystal defects caused by the charge carriers. The co-doped bulk Zn0:96Ga0:02Al0:02O showed enhanced power factors, lower thermal conductivities and promising ZT values in the whole temperature range (300-1300 K).
Recommended Citation
C. Zhou et al., "ZnO for Solar Cell and Thermoelectric Applications," Proceedings of SPIE - The International Society for Optical Engineering, vol. 10105, article no. 101051K, Society of Photo-optical Instrumentation Engineers, Jan 2017.
The definitive version is available at https://doi.org/10.1117/12.2262772
Department(s)
Electrical and Computer Engineering
Keywords and Phrases
Solar cell; Thermoelectric; Wide bandgap; ZnO
International Standard Book Number (ISBN)
978-151060651-7
International Standard Serial Number (ISSN)
1996-756X; 0277-786X
Document Type
Article - Conference proceedings
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2024 Society of Photo-optical Instrumentation Engineers, All rights reserved.
Publication Date
01 Jan 2017
Comments
National Science Foundation, Grant CMMI-1560834