A new optical carbon dioxide sensor based on the colormetric change of pH indicator α-naphtholphthalein with the internal reference fluorescent CIS/ZnS quantum dots (QDs) was developed. The luminescence intensity of CIS/ZnS QDs increased with increasing carbon dioxide concentration. The sensing films consisting of α-naphtholphthalein in polyIBM and CIS/ZnS QDs in polystyrene layer. The sensitivity of optical carbon dioxide sensor is quantified in terms of the ration I₁₀₀/I₀, where I₁₀₀ and I₀ represent the detected luminescence intensities in pure carbon dioxide and pure nitrogen environments, respectively. The experimental result reveals that the new optical carbon dioxide sensor has sensitivity of I₁₀₀/I₀=13.4.

Date Published: 23 April 2017
PDF: 4 pages
Proc. SPIE 10323, 25th International Conference on Optical Fiber Sensors, 103231M (23 April 2017); doi: 10.1117/12.2255810

Published in SPIE Proceedings Vol. 10323:
25th International Conference on Optical Fiber Sensors
Youngjoo Chung; Wei Jin; Byoungho Lee; John Canning; Kentaro Nakamura; Libo Yuan, Editor(s)