CdSe/ZnS QD@CNT nanocomposite photocathode for improvement on charge overpotential in photoelectrochemical Li-O2 batteries

Publication date: 1 October 2018
Source:Chemical Engineering Journal, Volume 349
Author(s): Vediyappan Veeramani, Yu-Hsiang Chen, Hung-Chia Wang, Tai-Feng Hung, Wen-Sheng Chang, Da-Hua Wei, Shu-Fen Hu, Ru-Shi Liu
Li-ion batteries play a significant role in portable electronic devices in the running world. However, the limited energy density still needs to be improved for the growing future. Hence, we developed a photocathode nanocomposite material composed of Cadmium Selenide/Zinc Sulfide Quantum Dots with Carbon nanotube (CdSe/ZnS QD@CNT) for an efficient and tunable performance of the photoelectrochemical Li–O2 battery system to overcome the key issue of overpotential. The QD and CNT networks can provide efficient transportation paths of the electron–hole pairs and the O2 gas and lithium ions, respectively. The charging voltage of the photoelectrode is 2.65–4.0 V; therefore, decreased overpotential was due to efficient oxidation of Li2O2 by photoexcited electron–hole pairs by using QDs, resulting in a long-term operational stability over 100 cycles. On the basis of the advantages, the QDs exhibit efficient potential in Li–O2 batteries.

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