Applications of quantum dot membrane electrolytes in LT-SOFCs

• Published in: Journal of alloys and compounds 2022-12, Vol.929, p.167213, Article 167213
• Main Authors: Cai, Hongdong, Zheng, Dan, Xia, Chen, Wang, Xunying, Dong, Wenjing, Ganesh, K.Sivajee, Wang, Hao, Wang, Baoyuan
• Format: Article
• Language: English
• Subjects: Cerium oxides; Electrolytes; Electrolytic cells; Energy band; Energy bands; Fuel cells; Low temperature; Maximum power density; Membranes; Quantum dot; Quantum dots; Semiconductor-ions membrane electrolyte; Short circuits; Solid oxide fuel cell; Solid oxide fuel cells; Titanium dioxide
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2022.167213

CeO2 existed in the form of quantum dots were used in fuel cell electrolytes for the first time after being compounded with semiconductor TiO2. The TiO2 @xCeO2 (x = 1,2,3) was evaluated as the membrane electrolyte for the semiconductor-ions membrane electrolyte fuel cells using H2 as fuels. The maximum power density of the TiO2 @ 2CeO2 quantum dot electrolyte at 550 °C reaches 839 mW cm−2, and the ion conductivity reaches 0.11 S cm−1, which is higher than the physically mixed TiO2/CeO2 composite under the same operating environment. The energy band structure and rectification characteristics test show that the cell based on TiO2/CeO2 electrolyte membrane has a physical junction effect, which can prevent electrons from passing through the interior and effectively avoid short-circuit problems. This study shows that the TiO2 @xCeO2 (x = 1,2,3) composite in quantum dots form is a promising electrolyte that can promote the development of low-temperature solid oxide fuel cell. [Display omitted] •TiO2 particles were modified by CeO2 quantum dots (QD) to fabricate TiO2 @xCeO2 (x = 1,2,3) hetero-structure.•The TiO2 @CeO2 (QD) heterojunction was beneficial to ion conduction, and the ionic conductivity reached 0.11 S cm−1 at 550 °C.•The TiO2 @CeO2 (QD) heterojunction can block the electrons generated from the reduction of Ce4+.•The energy band alignment was response for the function of quantum dot.