Poly(2,5-benzimidazole)/trisilanolphenyl POSS composite membranes for intermediate temperature PEM fuel cells

• Published in: Journal of Wuhan University of Technology. Materials science edition 2018-02, Vol.33 (1), p.212-220
• Main Authors: Liu, Qingting, Ni, Na, Sun, Quan, Wu, Xiaoxue, Bao, Xujin, Fan, Zhang, Zhang, Rong, Hu, Shengfei, Zhao, Feng, Li, Xiao
• Format: Article
• Language: English
• Subjects: Chemistry and Materials Science; Conductivity; Fillers; Hydrogen bonds; Materials Science; Membranes; Particulate composites; Polyhedral oligomeric silsesquioxane; Proton exchange membrane fuel cells; Thermal stability
• ISSN: 1000-2413; 1993-0437
• DOI: 10.1007/s11595-018-1808-x

Novel organic-inorganic composites were in-situ synthesized by using TriSilanolPhenyl polyhedral oligomeric silsesquioxane (SO-POSS) as fillers and poly(2,5-benzimidazole) (ABPBI) as polymer matrix. The uniformly dispersed 3% SO-POSS particles in ABPBI matrix increased the thermal stability of the composite membranes. It was found that both the water and H 3 PO 4 uptakes were increased significantly with the addition of SO-POSS due to the formation of hydrogen bonds between the POSS and H 2 O/H 3 PO 4 , which played a critical role in the improvement of the conductivity of the composite membranes at temperature over 100 °C. Proton conductivities of H 3 PO 4 doped with 3wt% SO-POSS contained ABPBI membranes increased with the increase of H 3 PO 4 absorbance, reaching the maximum proton conductivity of 2.55 × 10 -3 S·cm -1 at 160 °C, indicating that the ABPBI/SO-POSS composite membrane could be a promising candidate for mid-temperature PEMFCs.