Preparation and performance of different amino acids functionalized titania-embedded sulfonated poly (ether ether ketone) hybrid membranes for direct methanol fuel cells

• Published in: Journal of membrane science Vol. 463; pp. 134 - 144
• Main Authors: Wu, Hong, Cao, Ying, Shen, Xiaohui, Li, Zhen, Xu, Tao, Jiang, Zhongyi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.08.2014; Elsevier
• Subjects: Amino acids; Applied sciences; Chemistry; Colloidal state and disperse state; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Ethers; Exact sciences and technology; Fuel cells; General and physical chemistry; Histidine; Hybrid membranes; Ketones; Membranes; Methyl alcohol; Particle size; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Proton conductivity; Sulfonated poly (ether ether ketone); Titania submicrospheres; Titanium dioxide; Hybrid membranes; oxidized l-cysteine; Titania submicrospheres; sulfonation degree; O-phospho-l-serine; sulfonated poly(ether ether ketone); ion-exchange capacity; Proton conductivity; Amino acids; aspartic acid; Sulfonated poly (ether ether ketone); histidine; Transition element compounds; Alcohol; Polymer; Submicron particle; Aminoacid; Preparation; Alkanol; Membrane; Spherical particle; Titanium oxide; Fuel cell; Methanol
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2014.03.058

A series of amino acid functionalized titania submicrospheres were synthesized and incorporated into sulfonated poly (ether ether ketone) (SPEEK) to fabricate organic–inorganic hybrid proton exchange membranes. Pristine TiO2 with a uniform particle size of ~200nm were synthesized and functionalized with four kinds of amino acids including oxidized l-cysteine, O-phospho-l-serine, aspartic acid and histidine, designated as TiO2–Scys, TiO2–Pser, TiO2–Asp and TiO2–His, respectively. The effects of amino acid attribute on the membrane properties were investigated. At the filler content of 15wt%, the TiO2–Scys embedded membrane exhibited the highest proton conductivity of about 5.98×10−3Scm−1 (20°C, 100% RH), while the TiO2–His embedded membrane exhibited the lowest conductivity due to the strong acid-base interaction between the basic imidazole groups of histidine and the sulfuric acid groups of SPEEK. The TiO2–Pser embedded membrane exhibited the highest selectivity of 17.10×103Sscm−1. In addition, the methanol crossover of the hybrid membranes was reduced by two folds, and the anti-swelling property and thermal stability of the hybrid membranes were also enhanced. •Titania submicrospheres modified with four kinds of amino acids were synthesized.•The submicrospheres were incorporated into SPEEK to prepare hybrid membranes.•Effect of different amino acids on proton conductivity of PEM was studied.•The hybrid membranes showed enhanced proton conductivity and methanol resistance.