resumo
The need for developing more sustainable electrochemical energy storage and conversion devices prompted us to develop novel bio-based membranes based on poly(lactic acid) (PLA) and imidazolium ionic liquids (ILs) to act as an electrolyte in energy conversion devices, such as fuel cells. PLA membranes based on [C(4)C(1)im][PF6] and [C(4)C(1)im][BF4] present different morphologies according to the anion nature and high thermal stability (>300 degrees C). Scanning electron microscopy and energy-dispersive spectroscopy analyses show that [C(4)C(1)im][BF4] tends to be isolated inside small pore cavities, which prevents the IL from leaching out of the membranes. Owing to this improved retention capacity of [C(4)C(1)im][BF4] and to the hydrophilic character of the IL anion, the PLA-[C(4)C(1)im][BF4] blends present conductivity values higher than 0.01 S cm(-1) at 98% RH and 94 degrees C. The work further demonstrates the operation of a PLA-[C(4)C(1)im][BF4]-based oxygen/hydrogen fuel cell with an open-circuit voltage above 0.9 V.
palavras-chave
POLY(LACTIDE) STEREOCOMPLEXES; PHYSICOCHEMICAL PROPERTIES; POLYLACTIC ACID; LIQUIDS; TETRAFLUOROBORATE; DEGRADATION; WATER
categoria
Chemistry; Science & Technology - Other Topics; Materials Science
autores
Barbosa, PC; Mickalev, S; Barros-Timmons, A; Figueiredo, FM
nossos autores
Grupos
G1 - Materiais Porosos e Nanossistemas
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
Projectos
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
agradecimentos
This work was developed within the scope of the projects CICECO.Aveiro Institute of Materials (UIDB/50011/2020 & UIDP/50011/2020) and UniRCell (ref. SAICTPAC-00322015, POCI-01-0145-FEDER-016422), financed by national funds through the Portuguese Foundation for Science and Technology/MCTES (FCT I.P.) and when appropriate cofinanced by FEDER under the PT2020 Partnership Agreement. The research contract of P.B. is funded by national funds (OE), through FCT, I.P., in the scope of the framework contract foreseen in the numbers 4, 5, and 6 of article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. The ILs, [C4C1im][PF6] and [C4C1im][BF4], were kindly supplied by Joa~o A. P. Coutinho's research group at CICECO Portugal.