High temperature composite membranes based on polybenzimidazole and dendrimer amine functionalized SBA-15 mesoporous silica for fuel cells

Abstract

In this work SBA-15, a melamine-based functionalized SBA-15 mesoporous silica with a dicationic ionic liquid was used in order to improve the physicochemical properties of phosphoric acid doped polybenzimidazole membranes for application in HT-PEMFCs.

Recent Progress in the Development of Composite Membranes Based on Polybenzimidazole for High Temperature Proton Exchange Membrane (PEM) Fuel Cell Applications

“…Recently, Rajabi et al prepared composite membranes by introducing melamine-based dendrimer amines (MDA) with mesoporous silica (SBA-15), and 1,3-di(3-methylimidazolium) propane dibromide dicationic ionic liquid (pr(mim) 2 Br 2 ) (DIL), the membranes were doped with PA and were used to improve the proton conductivity [ 75 ]. The APBI-DIL 4.5 -MDA 1.5 composite membranes exhibit a proton conductivity of 0.22 S/cm at 180 °C under dry conditions.…”

A Review of Recent Developments and Advanced Applications of High-Temperature Polymer Electrolyte Membranes for PEM Fuel Cells

“…More attempts have recently been made to modify the PA-PBI membranes, including PBI crosslinking, PBI sulfonation, PBI analogue structure preparation, PBI-based blend membrane synthesis, and composite and nanocomposite membrane synthesis. In order to improve the thermal and mechanical stability of PA-doped PBI-based composite membranes, Rajabi et al [141] used SBA-15 mesoporous silica (MDASBA-15), and 1,3-di(3-methylimidazolium) propane dibromide dicationic ionic liquid (pr(mim) 2 Br 2 ), which was a new generation of ionic liquids containing two mono anions and two single-charged cations known as dicationic ionic liquids. Two aromatic rings connected by an alkyl chain can make up the cations in the dicationic ionic liquids.…”

“…The bound-and unbound-PA molecules and H 2 PO 4 − anion in PA-doped PBI-based membranes mainly participate in the proton conduction through the 'Grotthus' mechanism [144]. Generally, the PA doping level (PA dop ) has been achieved by dipping the membranes into PA (85 wt.%) for five days [141]. In this method, the membranes were dried in a vacuum oven at 60 • C for 24 h, and the doping level was determined by measuring the absorbed acid weight by the membranes.…”

Desenvolvimento de membranas não fluoradas a base de PBI para aplicação em células a combustível de etanol direto de alta temperatura

“…Para membranas de PEMFC, podem ser utilizados diversos compostos inorgânicos na forma ou não de nanopartículas. São exemplos de compostos inorgânicos: dióxido de silício (SiO2) [31][32][33][34][35], dióxido de titânio (TiO2) [36,37], ácidos silicotungstico (H4[Si(W3O10)4) [38,39], materiais com zircônia (ZrO2) [40,41]. Em geral, a componente inorgânica tem como característica uma elevada hidrofilicidade, a qual permite suprir a água, mantida estruturalmente na sua composição, perdida pela membrana com o aumento da temperatura.…”

“…No caso do uso do dióxido de silício (sílica)objeto desse estudopodem ser utilizadas diversas variações funcionalizadas ou não, e com diferentes estruturas e tamanhos de partículas [31][32][33][34][35].…”