Fabrication of cellulose acetate‐based radiation grafted anion exchange membranes for fuel cell application

Abstract

Novel cellulose acetate-based anion exchange membranes (CA-AEM) are successfully synthesized via gamma radiation grafting as a possible renewable alternative to commercial AEMs. Using CA film precursors with degree of acetylation of 2.5, the synthesized AEM shows a high ion exchange capacity of 2.15 mmol g −1 obtained at high degree of grafting of 45%. It was determined using thermogravimetric analysis that the radiation-grafted CA-AEM has stable amine functional groups under oxygen environment within the normal operating temperature range of alkaline fuel cells. The CA-AEM also exhibits appreciable performance over a range of temperatures, with a highest ionic conductivity of up to 0.163 S cm −1 depending on the synthesis parameters. Results revealed that membranes prepared using gamma radiation dose of 31 kGy and above are susceptible to mechanical and dimensional instability due to increased water uptake and degree of swelling. Further study should consider the balance between grafting parameters and the desired hydrophysical properties.

Fabrication of Cellulose Acetate-Based Proton Exchange Membrane with Sulfonated SiO2 and Plasticizers for Microbial Fuel Cell Applications

“…An initial weight loss of around 3.2% was observed below 100 °C in all the membranes, which was due to the evaporation of water and solvent in the membranes [ 50 ]. The main thermal degradation of cellulose acetate polymer chains, which represents the decomposition of CO 2 , CO, H 2 O, and acetic acid, was observed in the range of ~300 °C–400 °C [ 49 , 51 ]. Finally, the carbonization of the degraded products started at the temperature of around ~400 °C [ 52 ].…”

Aryl ether-free polymer electrolytes for electrochemical and energy devices

“…395 There is also some interest in making RG-AEMs from non-fluorinated non-polyethylene substrates such as cellulose acetate, and Nylon-6,6 nanofibrous sheets. 396,397 The crystallinity of the substrate can also influence the final properties of RG-PEMs and RG-AEMs, as their final nano-morphologies can be complex. [398][399][400][401][402] The radicals formed on irradiation tend to be more stable in the crystalline domains, but they can migrate to the interphase and amorphous domains, 388,389 where they will react with any oxygen species, and grafting will predominantly propagate into the amorphous domains.…”

Review: chitosan-based biopolymers for anion-exchange membrane fuel cell application

“…To address this challenge, researchers have explored various strategies to enhance the conductivity of cellulose-based AEMs. In particular, referring to the conductivity problem of the cellulose-based membrane, there are numerous types of agents to improve the conductivity of AEM, including PDDA [148], trimethylaluminium [149], 2,2-azobis(2methylpropionitril) and N-bromosuccinimide [150]. Compared to others, DABCO (1,4-diazabicyclo high conductivity moreover, the membrane showed good dimensional and alkaline stability owing to cross-linking with compatible polymer [38].…”