In 2022,Yang, Lincan; Wang, Zhiqian; Wang, Fanghui; Wang, Zhongming; Zhu, Hong published an article in Journal of Membrane Science. The title of the article was 《Poly(aryl piperidinium) anion exchange membranes with cationic extender sidechain for fuel cells》.Electric Literature of C6H11NO The author mentioned the following in the article:
Anion-exchange membrane fuel cells (AEMFCs) is a promising solution to decrease the cost of fuel cell, because it is adaptable to non-noble-metals catalysts and low-cost stack components. However, anion exchange membranes (AEMs), a crucial component of AEMFCs devices, with desired properties (high ions conductivity, excellent chem. stability, robust mech. strength, etc.) are currently unavailable. In this paper, poly(biphenyl N-methylpiperidine) (PBP) was synthesized as the backbones of AEMs, which could provide good chem. stability and robust mech. strength. Quaternary ammonium cations containing various types of substituent sidechains, including hydrophobic alkyl chain, hydrophilic PEG chain and multi-PEG chains, were introduced onto the PBP backbones, and resulting AEMs were named PBP-alkyl, PBP-PEG and PBP-TPEG, resp. The relationship between AEMs structure and performance were studied, and mol. dynamics (MD) simulations were carried out to microcosmically reveal the mechanism of structure-activity relationship. All the PBP-based AEMs have acceptable alk. stability and performance loss is less than 10% under 2 M NaOH at 80 °C for about 500 h. PBP-PEG has the highest ions conductivity of 97.3 mS cm-1 and lowest water uptake (WU), while PBP-TPEG has the lowest ions conductivity of 56.1 mS cm-1 and highest WU. For single cell evaluations at 80 °C under H2/O2 condition, AEMFC containing PBP-PEG membrane bursts out a highest peak power d. of 373 mW cm2, while PBP-alkyl and PBP-TPEG only achieve 133 and 93 mW cm-2, resp. MD results show the water channel of PBP-PEG is denser and more continuous than other structures, and the proportion of completely hydrated transport is higher than other structures, which contributes to the increase of overall performance. On the other hand, DFT results show the low basicity and strong hydrophily of cation containing multi-PEG substituents leads to the poor performance of PBP-TPEG. Therefore, for the design of AEMs mol. structures with outstanding performances, hydrophilic PEG spacer chain is more effective than hydrophobic alkyl spacer chain, and PEG is more effective as a spacer chain than as an extender chain. The experimental part of the paper was very detailed, including the reaction process of 1-Methyl-4-piperidone(cas: 1445-73-4Electric Literature of C6H11NO)
1-Methyl-4-piperidone(cas: 1445-73-4) is a member of piperidine. Piperidine is ubiquitous structural motif widely occurred in diverse synthetically and naturally occurring bioactive molecules. Piperidines are an immensely important class of compounds medicinally: the piperidine ring is the most common heterocyclic subunit among FDA approved drugs.Electric Literature of C6H11NO
Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem