Protic plastic crystal/PVDF composite membranes for Proton Exchange Membrane Fuel Cells under non-humidified conditions

Abstract

Composite membranes based on the protic plastic crystal N,Ndimethylethylenediammonium triflate [DMEDAH][TFO] and poly(vinylidene fluoride) (PVDF) nanofibers have been developed for proton exchange membrane fuel cells (PEMFCs) under non-humidified conditions. The effect of addition of 5 mol% triflic acid or 5 mol% of the base N,N-dimethylethylenediamine on the thermal and transport properties of the material is discussed. The acid-2 doped plastic crystal reports more than double the ionic conductivity of the pure plastic crystal. The effects of doping the plastic crystal and the composites, with acid or base, on the ionic conductivity and fuel cell performance are reported. Composite membranes based on PVDF nanofibers and [DMEDAH][TFO] were tested in a single PEMFC. The results show the potential of these composite membranes to be used as electrolytes in this electrochemical application without external humidification.

Toward High‐Energy‐Density Lithium Metal Batteries: Opportunities and Challenges for Solid Organic Electrolytes

“…Compared with molecular plastic crystals, such as succinonitrile, OIPCs are considered as safe electrolytes due to their ionic nature resulting in nonvolatility and negligible vapor pressure even after melting. Thus, OIPCs have been extensively investigated and used in a range of devices, such as proton exchange membrane fuel cells, dye‐sensitized solar cells, capacitors, and next generation high energy batteries (e.g., Li‐, Na‐batteries) . There are several reviews that have summarized the classification and basic physical chemical properties of OIPCs, which are not the focus of this section.…”

The influence of interfacial interactions on the conductivity and phase behaviour of organic ionic plastic crystal/polymer nanoparticle composite electrolytes

“…In other instances, however, OIPCs and polymer interactions have resulted in reduced ionic conductivity and improved ordering of the OIPC matrix. 21 For instance, Rao et al studied the effect of electrospun PVDF nanofibers on 1-(N,N-dimethylammonium)-2-(ammonio)ethane triflate ([DMEDAH2][Tf]2) protic OIPC (POIPC). Unlike other studies, they recorded a significant decrease in ionic conductivity.…”

Decoupled ion mobility in nano-confined ionic plastic crystal

“…A fully hydrated Nafion s , for example, can easily achieve conductivity of 410 À1 S cm À1 , 1 whereas hardly any polymer electrolyte can achieve a bulk conductivity (without solvent) of the order of 10 À3 S cm À1 at room temperature. 2 Organic ionic plastic crystals (OIPCs) represent a unique family of solid materials with demonstrated applications as solid-state electrolytes for lithium and sodium ion batteries, 3,4 fuel cells, 5,6 and dye-sensitized solar cells. [7][8][9] OIPCs typically consist of a bulky organic cation coupled with a highly symmetric anion.…”