Structural features of proton-conducting metal organic and covalent organic frameworks

CrystEngComm ◽  
2020 ◽  
Vol 22 (39) ◽  
pp. 6425-6443
Author(s):  
Pampa Jhariat ◽  
Priyanka Kumari ◽  
Tamas Panda

Proton conductivity in MOFs and COFs have been attracted due to their applicability as electrolytes in proton exchange membrane fuel cells. A short overview with recent updates on the structural features of MOFs and COFs for proton conduction are presented here.

2020 ◽  
Vol 49 (47) ◽  
pp. 17130-17139
Author(s):  
Lu Feng ◽  
Hao-Bo Hou ◽  
Hong Zhou

As newly emerging proton-conducting materials, metal–organic frameworks (MOFs) have been attracting wide attention in the field of proton exchange membrane fuel cells.


Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1871 ◽  
Author(s):  
Ae Kim ◽  
Mohanraj Vinothkannan ◽  
Kyu Lee ◽  
Ji Chu ◽  
Sumg Ryu ◽  
...  

We designed and synthesized a series of sulfonated poly(arylene ether sulfone) (SPES) with different hydrophilic or hydrophobic oligomer ratios using poly-condensation strategy. Afterward, we fabricated the corresponding membranes via a solution-casting approach. We verified the SPES membrane chemical structure using nuclear magnetic resonance (1H NMR) and confirmed the resulting oligomer ratio. Field-emission scanning electron microscope (FE-SEM) and atomic force microscope (AFM) results revealed that we effectively attained phase separation of the SPES membrane along with an increased hydrophilic oligomer ratio. Thermal stability, glass transition temperature (Tg) and membrane elongation increased with the ratio of hydrophilic oligomers. SPES membranes with higher hydrophilic oligomer ratios exhibited superior water uptake, ion-exchange capacity, contact angle and water sorption, while retaining reasonable swelling degree. The proton conductivity results showed that SPES containing higher amounts of hydrophilic oligomers provided a 74.7 mS cm−1 proton conductivity at 90 °C, which is better than other SPES membranes, but slightly lower than that of Nafion-117 membrane. When integrating SPES membranes with proton-exchange membrane fuel cells (PEMFCs) at 60 °C and 80% relative humidity (RH), the PEMFC power density exhibited a similar increment-pattern like proton conductivity pattern.


Author(s):  
guomei wu ◽  
Wen-Jing Li ◽  
Libin Yang ◽  
chenxi zhang

Abstract Proton exchange membrane (PEM) is a key component of proton exchange membrane fuel cells (PEMFCs). In recent years, metal organic framework (MOF) and its composite membranes have become the research hotspots. [Co(L-Glu)(H2O)•H2O]n (Co-MOF, L-Glu = L-glutamate) was synthesized by hydrothermal method. Co2+ ions are coordinated with L-Glu ligands and water molecules to form one-dimensional chains extending along the a-axis, which are further bridged by L-Glu ligands to form a three-dimensional network structure. AC impedance analysis shows that the proton conductivity of Co-MOF reaches 3.14×10-4 S•cm-1 under 98% relative humidity (RH) and 338 K. To improve proton conductivity, different contents of Co-MOF were added in chitosan (CS) to form composite membranes Co-MOF@CS-X (mass fraction X= 5%, 10%, 15% wt). The results show the proton conductivity of the Co-MOF@CS-10 composite membrane is 1.73×10-3 S•cm-1 at 358 K and 98% RH, which is more than 5 times that of Co-MOF. As far as we known, this is the first composite made of amino acid MOFs and CS as proton exchange membrane. Furthermore, Co-MOF has an obvious quenching effect on L-histidine in aqueous solution, which can detect the content of L-histidine in water with high sensitivity, and the detection limit is 1×10-7 M.


Langmuir ◽  
2015 ◽  
Vol 32 (1) ◽  
pp. 359-365 ◽  
Author(s):  
Ravikumar Thimmappa ◽  
Mruthyunjayachari Chattanahalli Devendrachari ◽  
Alagar Raja Kottaichamy ◽  
Omshanker Tiwari ◽  
Pramod Gaikwad ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document