Recent advances in MOFs-based proton exchange membranes

Design of Flexible Metal–Organic Framework-Based Superprotonic Conductors and Their Fabrication with a Polymer into Proton Exchange Membranes

“…The study of proton conductivity and development of proton-conducting materials are of immense importance from the perspective of renewable energy research owing to the widespread use of these materials in fuel cells, electrochemical sensors, electrolyzers, and CO 2 convertors, among others. , The early research studies had focused on the development of proton conductors from materials such as organic polymers, ceramic oxides, solid acids, intercalation compounds, etc. , But in the past few years, metal–organic frameworks (MOFs) have been explored extensively as proton conductors, − or as proton exchange membranes (PEMs) in combination with suitable polymers. − This is due to the crystalline nature, high surface area, and ease of structural tunability in MOFs, which render the material viable for many applications. − The wide range of metal ions and organic linkers provides us with a plethora of MOFs with different surface functionalities, pores and channels, along with an additional scope of postsynthetic modification …”

Water-Mediated Proton Conduction in Metal–Organic Frameworks with High Water Stability Constructed by a Terpyridine Tricarboxylate Ligand

“…Metal–organic frameworks (MOFs) have attracted much attention in the field of proton conduction. So far, a number of exciting research results have been described, such as the preparation of a considerable number of MOFs with proton conductivities as high as 10 –1 S·cm –1 , − which motivates people to be confident in the research in this field. Specifically, because of their crystallinity, designability, and tunable structures, along with a functionally customizable porosity and adjustable channels, the proton-conductive properties of MOFs containing Mn, Co, and Ni ions have received continuous interest over the years. − Moreover, with ingenious design, more hydrophilic sites, proton carriers (such as H 2 O, acidic functional groups), and uncoordinated functional units (−COOH or SO 4 2– anion) can be easily incorporated into MOFs. , Mediated by the pores, channels, or layers of the MOFs, they can be assembled together to form a rich H-bonded network that serves as efficient proton transport channels.…”

Comparative study on proton conductivity of a polypyridinyl multicarboxylate-based hydrogen-bonded organic framework and related chitosan composite membrane

“…Although the optimal σ value of the CS/HOF-4 hybrid membrane is smaller than that of some CS/MOF composite membranes, 16,21,22 it is comparable to the values of some composite membranes 17–19 and greater than those of some other composite membranes under similar test conditions 14,20,31,32 (see Table 1). It should be noted that the composite membrane prepared by us represents the first time that a HOF has been introduced into the CS membrane, which is relatively rare.…”