Enhancing proton conduction of MOF-74(Co) by encapsulating NH3 molecules

The functional design of efficient and stable proton exchange membrane materials is an important research direction in the field of proton exchange membrane fuel cells (PEMFCs). In this work, ammonia molecules were successfully encapsulated into the one-dimensional pores of MOF-74(Co) through fumigation with ammonia vapor. Alternating current (AC) impedance tests showed that the proton conductivity of NH3 modified NH3@ MOF-74(Co) reaches an impressive value of 6.8 × 10−3 S/cm, being 10000 times that of the pristine MOF-74(Co) at 98% relative humidity (RH) and 50 °C. Various and abundant hydrogen bonds can improve the proton conduction of NH3 modified compound. This strategy provides an efficient and convenient way to construct high proton conducting porous MOFs materials by attaching NH3 molecules.