Significantly lowered activation energy in proton conductor by Mg substitution in a layered Ni metal-organic framework

Designs and developments of proton conductors are highly important in chemistry and energy fields. In this study, a novel metal-organic framework H(2)DAB-MgNi(ox)(3) was synthesized. X-ray powder diffraction, scanning transmission electron microscopy, and scanning transmission electron microscopy-energy-dispersive X-ray mapping measurements demonstrated that the H(2)DAB-MgNi(ox)(3) had a solid-solution structure, with the homogeneous distribution of Mg and Ni elements. The proton conductivity of H(2)DAB-MgNi(ox)(3) was enhanced from that of H(2)DAB-Ni-2(ox)(3) at 95% relative humidity by Mg substitution.