Construction of a 2D layered zinc sulfite with proton conductivity

Using 1-ethylimidazole as ligand, a new zinc sulfite Zn(SO3)(C5N2H8) (1) has been synthesized under hydrothermal condition. Compound 1 shows two-dimensional layered structure constructed with triple-fused 4-rings (Zn4S4) motifs via corner-sharing oxygen atoms. The 12-MR windows are presented in the bc plane. The 1-ethylimidazole molecules are grafted onto the Zn atoms of two sides of this layer and the ethyl groups of the 1-ethylimidazole molecules exclusively protrude into the interlayer region. Alternating-current impedance analysis demonstrates compound 1 displays remarkable proton conductivity which relays on the relative humidity (RH). Under 98% RH, the value can reach up to 1.80 x 10(-3) S cm(-1) at 75 degrees C. The Ea is 0.52 eV at 98% RH, attributed to the vehicle mechanism by water molecules serving as proton carriers to carry protons.

Automated summary

A new zinc sulfite compound with a two-dimensional layered structure has been synthesized, showing remarkable proton conductivity depending on relative humidity.