Developing solid electrolytes with high intrinsic proton conductivity over a broad temperature range is crucial for proton exchange membrane fuel cells. We report a new layered cadmium chlorophosphate crystal, (C3N2H5)CdCl(H3/2PO4)2 (CdClPO4-ImH), featuring highly ordered one-dimensional proton transport channels formed by host-guest synergy between imidazolium cations and inorganic layers. Structural and theoretical analyses revealed a continuous hydrogen-bonding network that promotes efficient proton hopping. The material shows excellent proton conductivity from -20 to 90 °C, reaching 2.57 × 10-2 S cm-1 at 90 °C and 95% relative humidity (RH). An undoped intrinsic membrane delivered a peak power density of 104 mW cm-2 in a H2/O2 fuel cell.
Jin et al. (Thu,) studied this question.