Lanthanide‐Hypophosphite Frameworks with Guanidinium Guest Showing High Proton Conductivity.

Main observation and conclusion: Proton‐conductive metal‐organic frameworks (MOFs) have attracted great attention for their promising application in membrane fuel cells. To explore proton‐conductive MOFs with high performance, here we present four lanthanide‐hypophosphite frameworks with distinct amine guests. These complexes possess a general formula [AH][Gd2(H2PO2)7] (AH = protonated amines). Due to the rich hydrogen bond networks, complex 1 with guanidinium as guest shows high proton conductivity of 1.75 × 10–2 S·cm–1 at a relative humidity of 97% (368 K). We also studied the magnetic properties of complex 1 and reveal that the hypophosphite ligand transfers weak antiferromagnetic interactions between Gd3+ ions. [ABSTRACT FROM AUTHOR]