Lanthanide‐Hypophosphite Frameworks with Guanidinium Guest Showing High Proton Conductivity

• Published in: Chinese journal of chemistry Vol. 39; no. 12; pp. 3381 - 3385
• Main Authors: Li, Quan‐Wen, Li, Zhao‐Yang, Li, Kai, Xia, Bin, Li, Na, Bu, Xian‐He
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY‐VCH Verlag GmbH & Co. KGaA 01.12.2021; Wiley Subscription Services, Inc
• Subjects: Amines; Antiferromagnetism; Conductivity; Fuel cells; Fuel technology; Gadolinium; Hydrogen bonds; Hypophosphite; Lanthanides; Magnetic properties; Metal-organic frameworks; Proton transport; Protons; Relative humidity
• ISSN: 1001-604X; 1614-7065
• DOI: 10.1002/cjoc.202100382

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. Proton‐conductive lanthanide‐hypophosphite frameworks with a general formula [AH][Gd2(H2PO2)7] (AH = protonated amines) were successfully synthesized. Complex [GUA][Gd2(H2PO2)7] (GUA = guanidinium) shows high proton conductivity of 1.75 × 10–2 S·cm–1 at a relative humidity of 97% (368 K). Besides, the hypophosphite ligand passes weak antiferromagnetic interactions between Gd3+ ions.