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Updated: Nov 8, 2025
Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance
Published on: September 5, 2018
Ultrahigh Proton Conduction via Extended Hydrogen-Bonding Network in a Preyssler-Type Polyoxometalate-Based Framework
Tsukasa Iwano1, Kota Shitamatsu2, Naoki Ogiwara1
1Department of Basic Science, School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
Abstract:
The exploration of composition-structure-function relationship in proton-conducting solids remains a challenge in materials chemistry. Polyoxometalate-based compounds have been long considered as candidates for proton conductors; however, their low structural stability and a large decrease in conductivity under reduced relative humidity (RH) have limited their applications. To overcome such limitations, the hybridization of polyoxometalates with proton-conducting polymers has emerged as a promising method. Besides, 4f lanthanide ions possess a high coordination number, which can be utilized to attract water molecules and to build robust frameworks. Herein, a Preyssler-type polyoxometalate functionalized with a 9-coordinate Eu3+ (Eu[P5W30O110K]11-) is newly synthesized and combined with poly(allylamine) with amine moieties as protonation sites. The resulting robust crystalline composite exhibits an ultrahigh proton conductivity >10-2 S cm-1 at 368 K and 90% RH, which is still >10-3 S cm-1 at 50% RH, due to the strengthened and extended hydrogen-bonding network.
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