An unexpected imidazole-induced porphyrinylphosphonate-based MOF-to-HOF structural transformation leading to the enhancement of proton conductivity

Ekaterina A. Zhigileva, Yulia Yu Enakieva*, Vladimir V. Chernyshev*, Ivan N. Senchikhin, Liudmila I. Demina, Alexander G. Martynov, Irina A. Stenina, Andrey B. Yaroslavtsev, Yulia G. Gorbunova, Aslan Yu Tsivadze

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Post-synthetic modification of proton-conducting metal-organic frameworks (MOFs) by loading small molecules capable of generating protons into pores is an efficient approach for developing a new type of material with improved ionic conductivity. Herein, the synthesis, characterization and proton conductivity of a novel electroneutral MOF based on palladium(ii) meso-tetrakis(4-(phosphonatophenyl))porphyrinate, IPCE-1Pd, are reported. The exposure of the obtained framework to imidazole by the diffusion vapor method has surprisingly led to its complete crystal-to-crystal MOF-to-HOF transformation, resulting in the formation of a novel hydrogen-bonded organic framework (HOF) IPCE-1Pd_Im, which is the first example of such kind of structural change among all known MOFs. This modification has led to an almost 25-fold increase in the proton conductivity in comparison with the pristine MOF, reaching up to 6.54 × 10−3 S cm−1 at 85 °C and 95% relative humidity, which is one of the highest values among all known porphyrin-based HOFs.

Original languageEnglish
Pages (from-to)16345-16354
Number of pages10
JournalDalton Transactions
Volume53
Issue number39
DOIs
Publication statusPublished - 24 Sept 2024
Externally publishedYes

Funding

The authors thank the Russian Science Foundation (grant no. 23-23-00516) for financial support. The synthesis of precursors was supported by the Ministry of Science and Higher Education of the Russian Federation. We are grateful to Prof. Andrey A. Shiryaev for the assistance with VT-PXRD measurements and Dr Anna A. Sinelshchikova for a fruitful discussion about the crystal structures of new materials. MALDI TOF MS, IR, TGA, SEM, XPS, and PXRD diffraction measurements along with the proton conductivity experiments were performed at the CKP FMI of the Frumkin Institute of Physical Chemistry and Electrochemistry, RAS, and using the equipment of the JRC PMR IGIC RAS.

All Science Journal Classification (ASJC) codes

  • Inorganic Chemistry

Fingerprint

Dive into the research topics of 'An unexpected imidazole-induced porphyrinylphosphonate-based MOF-to-HOF structural transformation leading to the enhancement of proton conductivity'. Together they form a unique fingerprint.

Cite this