Details

Autor(en) / Beteiligte

• Rought, Peter
• Marsh, Christopher
• Pili, Simona
• Silverwood, Ian P.
• Sakai, Victoria García
• Li, Ming
• Brown, Martyn S.
• Argent, Stephen P.
• Vitorica-Yrezabal, Inigo
• Whitehead, George
• Warren, Mark R.
• Yang, Sihai
• Schröder, Martin

Titel

Modulating proton diffusion and conductivity in metal–organic frameworks by incorporation of accessible free carboxylic acid groups† †Electronic supplementary information (ESI) available. CCDC 1849703–1849705. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c8sc03022g

Ist Teil von

• Chemical science (Cambridge), 2018-11, Vol.10 (5), p.1492-1499

Ort / Verlag

Royal Society of Chemistry

Erscheinungsjahr

2018

Link zum Volltext

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• The proton conductivity of barium-based MOFs MFM-510 to MFM-512 are analysed in relation to the absence and presence of free –COOH groups in the pores. Three multi-carboxylic acid functionalised ligands have been designed, synthesised and utilised to prepare the new barium-based MOFs, MFM-510, -511, and -512, which show excellent stability to water-vapour. MFM-510 and MFM-511 show moderate proton conductivities (2.1 × 10 –5 and 5.1 × 10 –5 S cm –1 , respectively) at 99% RH and 298 K, attributed to the lack of free protons or hindered proton diffusion within the framework structures. In contrast, MFM-512, which incorporates a pendant carboxylic acid group directed into the pore of the framework, shows a two orders of magnitude enhancement in proton conductivity (2.9 × 10 –3 S cm –1 ). Quasi-elastic neutron scattering (QENS) suggests that the proton dynamics of MFM-512 are mediated by “free diffusion inside a sphere” confirming that incorporation of free carboxylic acid groups within the pores of MOFs is an efficient albeit synthetically challenging strategy to improve proton conductivity.