Three-dimensional protonic conductivity in porous organic cage solids

DOI: 10.1038/ncomms12750

Authors: Ming Liu (University of Liverpool) , Linjiang Chen (University of Liverpool) , Scott Lewis (University of Liverpool) , Samantha Y. Chong (University of Liverpool) , Marc A. Little (University of Liverpool) , Tom Hasell (University of Liverpool) , Iain M. Aldous (University of Liverpool) , Craig M. Brown (Center for Neutron Research, National Institute of Standards and Technology) , Martin W. Smith (Defence Science and Technology Laboratory) , Carole A. Morrison (School of Chemistry, University of Edinburgh) , Laurence Hardwick (University of Liverpool) , Andrew I. Cooper (University of Liverpool)
Co-authored by industrial partner: Yes

Type: Journal Paper
Journal: Nature Communications , VOL 7

State: Published (Approved)
Published: September 2016
Diamond Proposal Number(s): 8728

Abstract: Proton conduction is a fundamental process in biology and in devices such as proton exchange membrane fuel cells. To maximize proton conduction, three-dimensional conduction pathways are preferred over one-dimensional pathways, which prevent conduction in two dimensions. Many crystalline porous solids to date show one-dimensional proton conduction. Here we report porous molecular cages with proton conductivities (up to 10−3 S cm−1 at high relative humidity) that compete with extended metal-organic frameworks. The structure of the organic cage imposes a conduction pathway that is necessarily three-dimensional. The cage molecules also promote proton transfer by confining the water molecules while being sufficiently flexible to allow hydrogen bond reorganization. The proton conduction is explained at the molecular level through a combination of proton conductivity measurements, crystallography, molecular simulations and quasi-elastic neutron scattering. These results provide a starting point for high-temperature, anhydrous proton conductors through inclusion of guests other than water in the cage pores.

Diamond Keywords: Fuel Cells

Subject Areas: Chemistry, Materials, Energy


Instruments: I19-Small Molecule Single Crystal Diffraction

Added On: 13/09/2016 16:45

Documents:
ncomms12750.pdf

Discipline Tags:

Energy Storage Earth Sciences & Environment Sustainable Energy Systems Energy Climate Change Physical Chemistry Chemistry Materials Science

Technical Tags:

Diffraction Single Crystal X-ray Diffraction (SXRD)