Improved strategies for DNP-enhanced 2D 1H-X heteronuclear correlation spectroscopy of surfaces

Takeshi Kobayashi; Frédéric A Perras; Umesh Chaudhary; Igor I Slowing; Wenyu Huang; Aaron D Sadow; Marek Pruski

doi:10.1016/j.ssnmr.2017.08.002

Improved strategies for DNP-enhanced 2D ¹H-X heteronuclear correlation spectroscopy of surfaces

Solid State Nucl Magn Reson. 2017 Oct:87:38-44. doi: 10.1016/j.ssnmr.2017.08.002. Epub 2017 Aug 12.

Authors

Takeshi Kobayashi¹, Frédéric A Perras¹, Umesh Chaudhary², Igor I Slowing³, Wenyu Huang³, Aaron D Sadow³, Marek Pruski⁴

Affiliations

¹ Ames Laboratory, U.S. Department of Energy, Ames, IA 50011, USA.
² Department of Chemistry, Iowa State University, IA 50011, USA.
³ Ames Laboratory, U.S. Department of Energy, Ames, IA 50011, USA; Department of Chemistry, Iowa State University, IA 50011, USA.
⁴ Ames Laboratory, U.S. Department of Energy, Ames, IA 50011, USA; Department of Chemistry, Iowa State University, IA 50011, USA. Electronic address: mpruski@iastate.edu.

PMID: 28834782
DOI: 10.1016/j.ssnmr.2017.08.002

Abstract

We demonstrate that dynamic nuclear polarization (DNP)-enhanced ¹H-X heteronuclear correlation (HETCOR) measurements of hydrogen-rich surface species are better accomplished by using proton-free solvents. This approach notably prevents HETCOR spectra from being obfuscated by the solvent-derived signals otherwise present in DNP measurements. Additionally, in the hydrogen-rich materials studied here, which included functionalized mesoporous silica nanoparticles and metal organic frameworks, the use of proton-free solvents afforded higher sensitivity gains than the commonly used solvents containing protons. We also explored the possibility of using a solvent-free sample formulation and the feasibility of indirect detection in DNP-enhanced HETCOR experiments.

Keywords: Catalysis; Dynamic nuclear polarization; Heteronuclear correlation; Solid-state NMR; Surface science.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't