1 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, the Chinese Academy of Sciences, Wuhan 430071, PR China.
Detailed structure of Brønsted acid sites on the surface of SO3/Al2O3 catalyst has been proposed based on 1H/27Al TRAPDOR NMR results and the acidity of the catalyst has also been characterized by NMR probe molecules.