I. N₂ fixation to NH₃ as well as other nitrogen-containing compounds

Motivation:

Nitrogen atoms are essential component of fertilizers and medicaments. The fixation of the stable dinitrogen molecules under mild conditions has been a long-sought-after goal in chemistry considering the critical need to reduce the energy consumption and carbon dioxide emission.

Our work:

Ø To develop metal hydrides as efficient catalysts for N₂ fixation under mild conditions;

Ø To study the reaction mechanism of N₂ reduction and hydrogenation by metal hydrides;

Ø To study the photochemical and electrochemical properties of metal hydrides for more efficient N₂ fixation processes driven by renewable energy.

Representative publications：

1. Breaking scaling relations to achieve low-temperature ammonia synthesis through LiH-mediated nitrogen transfer and hydrogenation, Nature Chemistry, 9(1): 64-70, 2017.

Paper link: https://www.nature.com/articles/nchem.2595

The cooperation of transition metal (TM) and LiH can break the TM-exerted scaling relations and creates an energy-efficient pathway that allows NH₃ synthesis under mild conditions.

2. Production of ammonia via a chemical looping process based on metal imides as nitrogen carriers, Nature Energy, 3(12): 1067-1075, 2018.

Paper link: https://www.nature.com/articles/s41560-018-0268-z

Alkali and alkaline earth metal imides can function as nitrogen carriers that mediate ammonia production via a two-step chemical looping process operating under mild conditions.

3. Ternary ruthenium complex hydrides for ammonia synthesis via the associative mechanism, Nature Catalysis, 4: 959–967, 2021.

Paper link: https://www.nature.com/articles/s41929-021-00698-8

The ternary ruthenium complex hydrides Li₄RuH₆ and Ba₂RuH₆, facilitates an associative reaction mechanism for ammonia production from N₂ + H₂ with superior kinetics under mild conditions.

4. Light-driven ammonia synthesis under mild conditions using lithium hydride, Nature Chemistry, 16, 373-379, 2024.

Paper link: https://www.nature.com/articles/s41557-023-01395-8

Lithium hydride is shown to mediate photo-driven N₂ fixation under ambient conditions with a fundamentally different reaction mechanism.

II. Hydrides-mediated transformation of small organic molecules such as alkynes, alkenes, and alkanes

Motivation: The hydrogenation/dehydrogenation, hydrogenolysis, or reforming of alkynes, alkenes, and alkanes are important catalytic processes.

Our work: We are aiming to develop novel and advanced hydride materials for the transformation of these key molecules with high activity and selectivity.

Representative publications：

1. Transition Metal-Free Hydrogenolysis of Anilines to Arenes Mediated by Lithium Hydride, Journal of the American Chemical Society, 144(38): 17441-17448, 2022.

Paper link: https://pubs.acs.org/doi/10.1021/jacs.2c05586?ref=pdf

Lithium hydride (LiH) enables the hydrogenolysis of aniline to benzene and ammonia via a unique pathway in which Li-mediated nucleophilic attack of hydride to the α-sp² C atom of aniline plays an important role.

2. Enabling semihydrogenation of alkynes to alkenes by using a calcium palladium complex hydride, Journal of the American Chemical Society, 143(49): 20891-20897, 2021.

Paper link: https://pubs.acs.org/doi/full/10.1021/jacs.1c09489

The complex palladium hydride such as CaPdH₂ can enable selective hydrogenation of alkynes to alkenes.