Ni 2 P active site ensembles tune electrocatalytic nitrate reduction selectivity

Nishiwaki, Emily; Rice, Peter S.; Kuo, Ding-Yuan; Dou, Florence Y.; Pyka, Anthony; Reid, Bryce; Nguyen, Hao A.; Stuve, Eric M.; Raugei, Simone; Cossairt, Brandi M.

doi:10.1039/d4cc01834f

DOE OSTI · 2499515

Ni 2 P active site ensembles tune electrocatalytic nitrate reduction selectivity

Nishiwaki, Emily·Rice, Peter S.·Kuo, Ding-Yuan·Dou, Florence Y.·Pyka, Anthony·Reid, Bryce·Nguyen, Hao A.·Stuve, Eric M.·Raugei, Simone·Cossairt, Brandi M.

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Abstract

Here, we demonstrate that active site ensembles on transition metal phosphides tune the selectivity of the nitrate reduction reaction. Using Ni 2 P nanocrystals as a case study, we report a mechanism involving competitive co-adsorption of H* and NO x * intermediates. A near 100% faradaic efficiency for nitrate reduction over hydrogen evolution is observed at -0.4 V, while NH 3 selectivity is maximized at -0.2 V vs. RHE.

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Nishiwaki, Emily, Rice, Peter S., Kuo, Ding-Yuan, Dou, Florence Y., Pyka, Anthony, Reid, Bryce, Nguyen, Hao A., Stuve, Eric M., Raugei, Simone, Cossairt, Brandi M.. 2024-06-10. Ni 2 P active site ensembles tune electrocatalytic nitrate reduction selectivity. https://doi.org/10.1039/d4cc01834f

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