Graphdiyne Enabled Nitrogen Vacancy Formation in Copper Nitride for Efficient Ammonia Synthesis

Zixuan Zhang; Xueting Feng; Zedong Zhang; Long Chen; Wen Liu; Lianming Tong; Xin Gao; Jin Zhang

doi:10.1021/jacs.4c04985

Graphdiyne Enabled Nitrogen Vacancy Formation in Copper Nitride for Efficient Ammonia Synthesis

J Am Chem Soc. 2024 May 29;146(21):14898-14904. doi: 10.1021/jacs.4c04985. Epub 2024 May 15.

Authors

Zixuan Zhang^{1

2}, Xueting Feng^{1

2}, Zedong Zhang³, Long Chen⁴, Wen Liu⁴, Lianming Tong¹, Xin Gao², Jin Zhang^{1

2}

Affiliations

¹ Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P.R. China.
² School of Materials Science and Engineering, Peking University, Beijing 100871, P. R. China.
³ Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
⁴ College of Environmental Sciences and Engineering, The Key Laboratory of Water and Sediment Sciences (Ministry of Education), Peking University, Beijing 100871, P.R. China.

PMID: 38749059
DOI: 10.1021/jacs.4c04985

Abstract

The electrocatalytic reduction of nitrate is promising for sustainable ammonia synthesis but suffers from slow reduction kinetics and multiple competing reactions. Here, we report a catalyst featuring copper nitride (Cu₃N) anchored on a novel graphdiyne support (termed Cu₃N/GDY), which is used for electrocatalytic reduction of nitrate to produce ammonia. The GDY absorbed hydrogen and enabled nitrogen (N) vacancy formation in Cu₃N for the fast nitrate reduction reaction (NO₃RR). Further, the distinct absorption sites formed by GDY and N vacancy enabled the excellent selectivity and stability of NO₃RR. Notably, the Cu₃N/GDY catalyst achieved a high ammonia yield (Y_NH3) up to 35280 μg h^-1 mg_cat.^-1 and a high Faradaic efficiency (FE) of 98.1% using 0.1 M NO₃^- at -0.9 V versus a reversible hydrogen electrode (RHE). Using electron paramagnetic resonance (EPR) technology and in situ X-ray absorption fine structure (XAFS) spectroscopy measurement, we visualized the N vacancy formation in Cu₃N and electrocatalytic NO₃RR enabled by GDY. These findings show the promise of GDY in sustainable ammonia synthesis and highlight the efficacy of Cu₃N/GDY as a catalyst.