Intercalation assisted liquid phase production of disulfide zirconium nanosheets for efficient electrocatalytic dinitrogen reduction to ammonia

Abstract

Disulfide zirconium (ZrS₂) is a two-dimensional (2D) transition metal disulfide and has given rise to extensive attention because of its distinctive electronic structure and properties. However, mass production of high quality of ZrS₂ nanosheets to realize their practical application remains a challenge. Here, we have successfully exfoliated the bulk ZrS₂ powder with the thickness of micron into single and few-layer nanosheets through liquid-phase exfoliation in N-methylpyrrolidone (NMP) assisted via aliphatic amines as intercalators. It is found that the exfoliation yield is as high as 27.3%, which is the record value for the exfoliation of ZrS₂ nanosheets from bulk ZrS₂ powder, and 77.1% of ZrS₂ nanosheets are 2–3 layers. The molecular geometric size and aliphatic amine basicity have important impact on the exfoliation. Furthermore, the ZrS₂ nanosheets have been used as catalyst in the electrocatalytic dinitrogen reduction with the NH₃ yield of 57.75 μg h⁻¹ mg_cat.⁻¹, which is twice that by ZrS₂ nanofibers reported in literature and three times that by the bulk ZrS₂ powder. Therefore, the liquid phase exfoliation strategy reported here has great potential in mass production of ZrS₂ nanosheets for high activity electrocatalysis.