Zirconium disulfide is a member of the transition metal dichalcogenide family and has shown potential in fields such as field-effect transistors, sensors, and laser fiber fabrication. While liquid-phase exfoliation is considered a simple and low-cost method for producing ZrS2 nanosheets, the common use of toxic organic solvents has hindered its widespread adoption. Additionally, the overall exfoliation yield in these traditional methods remains relatively low. The new approach aims to overcome these barriers by replacing harmful solvents with safer, water-based ionic liquid solutions.

The research team successfully exfoliated bulk ZrS2 into single and few-layer nanosheets using a simple and efficient process. They employed a series of water-imidazolium-based ionic liquids, including [C14mim]Br, [C14mim][C8H7O3], [C14mim][CHN4], [C14mim][C6H4N3], and [C14mim][C8H10NO2]. Among these, the method achieved a maximum exfoliation yield of 82.5 percent. This high yield indicates that the ionic liquid environment is particularly effective at separating the layers of bulk ZrS2 into usable nanosheets.

The study revealed that the exfoliation yield is inversely related to the pKa of the ionic liquid anions. Specifically, the yield decreased as the pKa of the anions increased, suggesting that the chemical properties of the anion play a crucial role in the efficiency of the process. The resulting ZrS2 nanosheets exhibited a thickness of 1 to 2 nanometers and a lateral dimension of 100 to 200 nanometers.

The high exfoliation yield is primarily attributed to strong interactions between the C=O or C–OH groups present in the ionic liquid anions and the ZrS2 structure. These interactions effectively weaken the van der Waals forces that hold the layers of bulk ZrS2 together. Under the assistance of ultrasound, these weakened forces allow for the efficient separation of the layers into individual nanosheets. This mechanism explains the high yield observed in the ionic liquid method.

Beyond the production of high-quality nanosheets, the researchers also evaluated the electrocatalytic properties of the exfoliated material. The prepared ZrS2 nanosheets were applied in the hydrogen evolution reaction as electrocatalysts. The results demonstrated that the nanosheets exhibited stronger electrocatalytic activity compared to bulk ZrS2.

The study highlights the potential of ionic liquids as a versatile tool for the exfoliation of layered materials. By tuning the chemical properties of the ionic liquid anions, researchers can optimize the exfoliation yield and the quality of the resulting nanosheets. The green nature of the exfoliation method, which uses water-based ionic liquids instead of toxic organic solvents, further enhances its appeal for sustainable manufacturing processes.

In conclusion, the development of a high-yield and efficient liquid-phase exfoliation method for ZrS2 using aqueous imidazolium-based ionic liquids represents a significant advancement in materials science. The method produces nanosheets with stronger electrocatalytic properties than the bulk material and offers a safer alternative to traditional exfoliation techniques. This work has great potential in the large-scale production of ZrS2 nanosheets for high-activity hydrogen evolution reactions.

Subject of Research: Liquid-phase exfoliation of zirconium disulfide nanosheets using ionic liquids

Article Title: High-quality and efficient liquid phase exfoliation of zirconium disulfide in aqueous imidazolium-based ionic liquid solutions for efficient electrocatalytic hydrogen evolution reaction

Article References: Li, Y., Song, T., Wang, Z., Li, Z., Zhu, G., & Wang, H. (2026). High-quality and efficient liquid phase exfoliation of zirconium disulfide in aqueous imidazolium-based ionic liquid solutions for efficient electrocatalytic hydrogen evolution reaction. Journal of Materials Science. https://doi.org/10.1007/s10853-026-13941-z

Image Credits: AI Generated

DOI: 10.1007/s10853-026-13941-z

Keywords: zirconium disulfide, nanosheets, ionic liquids, exfoliation, electrocatalysis, hydrogen evolution, materials science, green chemistry, High-quality, efficient, liquid, phase