A joint research team from Drexel University and the Berlin Synchrotron Radiation Center (HZB) has published a significant discovery in Nature Communications, revealing the unique behavior of confined water in the two-dimensional material MXene and its impact on material properties. This study provides a new perspective for understanding the fundamental properties of water at the nanoscale.

The team conducted systematic analysis on MXene samples containing different ions and confined water using the BESSY II synchrotron radiation source. Experimental results showed that water molecules between MXene layers spontaneously form amorphous ice clusters, leading to an increase in interlayer spacing and triggering a transition from metallic to semiconducting properties. HZB scientist Dr. Tristan Petit stated: “When heated above 300 K, the clusters dissolve again, restoring the interlayer distance and the metallic behavior.”

Co-first author Dr. Katherine Mazzio noted: “MXene is an ideal material for studying confined water phase transitions, providing new insights into how water behaves at the nanoscale.” Using various X-ray techniques, the researchers confirmed that the hydrogen bond network formed by water molecules between MXene layers exhibits special properties not observed in conventional bulk water.

As a new class of two-dimensional materials composed of transition metal carbides and nitrides, MXene's layered structure is particularly suitable for studying water behavior in confined environments. The research team stated that the next step will involve computer modeling to further understand the formation mechanism of amorphous ice and its impact on electron transport. These findings not only expand our understanding of the fundamental properties of water but may also promote the application development of MXene in energy storage, catalysis, and other fields.