Dynamic Liquid-like Membrane Gates Mass Transport in Inorganic Nanocells.

Abstract

Interactive "visualization-manipulation" of membrane-regulated behavior with high spatiotemporal resolution remains challenging. Here, we in situ design and visualize inorganic nanocells from an exciting cinnabar semiconductor while simultaneously forming liquid-like membranes and Hg nanodroplets. A full picture of such membranes from birth to disappearance, including membrane-associated gating of mass transport either in a single nanocell or across multiple nanocells, is revealed at the atomic scale. Periodic reversible cross-feeding occurs among nanodroplets confined in a single nanocell, preventing the release of Hg-associated species to the surroundings. However, once the ionic balance of membranes is disturbed by nanobubbles or electrolytes, the nanodroplets collapse. The released species experience cell-to-cell transport over long distances through nanochannels and are crystallized into Hg(I/II) compounds. Ab initio molecular dynamics simulations suggest that the nanodroplet-membrane interface undergoes dynamic charge fluctuations, recognizing membrane-regulated mass transport in nanoconfined systems. The flexible membrane is stabilized through the balance between Hg atoms and ions, which can be destroyed by nanobubbles.