H_(aq)~+ Structures in Proton Wires inside Nanotubes

摘要

Nanoscale science focuses attention on how bulk properties are altered when substances are confined to small spaces and reduced dimensionality. For example, theory suggests that water takes on novel "ice" structures when confined inside carbon nanotubes. Calculations also support the idea that confinement of H_(aq)~+ to narrow channels creates a proton wire having up to 40 times faster proton transport than in the bulk. These findings are relevant to proton mobility in nanoscale channels of fuel-cell membranes and also to biological proton transport, where chains of water molecules are found in channels of transmembrane proteins involved in proton pumping and cellular pH control.