Temperature dependence of working pressure of a nanoporous liquid spring

The thermal effect on nanofluidic behaviors in a hydrophobic zeolite is investigated experimentally. At a constant temperature, water can be forced to infiltrate into the nanopores as an external pressure is applied and defiltrate as the pressure is lowered, leading to a springlike pressure-volume relationship. As temperature varies, due to the variation in solid-liquid interfacial tension, the infiltration pressure changes significantly. Consequently, the system exhibits a thermally controllable volume memory characteristic, with the energy density higher than that of ordinary shape-memory solids by more than one order of magnitude, providing a promising way for developing high-performance intelligent devices. (c) 2006 American Institute of Physics.