A mass transfer system including a housing and a three-dimensional ordered open-cellular micro-truss material within the housing for a mass transfer application. Here, the three-dimensional ordered open-cellular micro-truss material includes a plurality of first truss elements defined by a plurality of first self-propagating polymer waveguides and extending along a first direction, a plurality of second truss elements defined by a plurality of second self-propagating polymer waveguides and extending along a second direction, and a plurality of third truss elements defined by a plurality of third self-propagating polymer waveguides and extending along a third direction. The first, second, and third ordered truss elements interpenetrate each other at a plurality of nodes to form a continuous material. In one embodiment, the continuous material is a metal material.