A synthetic leaf: The biomimetic potential of graphene oxide

Emerging materials such as graphene oxide (GO) have micro and nano features that are functionally similar to those in plant cell walls involved in water transport. Therefore, it may now be possible to design and build biomimetic trees to lift water via mechanisms similar to those employed by trees, allowing for potential applications such as passive water pumping, filtering, and evaporative cooling. The tallest trees can raise large volumes of water to over 100 meters using only the vapor pressure gradient between their leaves and the atmosphere. This phenomenon occurs in all terrestrial plants when capillary forces generated in the microscopic pores in the cell walls of leaves are collectively applied to large diameter xylem conduits. The design of a synthetic tree that mimics these mechanisms will allow water to be moved to heights greater than is currently possible by any engineered system that does not require the use of a positive pressure pump. We are testing the suitability of membranous GO as the leaf of a synthetic tree and present an analysis in support of this design. In addition, we include results from a preliminary design using ceramics.