Designable Matter: Shape-Shifting Materials for Energy Storage and Conversion

P. Alex Greaney, Ph.D.
Assistant Professor
Department of Mechanical Engineering
University of California, Riverside

This talk will describe an interdisciplinary collaboration to engender a new class of responsive materials that change their shape and porosity by exposure to sunlight. To realize  these  materials  our  team  is  developing  a  design-led  method  for  materials development that allies materials science and engineering design theory in order to systematically invent rather than discover new materials. These materials are able to shape-shift  as  a  result  of  their  molecular  architecture,  which  is  based  on  metal-organic-frameworks  (MOFs),  and  are  designed  to  act  as  a  giant  stochastic  linkage actuated by photoisomerization (light driven shape change). We call these shape-shifting materials MORFs (metal-organic-responsive-frameworks). A major challenge that must be  overcome  is  the  geometric  constraint  that  the  framework  imposes  on  the photoisomerizing actuators. In our approach we are looking beyond this challenge and seek to use constraint to our advantage—enabling us to tune previously immutable properties of the photoisomers such as their energy conversion efficiency. We envision this new material class enabling diverse applications with significant and lasting societal impact  such  as  self-squeezing  hydrogen  sponges,  active  filtration  and  catalysis,  gas separation and CO2 capture, environmental monitoring, and solar energy conversion and storage. This ambitious research collaboration is generously supported by the W.M. Keck Foundation.

Dr. Greaney’s research is focused on using computation and theory to understand the fundamental  structure-property  relationships  in  materials.  His  group’s  research  encompasses  thermal  properties  of  materials,  mechanical  properties,  functional nanostructures materials, and computational design of materials.