We have recently demonstrated the ability to control the thermal conductivity of a material derived from squid ring teeth protein by hydrating the material with water. In collaboration with Prof. Melik Demirel’s group at Penn State, along with collaborations from Prof. Ben Allen at Penn State and Dr. Madhusudan Tyagi from NIST and UMN, we have develop a thermal conductivity switch with higher thermal conductivity on/off ratios than any other single material that has been observed to date. Congrats to John Tomko who was a first author on this paper that appeared in Nature Nanotechnology (Tomko, J.A., Pena-Francesch, A., Jung, H., Tyagi, M., Allen, B.D., Demirel, M.C., Hopkins, P.E., “Tunable thermal transport and reversible thermal conductivity switching in topologically-networked bio-inspired materials,” Nature Nanotechnology 13, 959-964 (2018). PDF (Supporting Information).).
Paper information below
Title:
Tunable thermal transport and reversible thermal conductivity switching in topologically networked bio-inspired materials
Abstract
The dynamic control of thermal transport properties in solids must contend with the fact that phonons are inherently broad- band. Thus, efforts to create reversible thermal conductivity switches have resulted in only modest on/off ratios, since only a relatively narrow portion of the phononic spectrum is impacted. Here, we report on the ability to modulate the thermal conductivity of topologically networked materials by nearly a factor of four following hydration, through manipulation of the displacement amplitude of atomic vibrations. By varying the network topology, or crosslinked structure, of squid ring teeth-based bio-polymers through tandem-repetition of DNA sequences, we show that this thermal switching ratio can be directly programmed. This on/off ratio in thermal conductivity switching is over a factor of three larger than the cur- rent state-of-the-art thermal switch, offering the possibility of engineering thermally conductive biological materials with dynamic responsivity to heat.
J.A.T. and P.E.H. acknowledge support from the Office of Naval Research (grant no. N00014-15-12769). M.C.D., B.D.A., A.P.-F. and H.J. were supported by the Army Research Office (grant no. W911NF-16-1-0019) and the Materials Research Institute of Pennsylvania State University. Access to the HFBS was provided by the Center for High Resolution Neutron Scattering, a partnership between the National Science Foundation and NIST under agreement no. DMR-1508249. Certain commercial material suppliers are identified in this paper to foster understanding. Such identification does not imply recommendation or endorsement by the NIST, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.
patrickehopkins.com 
Leave a Reply