Researchers Use Gold Nanoparticles to Unfold 3-D Structures

Researchers at NC State have developed a technique that uses nanoparticles, nanospheres and nanorods, to trigger shape changes in polymers. These differently shaped nanoparticles exhibit different surface plasmon resonances and will heat when exposed to specific wavelengths of light. When embedded in polymers, this causes the material to heat and change its shape. This work has the potential for use in soft robotics applications like biomedical implants. For more on this work, please see the NC State press release.

Sequential Actuation of Shape-Memory Polymers through Wavelength-Selective Photothermal Heating of Gold Nanospheres and Nanorods

Authors: Sumeet R. Mishra and Joseph B. Tracy, North Carolina State University

Published: June 15, Applied Nano Materials

DOI: 10.1021/acsanm.8b00394

Abstract: Photothermal triggering of shape-memory polymers is an appealing noncontact mode of actuation for responsive materials and soft robotics. Wavelength-selective photothermal triggering of shape recovery is reported in thermoplastic polyurethane shape-memory polymers with embedded gold (Au) nanospheres and nanorods. Light-emitting diodes with wavelengths of 530 and 860 nm matched to the surface plasmon resonances drive selective shape recovery. Wavelength-selective shape recovery enables sequential actuation, as demonstrated in a wavelength-controlled stage with optically controlled height and tilt angle using legs of shape-memory-polymer films with embedded Au nanospheres and nanorods.


New Undergraduate Research Opportunity at Smart Materials Solutions

Smart Material Solutions, Inc. (SMS) is seeking two REU students for 10 week paid summer internships. SMS is a small NC State startup in Raleigh, NC that is developing an advanced nanomanufacturing process called nanocoining. The patented process can seamlessly nanopattern drum molds for roll-to-roll manufacturing hundreds of times faster than competing technologies like electron-beam lithography.

Internship 1: Simulations of optical properties
This student will perform finite different time domain (FDTD) simulations to model and optimize the optical properties of nanostructures. The intern will model anti-reflective coatings as well as light-extraction features for OLED displays and solid-state lighting. This student will also be trained in scanning electron microscopy (SEM) and atomic force microscopy (AFM). Students with a background in optics, modeling, physics, electrical engineering, or a related field are encouraged to apply.

Internship 2: Fabrication, characterization, and lamination of nanostructured films
This intern will imprint nanostructures into polymer films and characterize their optical and wetting properties. The student will also laminate nanostructures onto devices such as a solar cell and smartphone. This student will receive training on several characterization techniques including SEM, AFM, and UV-Vis spectroscopy. SMS prefers a student with a background in materials science, chemical engineering, nanotechnology, or a related field.

For more information, please review this flier. To apply, send your resume to and specify which internship interests you.

Making Metamaterials a Household Name

Metamaterials are artificially structured materials used to control and manipulate light, sound, and many other physical phenomena. They became famous for their use in the creation of an “invisibility cloak”. A recent article in Duke Stories describes the history of metamaterials development and how researchers at Duke are striving to make them a household name. Read more here.

RTNN hosts XRD Symposium

Malvern PANalytical and the RTNN hosted a “Non-ambient X-ray Diffraction (XRD)” workshop at NC State November 8-9. The event brought together 48 attendees from 17 different universities and organizations to explore the research potential of non-ambient diffraction and practical advice for collecting accurate and useful data. On the evening of November 8, attendees learned more about on-going research during a poster session.

The picture shows Dr. Tom Blanton, the executive director of International Centre for Diffraction Data (ICDD), presenting his work on ‘Materials Characterization using the ICDD  PDF-4+’.

RTNN Lunch and Learn at UNC-Chapel Hill

Come learn about unique capabilities that could aid in your research! Over lunch, Roberto Garcia (lab manager of NC State’s Analytical Instrumentation Facility, AIF), Dr. John Muth (director of the NC State Nanofabrication Facility, NNF) and Dr. Mark Walters (director of Duke’s Shared Materials Instrumentation Facility, SMIF) will highlight instrumentation at their respective facilities. The RTNN will provide free lunch to all attendees. This talk will take place at UNC: Chapman Hall, Room 125.