Applications | Environmental TEM
Enhance imaging and analysis with functionalized substrates.
Hummingbird Scientific has made significant breakthroughs in the field of in-situ environmental TEM experiments by developing the first commercially available continuous flow in-situ TEM liquid specimen holder that allows imaging of samples in liquid environments. The microfabricated fluid cells that are designed and fabricated by Hummingbird Scientific also allow the application and measurement of signals to the materials inside the liquid, enabling, for example, in-situ electrochemical measurements.
Dune Sciences recently teamed with Hummingbird Scientific to develop functionalized coatings for the grid consummables that are used inside these liquid specimen holders as well as Hummingbird's gas cell holders. Dune's patented functionalization chemistry enable users to tether or immobilize their samples directly on the membrane windows by matching the surface chemistry to the sample.BENEFITS
Nanoparticle Imaging in Liquid and Gas (air)
One application of functionalized grid surfaces for environmental TEM is the immobilization of nanoparticles for viewing in gaseous or liquid environments. In collaboration with Prof. Jim Hutchison at the University of Oregon, 1.5 nm thiocholine stabilized Au nanoparticles were immobilized onto one membrane of the liquid cell chamber that had been functionalized with carboxylate surface chemistry. The thiocholine ligand stabilizer has a permanent positive charge that electrostatically binds to negative surface charge of the carboxylate. The series of images below (in slide presentation form) shows these nanoparticles in air and in liquid. This slide show also includes two STEM images of 10 nm citrate-stabilized Au NPs immobilized on the functioanlized grid with positiviely charged surface. Future experiments will focus on understanding self-assembly and transformations of these types of materials in different environments. All images were taken using a 300keV FEI Titan TEM with STEM detector.
For more information about environmental TEM and to purchase chips for liquid or gas holders, please contact Hummingbird Scientific . For technical questions regarding selection of surface functionalization, please contact us.