The nanoscale structural and compositional features of molecular beam epitaxy (MBE)-grown GaAs1−yBiy films have been successfully characterized with unprecedented precision by researchers of the Wisconsin MRSEC using high-resolution x-ray diffractometry and high-resolution high-angle annular dark field (HAADF or “Z-contrast”) imaging in a scanning transmission electron microscope. The spots on the left side of the paired bright spots in the image below are identified as the Ga

NIPS is a non-equilibrium liquid-liquid phase separation phenomenon used to make polymer membranes through solvent-nonsolvent exchange. Newly developed phase-field simulations allow investigation of coupled mass transfer, flow and thermodynamic instability during processing and the corresponding microstructures that result from variations in film composition and thickness. These simulation tools provide critical insight into the nonequilibrium processing of complex fluids to make architectured, resilient solids and soft materials.

Cytoplasmic flows, bacterial colonies, and algal blooms are ubiquitous examples of active suspensions assembled from self-propelled particles, which internally inject energy into their suspending medium and, at sufficient concentrations, can produce large-scale flows. Linking macroscale material properties of active suspension to their underlying microscopic dynamics is a key challenge to describing these materials.

Objective: Use plasmon-enhanced photochemical reactions to map the polarization-dependent near fields of optical antennas. Approach: Use the anisotropic nano-crescent structure and SU-8 photo-resist. SU-8 exposure accomplished through plasmon-enhanced multi-photon absorption by 800 nm light.  Approach: Use the anisotropic nano-crescent structure and SU-8 photo-resist. SU-8 exposure accomplished through plasmon-enhanced multi-photon absorption by 800 nm light. 

Automated Particle-Resolved Colloidal Characterization  

Metallic glass nanostructures provide a new platform for electrocatalytic applications. Several surface modification strategies that remove or add metal species (images, right) improve the catalytic activity of metallic glass nanostructures.   These strategies were demonstrated for three key electrocatalytic reactions important for renewable energy.     

  By fabricating graphene structures atop nanometer-scale “steps” etched into silicon carbide, researchers have for the first time created a substantial electronic bandgap in the material suitable for room-temperature electronics. Use of nanoscale topography to control the properties of graphene could facilitate fabrication of transistors and other devices, potentially opening the door for developing all-carbon integrated circuits.

Semiconductor nanocrystals hold great potential for the low-cost manufacture of electronic devices. 

Doping semiconductor nanocrystals with transition metals is an efficient route to tune emission color over a broad range of wavelengths. We have developed a simple and environmentally friendly process for protein-aided mineralization of transition metal doped ZnS nanocrystals. Biofabricated ZnS:Mn quantum dots (QDs)