The deposit microstructure, i.e. grain orientation and grain boundaries, limits the device performance such as mobility and quantum efficiency. In a recent paper published in APL Materials [1], Randy Headrick and coworkers at the University of Vermont studied the structure formation of the solvable organic semiconductor C8-BTBT.
In previous work in the Dichtel lab from Catherine DeBlase and coworkers, this principle was demonstrated using anthraquinone subunits. However, the electroactive COFs were not oriented. DeBlase found that by slowly introducing the monomer concentration, the COF film thickness can be controlled. Crystalline, oriented thin films were grown on gold working electrodes and analyzed using grazing incidence diffraction (GID) at CHESS’s G2 beamline. The oriented films had 400% improved capacitance compared to that of randomly oriented COF powder.
One of the judges of the competition noted that "This list represents a snapshot of Asia's up-and-coming technologists and innovators. It was a challenge to narrow down 100 names to the 10 you see here."
This new system, known as CHESS-DAQ, consists of a dedicated high-speed network that connects the experimental stations to over 130 terabytes of enterprise-class redundant disk arrays, as well as an offsite magnetic tape library for long-term archival. From September through December 2015, we collected roughly 40 terabytes of data, which is more than a factor of 12 increase over the first run of 2015.
As mentioned in a previous newsletter, our "Junk Genies" program has students transforming underutilized appliances into interactive physics treasure troves for public enjoyment. Last month, the finished exhibits left Ithaca aboard the Ithaca Physics Bus where they've traveled thousands of miles and have been enjoyed by hundreds of visitors.
The course consists of a series of lectures providing the basic background necessary to successfully analyze diffraction data gathered using high-energy X-ray experiments at synchrotron light sources with the goal of understanding the mechanical response of crystalline solids. The successful outcome for students who watch the lectures is developing sufficient comfort with the theory and algorithms underneath X-ray processing tools such that these tools are no longer a "black-box" and students are able to edit tools for their own research needs.
Our goal is to discuss with the user community the scientific needs potentially met by state-of-the-art high-energy, high-flux x-ray beamline capabilities. The science topics cover the gamut from fundamental materials science through biological and engineering materials, with techniques ranging from diffraction and scattering to scanning spectroscopies to wide-dynamic-range diffuse scattering.
The goal of these workshops is to identify science communities needing unique state-of-the-art high-energy, high-flux x-ray beamline capabilities. We hope to engage users about forefront science questions they will need to solve, and how high-performance third-generation capabilities at CHESS can provide solutions.
For example, even when the chemical and/or optical properties of an individual molecule are known, it is often unclear precisely how these properties change the molecule is coerced into a thin, crystalline to fabricate a device. A recent Letter by graduate student Naveen Rawat of the University of Vermont, appearing in The Journal of Physical Chemistry (http://pubs.acs.org/doi/abs/10.1021/acs.jpclett.5b00714) contributes significantly to this challenge.
K D. Finkelsteina,1, R. Jonesb, A. Paulinga, Z. Browna, A. Tarunc, S. Jupitzd, D C. Sagane, D S. Misrac