This research explored the photochemical properties of the ceramic alloy: SrxBa(1-x)TiO3. This material is of interest because both SrTiO3 and BaTiO3 are able to split water into hydrogen and oxygen gas when exposed to ultra violet radiation and catalysts based on these materials could someday be used for hydrogen gas synthesis. Samples with a variety of alloy compositions were used to photochemically reduce silver and atomic force microscopy (AFM) was used to determine how much silver was deposited on the surface. The experiments indicated that the maximum photochemical reactivity occurs at a composition near the cubic to tetragonal phase transformation and that this composition is more reactive than either of the pure materials.

AFM image of the Sr0.23Ba0.77TiO3 surface with reduced silver (lighter contrast)

3 m

CMU REU : Materials Research – Summer 2007Greg S. Rohrer, Carnegie Mellon University, DMR 0648976

silver

Photochemical Properties of Ceramic Surfaces, Photochemical Properties of Ceramic Surfaces, Andrew Gamalski, Arizona State UniversityAndrew Gamalski, Arizona State University

CMU REU : Materials Research – Summer 2007Greg Rohrer, Carnegie Mellon University, DMR 0648976

Undergraduates (UG) Students at CMU during summer 2007Undergraduates (UG) Students at CMU during summer 2007

2007 REU students posing after final presentations, presenting research project at symposium, awarded for

best research highlight and attending seminar on “good research practices”,

During summer 2007, 28 UG students were exposed to cutting edge nano- and biomaterials research projects involving chemistry, physics and the engineering of materials. The seven REU-supported students were grouped with others supported by the CMU MRSEC, by the PREM between CMU and FSU/FAMU, and by CMU.

The ten week program began with a campus and housing orientation, project definition, lab safety training, and a good research practices workshop with an ethics overview. After five weeks, all the students presented oral reports on their project goals, progress to date, and plans for the second half of the summer. The summer concluded with final oral reports; each student also produced a research highlight, a written paper and answered a questionnaire.

The internship was also punctuated by additional education activities such as mini-courses taught by our faculty, seminars for professional development and fun activities like a Pittsburgh Pirate baseball game, an award ceremony and a wrap-up picnic to adjourn the 2007 summer program.

HST Research Experience

The objective of our summer curriculum development program for HSTs is to raise the level of awareness about the emerging science of nano- and biomaterials among pre-college students. By working with four teachers, the impact on high school students is multiplied by the sizes of their classes over several years.

This summer Eric Laurenson prepared marble and granite samples for mechanical and structural properties analysis. He constructed triple point and compression apparatus to test those materials in the class room. His report includes lesson plans and provides a list of materials and supplies.

Triple point bending test of marble

CMU REU : Materials Research – Summer 2007Greg Rohrer, Carnegie Mellon University, DMR 0648976

High School Teachers (HST) at CMU during summer 2007High School Teachers (HST) at CMU during summer 2007

Yue Chu (2006 HST participant) trains his peers on Monte Carlo Modeling at the annual HST workshop.

Two-Day HST Workshop

During two days of intensive work (June 22-23 2007) former participants Yue Chu (2006) and Michael Real (2004) instructed other HSTs from Pittsburgh Schools on how to implement material science lesson plans on “Materials for Construction” and “Monte Carlo Modeling” in the classroom. From this experience, additional teachers are able to return to their classroom with an activity that can be included into their curriculum, thus exposing more students to materials science.