Richard M. Crooks
  University of Texas at
  Austin

http://research.cm.utexas.edu/rcrooks/
Richard M. Crooks received his BS degree from The University of Illinois at Urbana-Champaign in 1981 working under the direction of Dr. Larry R. Faulkner. He graduated with a Ph.D. from The University of Texas at Austin in 1987 working under the direction of Dr. Allen J. Bard specializing in electrochemistry. After completing postdoctoral work at MIT (1987-1989), Crooks started his teaching career as an Assistant Professor at the University of New Mexico from 1989 – 1993. He later transferred to Texas A&M becoming an Associate Professor from 1993-1997 with a promotion to full Professor from 1997-2005. During his time at A&M, Crooks was the founding director of the Center for Integrated Microchemical Systems. Currently, Crooks is a Professor of Chemistry at UT hosting a group of approximately 10 graduate students, three postdoctoral fellows and two undergraduates. The Crooks group has broad interests in electrochemistry, biological and chemical microsensors, and nanomaterials. At present, projects are focused in two areas: (1) synthesis and characterization of highly selective nanocomposite catalysts, (2) design and fabrication of a new family of sensors based on micro- and nanofluidic devices.

Department Lecture Series
Thursday Oct. 11, 9:45 am, Smith 331

Synthesis, Characterization, and Electrocatalytic Applications
of Dendrimer-Encapsulated Nanoparticles


Pt and Pd monometallic and Pt-Pd bimetallic (alloy) nanoparticles containing up to an average of 180 atoms were prepared within sixth-generation, hydroxyl-terminated, poly(amidoamine) dendrimers. Transmission electron microscopy, energy dispersive X-ray spectroscopy (EDS), UV-vis spectroscopy, and EXAFS measurements confirmed that the size and composition of these materials could be precisely controlled. Cyclic voltammetry and rotating disk voltammetry were used to measure the electrocatalytic properties of these materials for the oxygen reduction reaction. Particular compositions of the bimetallic nanoparticles exhibited an enhancement of up to a factor of 2.5 compared to monometallic Pt. However, the most important result of this project is the demonstration that electrocatalysts containing just 180 atoms and having uniform compositions can be synthesized and characterized ex situ and then subsequently be immobilized on an electrode surface. This provides a means to correlate the structure of the nanoparticles to their electrocatalytic function. In contrast, previous studies have relied on electrocatalysts being prepared in situ, which makes it difficult to control and analyze their properties.