Professor Allen J. Bard of the University of Texas at Austin is supported by the Analytical and Surface Chemistry program to further applications of the scanning electrochemical microscope (SECM). One area of study is focusing on the development of SECM systems that integrate a micropipet dispensing tip. The integrated system is enabling SECM tip capabilities, such as detection, probe positioning and reagent generation, to be combined with localized picoliter dispensing of solutions. Advances are broadening the scope of SECM applications to include surface patterning, combinatorial electrocatalyst discovery and spatial mapping of biologically active species. Another area of investigation involves probing electrocatalysts in the 1-20 nm range at the level of a single particle. Emphasis is on oxygen reduction and hydrogen oxidation and carrying out measurements of heterogeneous electron transfer rates as functions of particle size. Additional areas of study include fast electron transfer through monolayers on electrodes, charge transport in thin layer films of enzyme "wired" by polymer containing redox active groups that serve as electron transport relays and screening of enzyme biomimetic catalysts for oxygen reduction. For the former, DNA and molecular systems that provide models for molecular wires are of special interest.
Advances being made by the Bard group through applications of the scanning electrochemical microscope are impacting areas of technological importance, such as the field of energy resources through the discovery of new electrocatalysts that can be used in fuel cells and air batteries. The research is also applicable to the development of sensors and new approaches to studies of biological cells at the single cell level.
