Discipline: Nanoscience
Subcategory: Materials Science
Session: 2
Room: Park Tower 8216
Olivia M. Penrose Hamouch - Norfolk State University
Co-Author(s): Dr. Carl E. Bonner , Norfolk State University , Norfolk VA
Recent studies have shown that the dielectric constant of the material several nanometers away from the D/A pair can enhance the rate of the photochemical reactions such as the photodecomposition of P3HT in the presence of a layer with an anisotropic dielectric constant. (1, 2) These hyperbolic metamaterials are composed of alternating thin layers of metallic Au and dielectric MgF2. As an assembly, the dielectric constant is metallic in one direction and resistive in the other directions. To further explore this link between the non-local dielectric constant and the reaction, we have used cyclic voltammetry (3) to observed the rate constant of the simplest chemical reaction, the transfer of an electron from Fe(3+) to Fe(2+) , to monitor the effect of the non-local dielectric environment.
According to Marcus Theory, the rate of a reaction is influenced by the dielectric constant of the material in the vicinity of the electron donor and electron acceptor, most typically between the donor and acceptor. (4) The electron transfer current and potential on Au surfaces have been measured to determine the carrier diffusivity and the rate constant for the electron transfer reaction to and from ferricyanide on a gold surface, and are influenced by the presence of a hyperbolic metamaterial. An increase in the rate constant has been observed for the electron transfer reactions in the vicinity of the metamaterials. Future work will examine the effects of the dielectric constant on the rates of the forward and reverse rate constants from which the overall rate constant is formed.
1) V. N. Peters, T. U. Tumkur, and M. A. Noginov, ‘Control of chemical reactions in the vicinity of hyperbolic metamaterials and metallic surfaces,’ in CLEO: 2014, OSA Technical Digest (online) (Optical Society of America, 2014), paper FM1C.6.
2) V. N. Peters, R. Alexander, D. A. Peters and M. A. Noginov, ‘Study of the effect of the Purcell enhancement factor on the photodegradation of the p3ht polymer,’ 2016 Conference on Lasers and Electro-Optics (CLEO), San Jose, CA, 2016, pp. 1-2.
3) Theory and Application of Cyclic Voltammetry for Measurement of Electrode Reaction Kinetics. R. S. Nicholson, Analytical Chemistry 1965 37 (11), 1351-1355 DOI: 10.1021/ac60230a016
4) Electron transfer reactions in chemistry. Theory and experiment, Rudolph A. Marcus, Rev. Mod. Phys. 65, 599
Funder Acknowledgement(s): This work has been supported by the NSF under award HRD 1646789.
Faculty Advisor: Dr. Carl E. Bonner, cebonner@nsu.edu
Role: I performed all of the research.