Pyrrolo[3,2-b]pyrrole-based Anodically Coloring Molecules
Disciplines
Materials Chemistry | Organic Chemistry
Abstract (300 words maximum)
Color control is a helpful tool to have when manufacturing aesthetically-pleasing smart-glass windows. At the press of a button, a voltage can be applied to color-changing materials, or electrochromes, and the glass can either lighten or darken. Here, dihydropyrrolopyrrole (DHPP) is being utilized for its redox-active, electrochromic properties. These electrochromic properties are being modified and analyzed by changing the groups attached to the DHPP. 3 molecules were made: one with a tolyl group and one with a benzotrifluoride group attached to the 2-5 positions of the pyrrolopyrrole scaffold. Additionally, DHPP was modified by way of replacing phenyl units with a heterocycle (in this case pyridine) on the 2,5-positions. UV-vis absorbance spectra of each compound with varying levels of oxidant present were collected and used to understand optical properties with increasing levels of doping. Cyclic voltammetry and differential pulse voltammetry were used to study electrochemical properties and processes each of the three DHPP molecules display. In their oxidized states, tolyl-DHPP and CF3-DHPP exhibited a green color while Pyridine-DHPP exhibited a yellow color. Combined, the different colors that the DHPP molecules exhibit demonstrates that color control can be achieved using the DHPP scaffold. The overall results from this work demonstrates potential applicability of DHPP chromophores as low oxidation potential, high-contrast electrochromes that may serve as materials useful in energy-saving applications.
Academic department under which the project should be listed
Chemistry/Biochemistry
Primary Investigator (PI) Name
Graham S. Collier
Pyrrolo[3,2-b]pyrrole-based Anodically Coloring Molecules
Color control is a helpful tool to have when manufacturing aesthetically-pleasing smart-glass windows. At the press of a button, a voltage can be applied to color-changing materials, or electrochromes, and the glass can either lighten or darken. Here, dihydropyrrolopyrrole (DHPP) is being utilized for its redox-active, electrochromic properties. These electrochromic properties are being modified and analyzed by changing the groups attached to the DHPP. 3 molecules were made: one with a tolyl group and one with a benzotrifluoride group attached to the 2-5 positions of the pyrrolopyrrole scaffold. Additionally, DHPP was modified by way of replacing phenyl units with a heterocycle (in this case pyridine) on the 2,5-positions. UV-vis absorbance spectra of each compound with varying levels of oxidant present were collected and used to understand optical properties with increasing levels of doping. Cyclic voltammetry and differential pulse voltammetry were used to study electrochemical properties and processes each of the three DHPP molecules display. In their oxidized states, tolyl-DHPP and CF3-DHPP exhibited a green color while Pyridine-DHPP exhibited a yellow color. Combined, the different colors that the DHPP molecules exhibit demonstrates that color control can be achieved using the DHPP scaffold. The overall results from this work demonstrates potential applicability of DHPP chromophores as low oxidation potential, high-contrast electrochromes that may serve as materials useful in energy-saving applications.