Multicolor Electrochromic Devices Based on Molecular Plasmonics

Transcription

1 Multicolor Electrochromic Devices Based on Molecular Plasmonics Grant J. Stec, 1,4 Adam Lauchner, 2,4 Yao Cui, 1,4 Peter Nordlander, 2,3,4 and Naomi J. Halas 1,2,3,4 1 Department of Chemistry, Rice University, Houston, TX, USA 2 Department of Electrical and Computer Engineering, Rice University, Houston, TX, USA 3 Department of Physics and Astronomy, Rice University, Houston, TX, USA 4 Laboratory for Nanophotonics, Rice University Houston, TX, USA Author contributions: These Authors contributed equally to this work. Correspondence and requests for materials should be addressed to N.J.H. ( halas@rice.edu). Figure S1. Multichromic perylene electrochromic device. Full images of the device with electrodes for the images from Figure 1. The top alligator clip is connected to the ITO serving as the working electrode, the bottom-left alligator clip is connected to the Pt frame serving as the counter/reference electrode, and the bottom-right alligator clip is attached to a stand which supports the device. Background RICE logo used with permission from Rice University. 1

2 Figure S2. Multistate switching in a perylene electrochromic device. Absorbance intensity measured at 574 nm (the anion peak wavelength) and 530 nm (the cation monomer peak wavelength), and 500 nm (the cation dimer peak wavelength) continuously through cycling of the three voltage states. 2

3 Figure S3. Cycling Behavior. a, The measured absorbance at 574 nm as a function of time for 4 switching cycles at -3.5 V. b, the on state spectrum recorded at t = 5 seconds for each cycle (at -3.5 V, just before switching off). c, the off state spectrum recorded at t = 65 seconds for each cycle (at 0 V, just before switching on the next cycle). The consistency of the off spectra and their similarity to the on spectra demonstrates that no byproduct signal has been unintentionally subtracted from Figure 4. 3

4 Current (A) Current (A) electrode device 2 electrode device Voltage (V) Figure S4. Perylene Cyclic Voltammetry. A two-electrode (Pt, ITO) cyclic voltammogram, and a 3- electrode (Pt, Pt, ITO) cyclic voltammogram for the perylene ion gel electrochromic device. For the 2- electrode device, the Pt-frame counter electrode serves as the reference. For the 3-electrode device, a 2 nd Pt electrode on the same plane as the counter electrode serves as the reference. In both cases, ITO is the working electrode which is separated by the ion gel and double-sided tape/spacer (~120 µm thick) from the counter/reference electrodes. In the 3-electrode device, the ~3.3 V peak is not observed, suggesting that it is actually reduction occurring at the counter-electrode in the 2-electrode measurement. The 2- electrode potentials are reported relative to the Pt-counter electrode; this is consistent with the voltages reported within the body of the paper. The 3-electrode potentials are reported relative to a secondary Pt electrode on the same plane as the Pt-frame counter electrode but electrically isolated from it; the measured voltages have been shifted by 0.25 V (to approximately match the 0 V position of the 2-electrode device) and doubled (to provide the full cell potential). 4

5 Normalized Absorption Perylene Cation (Monomer) Perylene Cation Dimer, d = 3.5 Å Perylene Cation Dimer, d = 3.0 Å Perylene Cation Dimer, d = 2.5 Å d Wavelength (nm) Figure S5. Cation Electronic Spectra. The TDDFT electronic spectra (without plasmon-phonon coupling) for the cation monomer, and the cation dimer with varying distance between the two molecules of the dimer. All calculations are in THF; each molecule in the dimer is positively charged so the total charge of the dimer is +2. The inset shows the arrangement of the dimer used for the calculation, where d denotes the separation distance between the two molecules. The 3 Å separated dimer exhibits a 0.12 ev blueshift from the monomer which agrees well with both the 0.14 ev peak separation observed experimentally (Main Text Figure 2, cation peaks at 530 nm and 500 nm, 2.34 ev and 2.48 ev respectively) and the intermolecular separation distance found from previous dimerization studies. 1 A 3 Å separation also agrees with previous analysis of the perylene cation dimer separation. 5

6 Figure S6. Transmissive-to-black electrochromic device. Full images of the device with electrodes for the images from Figure 5. Background RICE logo used with permission from Rice University. 6

7 Absorbance (arb. u.) Benzo[a]pyrene Anion, 580 nm Anthracene Anion, 720 nm Time (min.) Figure S7. Transmissive-to-black Cycling Behavior. On and off cycle of the transmissive-to-black device when applying -4 V for 5 minutes, then switching to 0 V. Absorbance values are plotted at the peak wavelengths of the benzo[a]pyrene and anthracene anions, 580 and 720 nm, respectively. The spectrometer saturates when the absorbance exceeds 3 units (0.1% transmittance) resulting in the maximum value of 3. The images and transmittance spectrum in Fig. 5 a and c were recorded at 3 min., and the CIELAB chromaticity values reported in the main text were calculated using the spectrum recorded at 3 min. 7

8 Current (A) Black Device (Anthracene +Benzo[a]pyrene) Anthracene-only Device Benzo[a]pyrene-only Device Voltage (V) Figure S8. Two-electrode Cyclic Voltammetry. Two-electrode (Pt, ITO) cyclic voltammogram for devices containing anthracene (blue), benzo[a]pyrene (red), and both PAHs in a single device (black). For the two-electrode measurements a single Pt window on glass is used as both the counter and pseudoreference electrode. Anthracene is reduced at a (full-cell) device voltage of V and benzo[a]pyrene at V. 8

9 REFERENCES 1. Kimura, K., Yamazaki, T. & Katsumata, S. Dimerization Of The Perylene And Tetracene Radical Cations And Electronic Absorption Spectra Of Their Dimers. J. Phys. Chem. 75, (1971). 9