TY - JOUR
T1 - Achieving Low-Energy Driven Viologens-Based Electrochromic Devices Utilizing Polymeric Ionic Liquids
AU - Lu, Hsin Che
AU - Kao, Sheng Yuan
AU - Yu, Hsin Fu
AU - Chang, Ting Hsiang
AU - Kung, Chung Wei
AU - Ho, Kuo Chuan
N1 - Funding Information:
We would like to thank the Ministry of Science and Technology (MOST) of Taiwan for the financial support under grant numbers 104-2221-E-002-127-MY2 and 105-ET-E- 002-003-ET. We would like to thank Professor Man-kit Leung in the Department of Chemistry, National Taiwan University, for the help with the NMR analysis.
Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/11/9
Y1 - 2016/11/9
N2 - Herein, three kinds of viologens-based electrochromic devices (ECDs) (heptyl viologen (HV(BF4)2), octyl viologen (OV(BF4)2), and nonyl viologen (NV(BF4)2)) were fabricated utilizing ferrocene (Fc) as a redox mediator. Among them, the NV(BF4)2-based ECD exhibits the highest coloration efficiency (36.2 cm2/C) owing to the lowest driving energy. Besides, switching between 0 and 1.2 V, the NV(BF4)2-based ECD shows a desirable initial transmittance change (δT = 56.7% at 605 nm), and long-term stability (δT = 45.4% after 4000 cycles). Furthermore, a UV-cured polymer electrolyte containing polymeric ionic liquid (PIL, 1-allyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) and ethoxylated trimethylolpropane triacrylate (ETPTA) was introduced to the NV(BF4)2-based ECD. By controlling the weight percentage of the PIL, different curing degrees of the polymer electrolytes were obtained and led to an improved stability of the NV(BF4)2-based ECD because of the immobilization of NV(BF4)2. This observation was explained by calculating the apparent diffusivity (Dapp) of the redox species in the NV(BF4)2-based ECD under various curing degrees. In addition, increasing the amount of PIL leads to a lower driven energy needed for the NV(BF4)2-based ECD, following the same trend as the value of Dapp. Among all NV(BF4)2-based ECDs, 20 wt % of PIL addition (20-PIL ECD) exhibits large transmittance change (δT = 55.2% at 605 nm), short switching times (2.13 s in coloring and 2.10 s in bleaching), high coloration efficiency (60.4 and 273.5 cm2/C at 605 nm, after excluding the current density at the steady state), and exceptional cycling stability (δT = 53.8% after 10,000 cycles, or retained 97.5% of its initial δT).
AB - Herein, three kinds of viologens-based electrochromic devices (ECDs) (heptyl viologen (HV(BF4)2), octyl viologen (OV(BF4)2), and nonyl viologen (NV(BF4)2)) were fabricated utilizing ferrocene (Fc) as a redox mediator. Among them, the NV(BF4)2-based ECD exhibits the highest coloration efficiency (36.2 cm2/C) owing to the lowest driving energy. Besides, switching between 0 and 1.2 V, the NV(BF4)2-based ECD shows a desirable initial transmittance change (δT = 56.7% at 605 nm), and long-term stability (δT = 45.4% after 4000 cycles). Furthermore, a UV-cured polymer electrolyte containing polymeric ionic liquid (PIL, 1-allyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) and ethoxylated trimethylolpropane triacrylate (ETPTA) was introduced to the NV(BF4)2-based ECD. By controlling the weight percentage of the PIL, different curing degrees of the polymer electrolytes were obtained and led to an improved stability of the NV(BF4)2-based ECD because of the immobilization of NV(BF4)2. This observation was explained by calculating the apparent diffusivity (Dapp) of the redox species in the NV(BF4)2-based ECD under various curing degrees. In addition, increasing the amount of PIL leads to a lower driven energy needed for the NV(BF4)2-based ECD, following the same trend as the value of Dapp. Among all NV(BF4)2-based ECDs, 20 wt % of PIL addition (20-PIL ECD) exhibits large transmittance change (δT = 55.2% at 605 nm), short switching times (2.13 s in coloring and 2.10 s in bleaching), high coloration efficiency (60.4 and 273.5 cm2/C at 605 nm, after excluding the current density at the steady state), and exceptional cycling stability (δT = 53.8% after 10,000 cycles, or retained 97.5% of its initial δT).
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U2 - 10.1021/acsami.6b10152
DO - 10.1021/acsami.6b10152
M3 - Article
AN - SCOPUS:84994745337
SN - 1944-8244
VL - 8
SP - 30351
EP - 30361
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 44
ER -