1. |
- Svirelis, Justas, 1993, et al.
(author)
-
Stable trapping of multiple proteins at physiological conditions using nanoscale chambers with macromolecular gates
- 2023
-
In: Nature Communications. - 2041-1723 .- 2041-1723. ; 14:1
-
Journal article (peer-reviewed)abstract
- The possibility to detect and analyze single or few biological molecules is very important for understanding interactions and reaction mechanisms. Ideally, the molecules should be confined to a nanoscale volume so that the observation time by optical methods can be extended. However, it has proven difficult to develop reliable, non-invasive trapping techniques for biomolecules under physiological conditions. Here we present a platform for long-term tether-free (solution phase) trapping of proteins without exposing them to any field gradient forces. We show that a responsive polymer brush can make solid state nanopores switch between a fully open and a fully closed state with respect to proteins, while always allowing the passage of solvent, ions and small molecules. This makes it possible to trap a very high number of proteins (500-1000) inside nanoscale chambers as small as one attoliter, reaching concentrations up to 60 gL−1. Our method is fully compatible with parallelization by imaging arrays of nanochambers. Additionally, we show that enzymatic cascade reactions can be performed with multiple native enzymes under full nanoscale confinement and steady supply of reactants. This platform will greatly extend the possibilities to optically analyze interactions involving multiple proteins, such as the dynamics of oligomerization events.
|
|
2. |
- Gugole, Marika, 1993, et al.
(author)
-
Comparison of Electrodeposited and Sputtered Tungsten Trioxide Films for Inorganic Electrochromic Nanostructures
- 2023
-
In: ACS Applied Optical Materials. - : American Chemical Society (ACS). - 2771-9855 .- 2574-0962. ; 1:2, s. 558-568
-
Journal article (peer-reviewed)abstract
- Electrochromic materials and their implementation with structural colors are currently being intensely researched because of their promising applications as non-emissive display devices utilizing ambient light. In particular, several fully inorganic devices that rely on electrochromic tungsten trioxide (WO3) have been presented. For preparing nanoscale films of this material, sputtering is the most established technique, but electrodeposition has recently been shown to be capable of achieving exceptionally high electro-optical modulation contrast without the need for expensive equipment. In this work, we investigate the possibilities of electrodeposited WO3 and present a systematic comparison with sputtered WO3 with respect to performance in electrochromic devices. Importantly, we show that “ultralarge” electro-optical modulation (∼95% change in transmission) is possible for both types of films. However, it is only the sputtered films that enable such high contrast in a stable electrolyte such as LiClO4 in propylene carbonate. The electrodeposited films are less uniform and difficult to make thicker than ∼500 nm. We find no evidence that the electrochromic properties of the electrodeposited WO3 are intrinsically better than those of sputtered WO3. However, the electrodeposited films are much rougher and/or porous on the nanoscale, which increases the switching speed considerably. We conclude that electrodeposited WO3 is mainly useful in applications in which high contrast is not essential while switching speed is. As an example, we present the first electrodeposited WO3 integrated with structural colors by sandwiching the material between two metal films. By electrical control, the reflective colors can then be tuned at least one order of magnitude faster (a few seconds) than previously reported while having fair color quality and without any loss of brightness.
|
|
3. |
- Gugole, Marika, 1993, et al.
(author)
-
Electrochromic Inorganic Nanostructures with High Chromaticity and Superior Brightness
- 2021
-
In: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 21:10, s. 4343-4350
-
Journal article (peer-reviewed)abstract
- The possibility of actively controlling structural colors has recently attracted a lot of attention, in particular for new types of reflective displays (electronic paper). However, it has proven challenging to achieve good image quality in such devices, mainly because many subpixels are necessary and the semitransparent counter electrodes lower the total reflectance. Here we present an inorganic electrochromic nanostructure based on tungsten trioxide, gold, and a thin platinum mirror. The platinum reflector provides a wide color range and makes it possible to "reverse"the device design so that electrolyte and counter electrode can be placed behind the nanostructures with respect to the viewer. Importantly, this makes it possible to maintain high reflectance regardless of how the electrochemical cell is constructed. We show that our nanostructures clearly outperform the latest commercial color e-reader in terms of both color range and brightness.
|
|
4. |
- Gugole, Marika, 1993, et al.
(author)
-
High-Contrast Switching of Plasmonic Structural Colors: Inorganic versus Organic Electrochromism
- 2020
-
In: ACS Photonics. - : American Chemical Society (ACS). - 2330-4022. ; 7:7, s. 1762-1772
-
Journal article (peer-reviewed)abstract
- Plasmonic structural colors have recently received a lot of attention. For many applications there is a need to actively tune the colors after preparing the nanostructures, preferably with as strong changes in the optical response as possible. However, to date, there is a lack of systematic investigations on how to enhance contrast in electrically induced color modulation. In this work we implement electrochromic films with plasmonic metasurfaces and compare systematically organic and inorganic materials, with the primary aim to maximize brightness and contrast in a reflective color display. We show nanostructures with good chromaticity and high polarization-insensitive reflectivity (-90%) that are electrochemically stable in a nonaqueous solvent. Methods are evaluated for reliable and uniform electropolymerization of the conductive polymer dimethylpropylenedioxythiophene (PProDOTMe2) on gold. The resulting organic films are well-described by Lambert-Beer formalism, and the highest achievable contrast is easily determined in transmission mode. The optical properties of the inorganic option (WO3) require full Fresnel models due to thin film interference, and the film thickness must be carefully selected in order to maintain the chromaticity of the metasurfaces. Still, the optimized fully inorganic device reaches the highest contrast of approximately 60% reflectivity change for all primary colors. The switching time is about an order of magnitude faster for the organic films (hundreds of ms). The bistability is very long (hours) for the inorganic devices and comparable for the polymers, which makes the power consumption essentially zero for maintaining the same state. Finally, we show that switching of the primary colors in optimized devices (both organic and inorganic) provides almost twice as high brightness and contrast compared to existing reflective display technologies with RGB subpixels created by color filters.
|
|
5. |
- Gugole, Marika, 1993, et al.
(author)
-
Optimizing electrochromism for plasmonic electronic paper: Inorganic vs organic
- 2019
-
In: International Conference on Metamaterials, Photonic Crystals and Plasmonics. - 2429-1390. ; , s. 760-761
-
Conference paper (peer-reviewed)abstract
- The combination of plasmonic nanostructures and electrochromic materials for dynamic color generation has been of interest in recent years due to the possibility to make reflective displays in full color with extremely low power consumption compared to emissive displays. We show a comparison between two electrochromic materials, tungsten trioxide (inorganic) and PProDOTMe2 (organic), for electrical modulation of the resonantly reflected light from plasmonic nanostructures. The comparison focuses on achievable contrast, switching speed, coloration memory and power consumption.
|
|
6. |
- Gugole, Marika, 1993, et al.
(author)
-
Plasmonic Electronic Paper
- 2021
-
In: International Conference on Metamaterials, Photonic Crystals and Plasmonics. - 2429-1390.
-
Conference paper (peer-reviewed)abstract
- We work on developing reflective displays (electronic paper) in color by combining plasmonic nanostructures and electrochromic materials. The main motivation is to save energy in comparison with emissive displays.
|
|
7. |
- Olsson, Oliver, 1993, et al.
(author)
-
Electrochromic Passive Matrix Display Utilizing Diode-Like Redox Reactions on Indium-Tin-Oxide
- 2024
-
In: Advanced Engineering Materials. - 1527-2648 .- 1438-1656. ; 26:8
-
Journal article (peer-reviewed)abstract
- Recent years have shown many advances in the development of tunable structural colors by combining nanostructures with electrochromic materials. One main goal is to develop energy saving color displays that rely on ambient light instead of being emissive. However, all displays need to be pixelated to show arbitrary images and few studies have addressed the challenge of preparing and controlling individual electrochromic pixels. Herein, a very simple method to reach this milestone by using passive matrix addressing is presented, which requires no additional electronic components in the pixels. It is shown that the common transparent conductor indium tin oxide (ITO) in non-aqueous electrolytes exhibits the diode-like behavior (threshold in voltage in relation to current and coloration) necessary to prevent significant cross-talk between pixels. The chemical nature of the redox activity that enables this behavior is attributed to omnipresent oxygen and the formation of superoxide ions. Additionally, it is shown that a gel-like electrolyte can be prepared by optical lithography, which makes the concept compatible with patterning of pixels at high resolution. This method for preparing pixelated displays should be compatible with practically any type of electrochromic surface in both reflective and transmissive configurations. Also, the counter electrode maintains excellent transparency since it simply consists of ITO. The results should prove very useful as the research field of tunable structural colors moves from proof-of-concept to real devices. A method for realizing pixelated electrochromic devices using passive matrix addressing is presented. This is achieved simply by using indium-tin-oxide (ITO) as the counter electrode, which creates a diode-like current response in a stable electrolyte.image (c) 2024 WILEY-VCH GmbH
|
|
8. |
- Olsson, Oliver, 1993, et al.
(author)
-
Enhanced electrochromic switching contrast in the blue by 3,4-propylenedioxypyrrole - Implementation on structural colors
- 2023
-
In: Nanophotonics. - : Walter de Gruyter GmbH. - 2192-8614 .- 2192-8606. ; 12:8, s. 1591-1599
-
Journal article (peer-reviewed)abstract
- Recent advances in nanofabrication technologies have enabled new ways to produce structural colors. By combining nanofabrication methods, it is possible to integrate electrochromic materials with the nanostructures, which enable electrical tuning of the colors and thus new types of reflective displays. Previous work has shown high quality colors and high switching contrast in general. However, so far the intensity modulation has always been more limited in the blue. In this work we prepare blue structural colors and synthesize films of an electrochromic polymer (PProDOP) that is optimized for high contrast in this spectral region. A protocol for electropolymerization of PProDOP on gold surfaces is presented. The polymer films are shown to follow Lambert-Beer behavior and can provide up to 75% contrast (difference in transmittivity). On blue nanostructures, the reflectivity can be modulated with a contrast of 50%, which is a considerable improvement in comparison with previous work. The results presented here should be useful for electrochromic or other electro-optical devices operating in the blue spectral region.
|
|
9. |
- Xiong, Kunli, et al.
(author)
-
Video Speed Switching of Plasmonic Structural Colors with High Contrast and Superior Lifetime
- 2021
-
In: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 33:41
-
Journal article (peer-reviewed)abstract
- Reflective displays or "electronic paper" technologies provide a solution to the high energy consumption of emissive displays by simply utilizing ambient light. However, it has proven challenging to develop electronic paper with competitive image quality and video speed capabilities. Here, the first technology that provides video speed switching of structural colors with high contrast over the whole visible is shown. Importantly, this is achieved with a broadband-absorbing polarization-insensitive electrochromic polymer instead of liquid crystals, which makes it possible to maintain high reflectivity. It is shown that promoting electrophoretic ion transport (drift motion) improves the switch speed. In combination with new nanostructures that have high surface curvature, this enables video speed switching (20 ms) at high contrast (50% reflectivity change). A detailed analysis of the optical signal during switching shows that the polaron formation starts to obey first order reaction kinetics in the video speed regime. Additionally, the system still operates at ultralow power consumption during video speed switching (<1 mW cm(-2)) and has negligible power consumption (<1 mu W cm(-2)) in bistability mode. Finally, the fast switching increases device lifetime to at least 10(7) cycles, an order of magnitude more than state-of-the-art.
|
|
10. |
- Brooke, Robert, 1989-, et al.
(author)
-
All-Printed Multilayers and Blends of Poly(dioxythiophene) Derivatives Patterned into Flexible Electrochromic Displays
- 2023
-
In: Macromolecular materials and engineering. - : John Wiley and Sons Inc. - 1438-7492 .- 1439-2054. ; 308:2
-
Journal article (peer-reviewed)abstract
- Low-cost, flexible and thin display technology is becoming an interesting field of research as it can accompany the wide range of sensors being developed. Here, the synthesis of poly(dimethylpropylene-dioxythiophene) (PProDOT-Me2) by combining vapor phase polymerization and screen printing is presented. A multilayer architecture using poly(3,4-ethylenedioxythiophene) (PEDOT) and PProDOT-Me2 to allow for electrochromic switching of PProDOT-Me2, thereby eliminating the need for a supporting transparent conductive (metal oxide) layer is introduced. Furthermore, the technology is adapted to a blended architecture, which removes the additional processing steps and results in improved color contrast (∆E* > 25). This blend architecture is extended to other conductive polymers, such as PEDOT and polypyrrole (PPy), to highlight the ability of the technique to adjust the color of all-printed electrochromic displays. As a result, a green color is obtained when combining the blue and yellow states of PEDOT and PPy, respectively. This technology has the potential to pave the way for all-printed multicolored electrochromic displays for further utilization in printed electronic systems in various Internet of Things applications. © 2022 The Authors.
|
|