Influence of single-nanoparticle electrochromic dynamics on the durability and speed of smart windows

Nanomaterials have tremendous potential to increase electrochromic smart window efficiency, speed, and durability. However, nanoparticles vary in size, shape, and surface defects, and it is unknown how nanoparticle heterogeneity contributes to particle-dependent electrochromic properties. Here, we use single-nanoparticle-level electro-optical imaging to measure structure–function relationships in electrochromic tungsten oxide nanorods. Single nanorods exhibit a particle-dependent waiting time for tinting (from 100 ms to 10 s) due to Li-ion insertion at optically inactive surface sites. Longer nanorods tint darker than shorter nanorods and exhibit a Li-ion gradient that increases from the nanorod ends to the middle. The particle-dependent ion-insertion kinetics contribute to variable tinting rates and magnitudes across large-area smart windows. Next, we quantified how particle–particle interactions impact tinting dynamics and reversibility as the nanorod building blocks are assembled into a thin film. Interestingly, single particles tint 4 times faster and cycle 20 times more reversibly than thin films made of the same particles. These findings allow us to propose a nanostructured electrode architecture that optimizes optical modulation rates and reversibility across large-area smart windows.

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Fabrication of solar and electrically adjustable large area smart windows for indoor light and heat modulation

Journal of Materials Chemistry C ◽

10.1039/c7tc01489a ◽

2017 ◽

Vol 5 (24) ◽

pp. 5917-5922 ◽

Cited By ~ 16

Author(s):

Ashutosh K. Singh ◽

S. Kiruthika ◽

Indrajit Mondal ◽

Giridhar U. Kulkarni

Keyword(s):

Smart Window ◽

Large Area ◽

Smart Windows ◽

Active Layers ◽

Window Applications

Invisible Cu mesh electrodes used as ITO alternative serve as transparent heaters for large area smart window applications with commercial thermochromic pigments and gels as active layers.

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High-Efficiency Responsive Smart Windows Fabricated by Carbon Nanotubes Modified by Liquid Crystalline Polymers

Crystals ◽

10.3390/cryst11040440 ◽

2021 ◽

Vol 11 (4) ◽

pp. 440

Author(s):

Yuan Deng ◽

Shi-Qin Li ◽

Qian Yang ◽

Zhi-Wang Luo ◽

He-Lou Xie

Keyword(s):

Carbon Nanotubes ◽

Liquid Crystalline ◽

Near Infrared ◽

High Efficiency ◽

Polymer Brush ◽

Light Transmittance ◽

Smart Window ◽

Vertical Orientation ◽

Smart Windows ◽

Conversion Materials

Smart windows can dynamically and adaptively adjust the light transmittance in non-energy or low-energy ways to maintain a comfortable ambient temperature, which are conducive to efficient use of energy. This work proposes a liquid crystal (LC) smart window with highly efficient near-infrared (NIR) response using carbon nanotubes grafted by biphenyl LC polymer brush (CNT-PDB) as the orientation layer. The resultant CNT-PDB polymer brush can provide the vertical orientation of LC molecules to maintain the initial transparency. At the same time, the smart window shows a rapid response to NIR light, which can quickly adjust the light transmittance to prevent sunlight from entering the room. Different from common doping systems, this method avoids the problem of poor compatibility between the LC host and photothermal conversion materials, which is beneficial for improving the durability of the device.

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Strong texture tuning along different crystalline directions in glass-supported CeO2 thin films by ultrasonic spray pyrolysis

Scientific Reports ◽

10.1038/s41598-021-81353-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Inti Zumeta-Dubé ◽

José Manuel García Rangel ◽

Jorge Roque ◽

Issis Claudette Romero-Ibarra ◽

Mario Fidel García Sánchez

Keyword(s):

Thin Films ◽

Spray Pyrolysis ◽

Spray Pyrolysis Technique ◽

Morphological Characteristics ◽

Ultrasonic Spray Pyrolysis ◽

Cost Effective ◽

Growth Direction ◽

Large Area ◽

Smart Windows ◽

Ultrasonic Spray

AbstractThe strong facet-dependent performance of glass-supported CeO2 thin films in different applications (catalysis, smart windows, etc.) has been the target of diverse fundamental and technological approaches. However, the design of accurate, cost-effective and scalable methods with the potential for large-area coverage that produce highly textured glass-supported CeO2 thin films remains a technological challenge. In the present work, it is demonstrated that under proper tuning conditions, the ultrasonic spray pyrolysis technique enables one to obtain glass-supported polycrystalline CeO2 films with noticeable texture along both the (100) and (111) directions, as well as with randomly oriented crystallites (no texture). The influence of flow rates, solution molarity, and substrate temperature on the texture and morphological characteristics, as well as optical absorption and Raman response of the deposited films, is evaluated. The obtained results are discussed on the basis of the combined dependence of the CeO2-exposed surfaces on the thermodynamic stability of the corresponding facets and the reaction kinetics, which modulate the crystallite growth direction.

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Full-frame and high-contrast smart windows from halide-exchanged perovskites

Nature Communications ◽

10.1038/s41467-021-23701-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

You Liu ◽

Jungan Wang ◽

Fangfang Wang ◽

Zhengchun Cheng ◽

Yinyu Fang ◽

...

Keyword(s):

Contrast Ratio ◽

High Contrast ◽

Smart Window ◽

Frame Size ◽

Smart Windows ◽

Ideal Solutions ◽

Ion Gel ◽

And Control ◽

Colour Rendering ◽

Perovskite Photovoltaic

AbstractWindow glazing plays an essential role to modulate indoor light and heat transmission, which is a prospect to save the energy cost in buildings. The latest photovoltachromic technology has been regarded as one of the most ideal solutions, however, to achieve full-frame size (100% active area) and high-contrast ratio (>30% variable in visible wavelength) for smart window applicability is still a challenge. Here we report a photovoltachromic device combining full-transparent perovskite photovoltaic and ion-gel based electrochromic components in a vertical tandem architecture without any intermediated electrode. Most importantly, by accurately adjusting the halide-exchanging period, this photovoltachromic module can realize a high pristine transmittance up to 76%. Moreover, it possesses excellent colour-rendering index to 96, wide contrast ratio (>30%) on average visible transmittance (400-780 nm), and a self-adaptable transmittance adjustment and control indoor brightness and temperature automatically depending on different solar irradiances.

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Interaction-tailored organization of large-area colloidal assemblies

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.150 ◽

2018 ◽

Vol 9 ◽

pp. 1582-1593 ◽

Cited By ~ 4

Author(s):

Silvia Rizzato ◽

Elisabetta Primiceri ◽

Anna Grazia Monteduro ◽

Adriano Colombelli ◽

Angelo Leo ◽

...

Keyword(s):

Film Formation ◽

Low Cost ◽

Interparticle Distance ◽

Particle Interactions ◽

Polystyrene Spheres ◽

Large Area ◽

Nanoscale Patterning ◽

Particle Solution ◽

Number Of Particles ◽

Deposition Conditions

Colloidal lithography is an innovative fabrication technique employing spherical, nanoscale crystals as a lithographic mask for the low cost realization of nanoscale patterning. The features of the resulting nanostructures are related to the particle size, deposition conditions and interactions involved. In this work, we studied the absorption of polystyrene spheres onto a substrate and discuss the effect of particle–substrate and particle–particle interactions on their organization. Depending on the nature and the strength of the interactions acting in the colloidal film formation, two different strategies were developed in order to control the number of particles on the surface and the interparticle distance, namely changing the salt concentration and absorption time in the particle solution. These approaches enabled the realization of large area (≈cm2) patterning of nanoscale holes (nanoholes) and nanoscale disks (nanodisks) of different sizes and materials.

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A Large-Area Smart Window with Tunable Shading and Solar-Thermal Harvesting Ability Based on Remote Switching of a Magneto-Active Liquid

Advanced Sustainable Systems ◽

10.1002/adsu.201700140 ◽

2017 ◽

Vol 2 (1) ◽

pp. 1700140 ◽

Cited By ~ 8

Author(s):

Benjamin P. V. Heiz ◽

Zhiwen Pan ◽

Lingqi Su ◽

Si Thien Le ◽

Lothar Wondraczek

Keyword(s):

Solar Thermal ◽

Smart Window ◽

Large Area ◽

Active Liquid

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Shape-Dependent Aggregation of Silver Particles by Molecular Dynamics Simulation

Crystals ◽

10.3390/cryst8110405 ◽

2018 ◽

Vol 8 (11) ◽

pp. 405 ◽

Cited By ~ 2

Author(s):

Xue Wang ◽

Chaofeng Hou ◽

Chengxiang Li ◽

Yongsheng Han

Keyword(s):

Building Blocks ◽

High Viscosity ◽

High Energy ◽

Dynamics Simulation ◽

Structure Evolution ◽

Shape Effect ◽

Silver Particles ◽

Large Area ◽

Research Problems ◽

High Possibility

In crystallization, nanoparticle aggregation often leads to the formation of orderly structures, even single crystals. Why can nanoparticles form orderly structures and what is the mechanism dominating their orderly aggregation? These questions raise interesting research problems, but the occurrences that could answer them often fail to be directly observed, since the interaction among particles is invisible. Here, we report an attempt to discover the interaction and aggregation of building blocks through a computer simulation, focusing on the shape effect of building blocks on the aggregation. Four types of silver building blocks were selected, each consisting of (100) and (111) facets, but the ratio of these two facets was different. It was found that the area of facets played an important role in selecting the aggregation mode. The facets with a large area and high energy had a high possibility of aggregation. In addition, the effects of solvent viscosity and temperature were also investigated. High viscosity and low temperature enhanced the orderliness of aggregation. This paper reports a detailed view of the aggregation process of silver nanoparticles, which is expected to be helpful in understanding the structure evolution of materials in nonclassical crystallization.

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Diameter dependent transparency changes of nanorod-based large-area flexible smart window devices

Journal of Materials Chemistry A ◽

10.1039/c8ta08716d ◽

2018 ◽

Vol 6 (47) ◽

pp. 24157-24165

Author(s):

Fuqiang Ren ◽

Shengyun Huang ◽

Fan Yang ◽

Aycan Yurtsever ◽

Dongling Ma

Keyword(s):

Structural Damage ◽

Optical Modulation ◽

Smart Window ◽

Large Area

Flexible SPDs achieve optical modulation as high as 73.7% and bending capability up to ∼180 degrees without any structural damage.

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Large-area display textiles integrated with functional systems

10.21203/rs.3.rs-56463/v1 ◽

2020 ◽

Author(s):

Huisheng Peng ◽

Xiang Shi ◽

Yong Zuo ◽

Peng Zhai ◽

Jiahao Shen ◽

...

Keyword(s):

Building Blocks ◽

Speech Disorders ◽

Communication Tool ◽

Electronic Textiles ◽

Large Area ◽

Practical Applications ◽

Contact Points ◽

Luminescent Coating ◽

And Function ◽

The Internet Of Things

Abstract Displays are basic building blocks of modern electronics1,2. Integrating displays into textiles offers exciting opportunities for smart electronic textiles – the ultimate form of wearables poised to change the way we interact with electronic devices3-6. Display textiles serve to bridge human-machine interactions7-9, offering for instance, a real-time communication tool for individuals with voice or speech disorders. Electronic textiles capable of communicating10, sensing11,12 and supplying electricity13,14 have been reported previously. However, textiles with functional, large-area displays have not been achieved so far because obtaining small illuminating units that are both durable and easy to assemble over a wide area is challenging. Here, we report a 6 m (L) * 25 cm (W) display textile containing 500000 electroluminescent (EL) units narrowly spaced to ~800 μm. Weaving conductive weft and luminescent warp fibres forms micron-scale EL units at the weft-warp contact points. Brightness between EL units deviates by < 6.3% and remains stable even when the textile is bent, stretched or pressed. We attribute this uniform and stable lighting to the smooth luminescent coating around the warp fibres and homogenous electric field distribution at the contact points. Our display textile is flexible and breathable and withstands repeatable machine-washing, making them suitable for practical applications. We show an integrated textile system consisting of display, keyboard and power supply can serve as a communication tool, which could potentially drive the Internet of Things in various areas including healthcare. Our approach unifies the fabrication and function of electronic devices with textiles, and we expect weaving fibre materials to shape the next-generation electronics.

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