Liquid Crystals: Versatile Self-Organized Smart Soft Materials

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(5), P. 4887 - 4926

Published: Dec. 23, 2021

Smart soft materials are envisioned to be the building blocks of next generation advanced devices and digitally augmented technologies. In this context, liquid crystals (LCs) owing their responsive adaptive attributes could serve as promising smart materials. LCs played a critical role in revolutionizing information display industry 20th century. However, turn 21st century, numerous beyond-display applications have been demonstrated, which elegantly exploit controllable stimuli-responsive characteristics. For these applications, new LC rationally designed developed. Review, we present recent developments light driven chiral LCs, i.e., cholesteric blue phases, based windows that control entrance heat from outdoor interior buildings built environments depending on weather conditions, elastomers for bioinspired, biological, actuator biosensors detection proteins, nucleic acids, viruses, porous membranes separation ions, molecules, microbes, living under macro- nanoscopic confinement. The Review concludes with summary perspectives challenges opportunities This is anticipated stimulate eclectic ideas toward implementation nature's delicate phase matter future generations beyond.

Language: Английский

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Nature‐Inspired Emerging Chiral Liquid Crystal Nanostructures: From Molecular Self‐Assembly to DNA Mesophase and Nanocolloids

Advanced Materials, Journal Year: 2018, Volume and Issue: 32(41)

Published: Aug. 30, 2018

Liquid crystals (LCs) are omnipresent in living matter, whose chirality is an elegant and distinct feature certain plant tissues, the cuticles of crabs, beetles, arthropods, beyond. Taking inspiration from nature, researchers have recently devoted extensive efforts toward developing chiral liquid crystalline materials with self-organized nanostructures exploring their potential applications diverse fields ranging dynamic photonics to energy safety issues. In this review, account on state art emerging nanostructured technological provided. First, overview significance architectures various systems given. Then, recent significant progress different including thermotropic LCs (cholesteric LCs, cubic blue phases, achiral bent-core etc.) lyotropic (DNA nanocellulose graphene oxide LCs) showcased. The review concludes a perspective future scope, opportunities, challenges these truly advanced functional soft promising applications.

Language: Английский

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Beyond the Visible: Bioinspired Infrared Adaptive Materials

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(14)

Published: Feb. 24, 2021

Abstract Infrared (IR) adaptation phenomena are ubiquitous in nature and biological systems. Taking inspiration from natural creatures, researchers have devoted extensive efforts for developing advanced IR adaptive materials exploring their applications areas of smart camouflage, thermal energy management, biomedical science, many other IR‐related technological fields. Herein, an up‐to‐date review is provided on the recent advancements bioinspired promising applications. First overview artificial technologies presented. Recent endeavors then introduced toward camouflage radiative cooling. According to Stefan‐Boltzmann law, can be realized by either emissivity engineering or cloaks. cooling maximize radiation object through atmospheric transparency window, thus holds great potential use energy‐efficient green buildings personal management advances emerging near‐IR (NIR) also discussed, including NIR‐triggered technologies, NIR light‐fueled soft robotics, light‐driven supramolecular nanosystems. This concludes with a perspective challenges opportunities future development materials.

Language: Английский

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Flexible Multifunctional Sensors for Wearable and Robotic Applications

Advanced Materials Technologies, Journal Year: 2019, Volume and Issue: 4(3)

Published: Jan. 4, 2019

Abstract This review provides an overview of the current state‐of‐the‐art emerging field flexible multifunctional sensors for wearable and robotic applications. In these application sectors, there is a demand high sensitivity, accuracy, reproducibility, mechanical flexibility, low cost. The ability to empower robots future electronic skin (e‐skin) with resolution, rapid response sensing capabilities interest broad range applications including healthcare devices, biomedical prosthesis, human–machine interacting such as service elderly provide diagnostic monitoring capabilities. A sensory mechanisms examined piezoelectric, pyroelectric, piezoresistive, particular emphasis on hybrid that capability. As alternative physical described above, optical have potential be used robot or e‐skin; this includes color changes using photonic crystals, liquid mechanochromic effects. Potential areas research are discussed challenge exciting materials enhance their integration into wearables

Language: Английский

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Liquid‐Crystal‐Mediated Geometric Phase: From Transmissive to Broadband Reflective Planar Optics

Advanced Materials, Journal Year: 2019, Volume and Issue: 32(27)

Published: Sept. 30, 2019

Abstract Planar optical elements that can manipulate the multidimensional physical parameters of light efficiently and compactly are highly sought after in modern optics nanophotonics. In recent years, geometric phase, induced by photonic spin–orbit interaction, has attracted extensive attention for planar due to its powerful beam shaping capability. The phase usually be generated via inhomogeneous anisotropic materials, among which liquid crystals (LCs) have been a focus. Their pronounced properties controllable stimuli‐responsive self‐assembly behavior introduce new possibilities LCs beyond traditional panel displays. Recent advances LC‐mediated briefly reviewed. First, several recently developed photopatterning techniques presented, enabling accurate fabrication complicated LC microstructures. Subsequently, nematic LC‐based transmissive chiral broadband reflective reviewed systematically. Versatile functionalities revealed, from conventional steering focusing, advanced structuring. Combining with structured materials offers satisfactory platform desired drastically extends exceptional applications ordered soft matter. Some prospects on this rapidly advancing field also provided.

Language: Английский

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Optically Rewritable Transparent Liquid Crystal Displays Enabled by Light‐Driven Chiral Fluorescent Molecular Switches

Advanced Materials, Journal Year: 2019, Volume and Issue: 31(10)

Published: Jan. 11, 2019

Functional soft materials exhibiting distinct functionalities in response to a specific stimulus are highly desirable towards the fabrication of advanced devices with superior dynamic performances. Herein, two novel light-driven chiral fluorescent molecular switches have been designed and synthesized that able exhibit unprecedented reversible Z/E photoisomerization behavior along tunable fluorescence intensity both isotropic anisotropic media. Cholesteric liquid crystals fabricated using these new as dopants reflection color tuning spanning visible infrared region spectrum. Transparent display low chirality high cholesteric films operate either exclusively mode or mode, respectively. The dual device employing short pitch film is function on demand under all ambient light conditions including daylight darkness fast resolution. Moreover, proof-of-concept for "remote-writing board" containing one ease operation disclosed herein. Such optically rewritable transparent enabled by pave way developing technology different lighting conditions.

Language: Английский

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Advances in Functional Solution Processed Planar 1D Photonic Crystals

Advanced Optical Materials, Journal Year: 2018, Volume and Issue: 6(24)

Published: Aug. 23, 2018

Abstract An overview on the properties and applications of polymer inorganic planar 1D photonic crystals fabricated from solution is provided here. In last decades, became technologically relevant for light management, photovoltaics, sensing, lasing. Such structures are traditionally produced by lithographic vacuum techniques, but need to reduce costs scale‐up fabrication have lead research toward new materials, simplified structures, low‐cost mass scale growth processes. this regard, mesoporous distributed Bragg reflectors attracted considerable technological interest. This review focuses such concentrating state‐of‐the‐art applications.

Language: Английский

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Dynamic Control of Light Direction Enabled by Stimuli‐Responsive Liquid Crystal Gratings

Advanced Materials, Journal Year: 2018, Volume and Issue: 31(7)

Published: Dec. 20, 2018

Abstract The ability to control light direction with tailored precision via facile means is long‐desired in science and industry. With the advances optics, a periodic structure called diffraction grating gains prominence renders more flexible over propagation when compared prisms. Today, gratings are common components wavelength division multiplexing devices, monochromators, lasers, spectrometers, media storage, beam steering, many other applications. Next‐generation optical however, demand nonmechanical, full remote control, besides generating higher than 1D patterns as few elements possible. Liquid crystals (LCs) great candidates for since they can form various under different stimuli, including structures capable of behaving gratings. characteristics such depend on several physical properties LCs film thickness, periodicity, molecular orientation, all resulting from internal constraints sample, these easily controllable. In this review, authors summarize research development stimuli‐controllable steering using active materials. Dynamic fabricated by applying external field forces or surface treatments made chiral nonchiral without polymer networks described. LC switching stimuli light, electric magnetic fields, heat, chemical composition discussed. focus materials, designs, applications, future prospects materials layers.

Language: Английский

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Supramolecular Chirality Transfer toward Chiral Aggregation: Asymmetric Hierarchical Self‐Assembly

Advanced Science, Journal Year: 2021, Volume and Issue: 8(8)

Published: March 1, 2021

Abstract Self‐assembly, as a typical bottom‐up strategy for the fabrication of functional materials, has been applied to fabricate chiral materials with subtle nanostructures. The nanostructures exhibit great potential in asymmetric catalysis, sensing, electronics, photonics, and even realization several biological functions. According existing studies, supramolecular chirality transfer process combined hierarchical self‐assembly plays vital role multiscale structures. This progress report focuses on or achiral molecules that aggregate spatial structures such twisted bands, helices, superhelices different environments. Herein, recent studies induced based variety interactions are summarized. In addition, influence environments states systems including solutions, condensed states, gel systems, interfaces self‐assembly, expression explored. Moreover, both driving forces facilitate bias play an important expression, transfer, amplification sense correspondingly discussed.

Language: Английский

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Fluorescent Photochromic α‐Cyanodiarylethene Molecular Switches: An Emerging and Promising Class of Functional Diarylethene

Advanced Functional Materials, Journal Year: 2020, Volume and Issue: 31(7)

Published: Nov. 3, 2020

Abstract Fluorescent photochromic molecules that exhibit distinct light‐triggered changes in their emission colors are highly desirable for the fabrication of smart soft materials and advanced photonic devices. α‐Cyanodiarylethenes, is, α‐cyano‐functionalized diarylethenes, as alternative “non‐azo” Z/E molecular switches, popular choices due to unique characteristics such aggregation‐induced or aggregation‐induced‐enhanced behavior self‐assembled states, visible fluorescence during photoisomerization. In recent years, development fluorescent α‐cyanodiarylethene‐based compounds including α‐cyanostilbenes, dicyanodistyrylbenzenes, diaryldicyanoethenes, has mainly focused on design, photochemical photophysical solution, matter technologies. this review, significant achievements light‐responsive systems based photoisomerization α‐cyanodiarylethene switches span range from liquid crystals gels finally nanostructures, highlighted. The constructed find use a plethora areas, display, sensing, encrypting, actuating, biomedical imaging applications, among others. review concludes with brief perspective some major challenges opportunities future materials.

Language: Английский

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