Bioinspired MXene-Based Soft Actuators Exhibiting Angle-Independent Structural Color.

In nature, many living organisms exhibiting unique structural coloration and soft-bodied actuation have inspired scientists to develop advanced structural colored soft actuators toward biomimetic soft robots. However, it is challenging to simultaneously biomimic the angle-independent structural color and shape-morphing capabilities found in the plum-throated cotinga flying bird. Herein, we report biomimetic MXene-based soft actuators with angle-independent structural color that are fabricated through controlled self-assembly of colloidal SiO nanoparticles onto highly aligned MXene films followed by vacuum-assisted infiltration of polyvinylidene fluoride into the interstices.

Hypoxia-Responsive Photosensitizer Targeting Dual Organelles for Photodynamic Therapy of Tumors.

Developing safe and precise image-guided photodynamic therapy is a challenge. In this study, the hypoxic properties of solid tumors are exploited to construct a hypoxia-responsive photosensitizer, TPA-Azo. Introducing the azo group into the photosensitizer TPA-BN with aggregation-induced emission quenches its fluorescence.

Stretchable and self-healable spoof plasmonic meta-waveguide for wearable wireless communication system.

Microwave transmission lines in wearable systems are easily damaged after frequent mechanical deformation, posing a severe threat to wireless communication. Here, we report a new strategy to achieve stretchable microwave transmission lines with superior reliability and durability by integrating a self-healable elastomer with serpentine-geometry plasmonic meta-waveguide to support the spoof surface plasmon polariton (SSPP). After mechanical damage, the self-healable elastomer can autonomously repair itself to maintain the electromagnetic performance and mechanical strength.

Amphiphilicity-Controlled Polychromatic Emissive Supramolecular Self-Assemblies for Highly Sensitive and Efficient Artificial Light-Harvesting Systems.

Dynamic sequential control of photoluminescence by supramolecular approaches has become a great issue in supramolecular chemistry. However, developing a systematic strategy to construct polychromatic photoluminescent supramolecular self-assemblies for improving the efficiency and sensitivity of artificial light-harvesting systems still remains a challenge. Here, a series of amphiphilicity-controlled supramolecular self-assemblies with polychromatic fluorescence based on lower-rim hexyl-modified sulfonatocalix[4]arene (SC4A6) and N-alkyl-modified p-phenylene divinylpyridiniums (PVPn, n = 2-7) as efficient light-harvesting platforms is reported.

Liquid and Photoliquefiable Azobenzene Derivatives for Solvent-free Molecular Solar Thermal Fuels.

A series of liquid and photoliquefiable azobenzene (Azo) derivatives (Azo-C-Br) have been synthesized for molecular solar thermal fuels. Each of the liquid and photoliquefiable azo derivatives shows a high degree of isomerization, a fast isomerization rate, a long half-life, an appropriate energy storage density, and a solvent-free "charging" and "discharging" process. The photoliquefied azo derivatives can isomerize upon UV light irradiation at low temperatures to give the "UV-charged" azo ones.

Asymmetric ultrathin silica nanonets as a super-performance emulsifier.

Hypothesis: Pickering emulsions have been used in many fields such as catalytic synthesis, pharmaceutics and oilfield chemicals. They usually have good stability, but in some extreme conditions such as at high temperatures or in special liquid-liquid systems, poor stability is often encountered.

Experiments: Herein, ultrathin silica nanosheets with controllable morphologies were synthesized via a simple interfacial anisotropic self-assembly approach integrated with pore-forming techniques.

A high mobility air-stable n-type organic small molecule semiconductor with high UV-visible-to-NIR photoresponse.

An organic semiconductor with high carrier mobility and efficient light absorption over a wide spectral range is of the most important yet challenging material for constructing a broadband responsive organic photodetector. However, the development of such organic semiconductors, especially for air-stable n-type organic small molecule semiconductors, is still at an early stage. Here we report the fabrication of high-performance n-type semiconducting crystalline nanosheets and the development of air-stable field-effect transistors, phototransistors, with high response over a broad spectrum.

Liquid crystal-templated chiral nanomaterials: from chiral plasmonics to circularly polarized luminescence.

Chiral nanomaterials with intrinsic chirality or spatial asymmetry at the nanoscale are currently in the limelight of both fundamental research and diverse important technological applications due to their unprecedented physicochemical characteristics such as intense light-matter interactions, enhanced circular dichroism, and strong circularly polarized luminescence. Herein, we provide a comprehensive overview of the state-of-the-art advances in liquid crystal-templated chiral nanomaterials. The chiroptical properties of chiral nanomaterials are touched, and their fundamental design principles and bottom-up synthesis strategies are discussed.

Light-activated photodeformable supramolecular dissipative self-assemblies.

Dissipative self-assembly, one of fundamentally important out-of-equilibrium self-assembly systems, can serve as a controllable platform to exhibit temporal processes for various non-stimulus responsive properties. However, construction of light-fueled dissipative self-assembly structures with transformable morphology to modulate non-photoresponsive properties remains a great challenge. Here, we report a light-activated photodeformable dissipative self-assembly system in aqueous solution as metastable fluorescent palette.

Dynamically actuated soft heliconical architecture via frequency of electric fields.

Dynamic electric field frequency actuated helical and spiral structures enable a plethora of attributes for advanced photonics and engineering in the contemporary era. Nevertheless, leveraging the frequency responsiveness of adaptive devices and systems within a broad dynamic range and maintaining restrained high-frequency induced heating remain challenging. Herein, we establish a frequency-actuated heliconical soft architecture that is quite distinct from that of common frequency-responsive soft materials.

Synchronous Imaging in Golgi Apparatus and Lysosome Enabled by Amphiphilic Calixarene-Based Artificial Light-Harvesting Systems.

Artificial supramolecular light-harvesting systems have expanded various properties on photoluminescence, enabling promising applications on cell imaging, especially for imaging in organelles. Supramolecular light-harvesting systems have been used for imaging in some organelles such as lysosome, Golgi apparatus, and mitochondrion, but developing a supramolecular light-harvesting platform for imaging two organelles synchronously still remains a great challenge. Here, we report a series of lower-rim dodecyl-modified sulfonato-calix[4]arene-mediated supramolecular light-harvesting platforms for efficient light-harvesting from three naphthalene diphenylvinylpyridiniums containing acceptors, Nile Red, and Nile Blue.

Visible Light-Driven Molecular Switches and Motors: Recent Developments and Applications.

Inspired by human vision, a diverse range of light-driven molecular switches and motors have been developed for fundamental understanding and application in material science and biology. Recently, the design and synthesis of visible light-driven molecular switches and motors have been actively pursued. This emerging trend is partly motivated to avoid the harmful effects of ultraviolet light, which was necessary to drive the classical molecular switches and motors at least in one direction, impeding their employment in biomedical and photopharmacology applications.

Liquid Crystals: Versatile Self-Organized Smart Soft Materials.

Smart soft materials are envisioned to be the building blocks of the next generation of advanced devices and digitally augmented technologies. In this context, liquid crystals (LCs) owing to their responsive and adaptive attributes could serve as promising smart soft materials. LCs played a critical role in revolutionizing the information display industry in the 20th century.

Stimulus-driven liquid metal and liquid crystal network actuators for programmable soft robotics.

Sophisticated soft matter engineering has been endorsed as an emerging paradigm for developing untethered soft robots with built-in electronic functions and biomimetic adaptation capacities. However, the integration of flexible electronic components into soft robotic actuators is challenging due to strain mismatch and material incompatibilities. Herein, we report a general strategy to integrate electrically conductive liquid metals (LMs) and shape-morphing liquid crystal networks (LCNs) towards multifunctional and programmable soft robotics.

A Liquid Crystal Elastomer-Based Unprecedented Two-Way Shape-Memory Aerogel.

With the advantage of reversible shape-morphing between two different permanent shapes under external stimuli, the two-way shape-memory aerogel is expected to become a preferred aerogel for developing practical applications in actuators, sensors, robotics, and more. Herein, the first two-way shape-memory liquid crystal elastomer (LCE)-based aerogel is prepared by an orthogonal heat and light curing strategy coupled with an intermediate mechanical stretching step. The differential scanning calorimetry, temperature-varied wide-angle X-ray scattering, and polarizing optical microscope results indicate that the aerogel possesses a liquid crystal phase and the insider mesogens are well-oriented along the stretching direction.

Irradiation-Wavelength Directing Circularly Polarized Luminescence in Self-Organized Helical Superstructures Enabled by Hydrogen-Bonded Chiral Fluorescent Molecular Switches.

Two light-driven chiral fluorescent molecular switches, (R,S,R)-switch 1 and (R,S,R)-switch 2, are prepared by means of hydrogen-bonded (H-bonded) assembly of a photoresponsive (S) chiral fluorescent molecule, respectively with a cyano substitution at different positions as an H-bond acceptor and an opposite (R) chiral molecule as an H-bond donor. The resulting two switches exhibit tunable and reversible Z/E photoisomerization irradiated with 450 nm blue and 365 nm UV light. When doped into an achiral liquid crystal, both switches are found to be able to form a CPL tunable luminescent helical superstructure.

Stimuli-Driven Insulator-Conductor Transition in a Flexible Polymer Composite Enabled by Biphasic Liquid Metal.

Metal-polymer composites (MPCs) with combined properties of metals and polymers have achieved much industrial success. However, metals in MPCs are thought to be ordinary and invariable electrically conductive fillers in supportive polymers to show limited use in modern technologies. This work that is disclosed here, for the first time, introduces stimuli-driven transition from biphasic to monophasic state of liquid metal into polymer science to form dynamic soft conductors from the binary metal-polymer composites.

Light-fueled transient supramolecular assemblies in water as fluorescence modulators.

Dissipative self-assembly, which requires a continuous supply of fuel to maintain the assembled states far from equilibrium, is the foundation of biological systems. Among a variety of fuels, light, the original fuel of natural dissipative self-assembly, is fundamentally important but remains a challenge to introduce into artificial dissipative self-assemblies. Here, we report an artificial dissipative self-assembly system that is constructed from light-induced amphiphiles.

Covalent Adaptable Liquid Crystal Networks Enabled by Reversible Ring-Opening Cascades of Cyclic Disulfides.

The development of covalent adaptable liquid crystal networks (LCNs) enabled by introducing dynamic covalent bonds has endowed liquid crystal actuators with self-healing properties and reversible shape programmability, broadening their applications in diverse soft robotic devices. However, the finite molecular design strategy limits the recyclability and the architectural diversity of these materials. Here, a strategy is first reported for fabricating photoresponsive polydisulfide-based covalent adaptable LCNs by ring-opening polymerization of cyclic dithiolane groups.

Healable and Rearrangeable Networks of Liquid Crystal Elastomers Enabled by Diselenide Bonds.

Based on liquid crystal elastomer (LCE) materials, hierarchically structured soft actuators can meet some requirements for "human-friendly" working mode and execute complex tasks with intelligent adaptation to environmental changes. However, few researchers have paid much attention to the preparation methods of multicomponent/hierarchical LCE actuators. In this communication, we demonstrate the successful integration of an exchangeable diselenide chain extender for the preparation of dynamic LCEs, which could be reprogrammed on heating or under visible light illumination.

Supramolecular Chirality Transfer toward Chiral Aggregation: Asymmetric Hierarchical Self-Assembly.

Self-assembly, as a typical bottom-up strategy for the fabrication of functional materials, has been applied to fabricate chiral materials with subtle chiral nanostructures. The chiral nanostructures exhibit great potential in asymmetric catalysis, chiral sensing, chiral electronics, photonics, and even the realization of several biological functions. According to existing studies, the supramolecular chirality transfer process combined with hierarchical self-assembly plays a vital role in the fabrication of multiscale chiral structures.

Unexpected organic hydrate luminogens in the solid state.

Developing organic photoluminescent materials with high emission efficiencies in the solid state under a water atmosphere is important for practical applications. Herein, we report the formation of both intra- and intermolecular hydrogen bonds in three tautomerizable Schiff-base molecules which comprise active hydrogen atoms that act as proton donors and acceptors, simultaneously hindering emission properties. The intercalation of water molecules into their crystal lattices leads to structural rearrangement and organic hydrate luminogen formation in the crystalline phase, triggering significantly enhanced fluorescence emission.

Liquid Crystals in Curved Confined Geometries: Microfluidics Bring New Capabilities for Photonic Applications and Beyond.

The quest for interesting properties and phenomena in liquid crystals toward their employment in nondisplay application is an intense and vibrant endeavor. Remarkable progress has recently been achieved with regard to liquid crystals in curved confined geometries, typically represented as enclosed spherical geometries and cylindrical geometries with an infinitely extended axial-symmetrical space. Liquid-crystal emulsion droplets and fibers are intriguing examples from these fields and have attracted considerable attention.

Bioinspired Synergistic Photochromic Luminescence and Programmable Liquid Crystal Actuators.

Bioinspired smart materials with synergistic allochroic luminescence and complex deformation are expected to play an important role in many areas of science and technology. However, it is still challenging to fabricate such soft actuators with high programmability that can be manipulated in situ with high spatial resolution. Herein, we have incorporated terminally functionalized aggregation-induced emission active tetraphenylethene derivative and photochromic spiropyran moieties into the networks of liquid crystal elastomers through covalent bonding to obtain the synergistic photochromic luminescence and programmable soft actuators.

Beyond the Visible: Bioinspired Infrared Adaptive Materials.

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 and exploring their applications in areas of smart camouflage, thermal energy management, biomedical science, and many other IR-related technological fields. Herein, an up-to-date review is provided on the recent advancements of bioinspired IR adaptive materials and their promising applications.