Photoluminescent and Chromic Nanomaterials for Anticounterfeiting Technologies: Recent Advances and Future Challenges

ACS Nano, Journal Year: 2020, Volume and Issue: 14(11), P. 14417 - 14492

Published: Oct. 20, 2020

Counterfeiting and inverse engineering of security confidential documents, such as banknotes, passports, national cards, certificates, valuable products, has significantly been increased, which is a major challenge for governments, companies, customers. From recent global reports published in 2017, the counterfeiting market was evaluated to be $107.26 billion 2016 forecasted reach $206.57 by 2021 at compound annual growth rate 14.0%. Development anticounterfeiting authentication technologies with multilevel securities powerful solution overcome this challenge. Stimuli-chromic (photochromic, hydrochromic, thermochromic) photoluminescent (fluorescent phosphorescent) compounds are most significant applicable materials development complex inks high-security level fast authentication. Highly efficient have developed high efficiency. Applicable applications generally based on photochromic compounds, hydrochromic thermochromic extensively used decades. A wide range materials, organic inorganic metal complexes, polymer nanoparticles, quantum dots, carbon upconverting supramolecular structures, could display all these phenomena depending their physical chemical characteristics. The polymeric recently received attention because stability printing documents. In addition, including hand-writing, stamping, inkjet printing, screen labels discussed introduction methods application different inks. This review would help scientists design develop encryption, authentication, security, detection, potential marking information encryption various substrates.

Language: Английский

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Colloidal Self-Assembly Approaches to Smart Nanostructured Materials

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(5), P. 4976 - 5067

Published: Nov. 8, 2021

Colloidal self-assembly refers to a solution-processed assembly of nanometer-/micrometer-sized, well-dispersed particles into secondary structures, whose collective properties are controlled by not only nanoparticle property but also the superstructure symmetry, orientation, phase, and dimension. This combination characteristics makes colloidal superstructures highly susceptible remote stimuli or local environmental changes, representing prominent platform for developing stimuli-responsive materials smart devices. Chemists achieving even more delicate control over their active responses various practical stimuli, setting stage ready fully exploiting potential this unique set materials. review addresses colloids nanostructured We first delineate driven forces different length scales. A concepts equations outlined controlling crystal growth, appreciating importance particle connectivity in creating responsive superstructures. then present working mechanisms strategies engineering assemblies. The underpinning separation systematically introduced, allowing tuning precise prediction response external stimuli. Various exciting applications these summarized with specific focus on structure-property correlation functional conclude summary existing challenges provide perspective further advances next generation.

Language: Английский

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Molecular photoswitches in aqueous environments

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(22), P. 12377 - 12449

Published: Jan. 1, 2021

Molecular photoswitches are inherently lipophilic and do not spontaneously dissolve in water. We describe the effect of water on photochemical properties strategies to solubilize organic apply them aqueous media.

Language: Английский

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Light-Driven Expansion of Spiropyran Hydrogels

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(18), P. 8447 - 8453

Published: April 24, 2020

The incorporation of molecular switches in organic structures is great interest the chemical design stimuli-responsive materials that mimic complex functions living systems. Merocyanine dyes convert to spiropyran moieties upon exposure visible light have been extensively studied as they can be incorporated hydrated covalent networks will expel water when this conversion occurs and induce a volumetric shrinkage. We report here on sulfonate-based water-soluble photoswitch that, contrast well-known systems, triggers expansion hydrogels photons. Contraction turn observed under dark conditions highly reversible manner. novel behavior network was predicted by coarse-grained simulations system's structure. Using pH control polymeric differ lower critical solution temperature, we were able develop with tunable expansion. function systems developed led negative phototaxis plants could expand potential use sensors, soft robots, actuators.

Language: Английский

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Photoresponsive molecular tools for emerging applications of light in medicine

Chemical Science, Journal Year: 2020, Volume and Issue: 11(43), P. 11672 - 11691

Published: Jan. 1, 2020

This perspective article explores the current state of light-controlled molecular tools for medical therapy and imaging offers an outlook on clinical application scenarios optimisation strategies.

Language: Английский

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Spiropyran-based advanced photoswitchable materials: A fascinating pathway to the future stimuli-responsive devices

Journal of Photochemistry and Photobiology C Photochemistry Reviews, Journal Year: 2022, Volume and Issue: 51, P. 100487 - 100487

Published: Jan. 21, 2022

Language: Английский

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Natural and Synthetic Flavylium-Based Dyes: The Chemistry Behind the Color

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(1), P. 1416 - 1481

Published: Nov. 29, 2021

Flavylium compounds are a well-known family of pigments because they prevalent in the plant kingdom, contributing to colors over wide range from shades yellow-red blue fruits, flowers, leaves, and other parts. include large variety natural compound classes, namely, anthocyanins, 3-deoxyanthocyanidins, auronidins, their respective aglycones as well anthocyanin-derived (e.g., pyranoanthocyanins, anthocyanin-flavan-3-ol dimers). During past few decades, there has been increasing interest among chemists synthesizing different flavylium that mimic structures but with substitution patterns present spectroscopic characteristics view applications industrial fields. This Review provides an overview chemistry flavylium-based compounds, particular, synthetic enzymatic approaches mechanisms reported literature for obtaining classes pigments, physical-chemical properties relation pH-dependent equilibria network, chemical degradation. The development systems is also described throughout this emergent explore some multistate species generated by these compounds.

Language: Английский

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Photoresponsive Supramolecular Polymers: From Light‐Controlled Small Molecules to Smart Materials

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(10)

Published: Oct. 14, 2022

Photoresponsive supramolecular polymers are well-organized assemblies based on highly oriented and reversible noncovalent interactions containing photosensitive molecules as (co-)monomers. They have attracted increasing interest in smart materials dynamic systems with precisely controllable functions, such light-driven soft actuators, photoresponsive fluorescent anticounterfeiting light-triggered electronic devices. The present review discusses light-activated used their main photo-induced changes, e.g., geometry, dipole moment, chirality. Based these distinct formed by exhibit disassembly reassembly. As a consequence, polymerization, "depolymerization," regulation of the lengths topologies observed. Moreover, light-controlled functions polymers, actuation, emission, chirality transfer along length scales, highlighted. Furthermore, perspective challenges future opportunities is presented. Besides challenge moving from harmful UV light to visible/near IR avoiding fatigue, enabling biomedical applications, include actuators helical motion, light-modulated information transmission, optically recyclable materials, multi-stimuli-responsive systems.

Language: Английский

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Storing energy with molecular photoisomers

Joule, Journal Year: 2021, Volume and Issue: 5(12), P. 3116 - 3136

Published: Nov. 22, 2021

Some molecular photoisomers can be isomerized to a metastable high-energy state by exposure light. These molecules then thermally or catalytically converted back their initial state, releasing heat in the process. Such reversible photochemical process has been considered for developing solar thermal (MOST) systems. In this review, we introduce concept, criteria, and state-of-the-art of MOST systems, with an emphasis on three most promising systems: norbornadiene/quadricyclane, E/Z-azobenzene, dihydroazulene/vinylheptafulvene. After discussing fundamental working principles, focus design strategies improving energy storage performance, remaining challenges, potential areas. Finally, summarize current incorporation into functional devices conclude perspective challenges future directions.

Language: Английский

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Lignin: a sustainable photothermal block for smart elastomers

Green Chemistry, Journal Year: 2021, Volume and Issue: 24(2), P. 823 - 836

Published: Dec. 4, 2021

Lignin was demonstrated to have excellent photothermal performance for smart applications in photo-controlled shape memory, self-healing, mechanical/electrical conversion, antibacterial materials, etc .

Language: Английский

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