A pair of dual-stimulus-induced movable enantiomeric chiral tetrastable [3]rotaxanes are readily constructed via a threading-stoppering-methylating strategy, displaying tunable photochromic properties ascribed to acid-base-driven reversible mechanical motions that govern the controlled confinement and release of the two macrocycles on the dithienylethene (DTE) moiety. Interestingly, when two chiral rings approach the photoactive site, the inherently achiral DTE segment can be induced to acquire chirality through the conformational confinement of macrocycles. Crucially, the induced chirality can be effectively modulated by acid-base and distinct light through the dynamic interplay between reversible photoisomerization and confinement/release processes.

Developing all-visible light-activated diarylethene (DAE) molecular photoswitches hold great promise for high-resolution bioimaging and smart photoresponsive materials. Herein, we demonstrate that a bicomponent system comprising low-toxicity ZnSe/ZnS quantum dots (QDs) and carboxylated DAEs achieves all-visible light-activated photoswitching through a single-step triplet energy transfer (TET) in both organic and aqueous media. The photoswitching process exhibits reversible photoisomerization and fatigue resistance over multiple cycles under alternating 405 and 590nm irradiation. The photocyclization quantum yield ( = 55%) of DAEs in our design represents a record-high efficiency of DAEs under visible light activation compared with previously reported QD-sensitized and organic-sensitized systems. The high yield stems from the enhanced quality and a large molar extinction coefficient of ZnSe/ZnS QDs and efficient TET from ZnSe/ZnS QDs to dynamically enchored DAEs. Importantly, a biocompatible photoswitching system was constructed through the self-assembly of amphiphilic 1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-polyethylene glycol with the mixture of DAEs and ZnSe/ZnS QDs, enabling efficient and reversible photoisomerization of DAEs under all-visible light irradiation in aqueous media. Our strategy not only paves the way for advancing the development of all-visible light-activated optoelectronic devices but also creates new opportunities in further biological applications.

Controlling enzyme activity with external triggers is a central goal in chemical biology. Light is an especially attractive stimulus because it is noninvasive, offers high spatiotemporal precision, and can reversibly modulate molecular function. In this study, we use nucleoside-based diarylethenes (DAEs) to achieve light-dependent control of the RNA-cleaving deoxyribozyme (DNAzyme) 8-17. Three high-performing DAE-modified 2'-deoxyuridines were incorporated at structurally informed positions within the DNAzyme. A single optimal combination, dU-PhtBu at position 2.1, afforded efficient, reversible photocontrol: in the photostationary state after ultraviolet irradiation (PSSUV), the catalytic rate is reduced ∼11-fold relative to the all-open form (OF), while comparison of isolated OF and closed form (CF) reveals an ∼200-fold difference in activity. The switch is thermally robust and can be cycled repeatedly with minimal loss of function. In contrast, seemingly minor changes in DAE substitution, such as addition of a single methyl group, abolish useful regulation, underscoring the critical interplay between photoswitch structure and biomolecular context.

Photolabile protecting groups (PPGs) enable spatiotemporal control of chemical and biological processes, yet multistimuli-regulated systems remain rare. Here we report a triple-stimuli platform integrating light, base, and acid to control PPG release. Photoirradiation of diarylethenes (DAEs) under basic conditions generates stable 9,10-dihydrophenanthrene (9,10-DHP) intermediates that activate hemiaminal ethers and undergo acid-promoted aromatization to release the alcohol group. Distinct fluorescence changes allow real-time monitoring in both organic and aqueous media.

Organizing upconversion functionality into an integrated material system holds great promise for high-security encryption and data diversification. However, the practical application of facile upconversion imaging has long been hindered by its limited active area. Herein, we address this challenge by designing a holographic polymer waveguide composed of liquid crystals (LCs) and dithienylethene (DTE) as the high-refractive-index phase, with a polymer matrix embedded with upconversion nanoparticles serving as the low-refractive-index phase. This design enables the transformation of upconversion emission from a localized point to a macroscopic area, expanding the imaging region by up to 225 times. Mechanistic studies reveal that the synergy between LCs and DTE is crucial: the high-refractive-index LCs facilitate waveguiding, while DTE promotes the formation of well-defined holographic waveguide structures. Beyond this conceptual advance, the holographic polymer waveguide has successfully enabled triple-mode image encryption-integrating solidified holograms with rewritable upconversion and photochromic images-thereby opening new avenues for high-security anticounterfeiting technologies.

We investigate the electronic structure of two dithienylethene (DTE) molecular photoswitches, BTF6 and PTF6, in the gas phase by combining valence photoelectron spectroscopy (PES), x-ray photoelectron spectroscopy, and the near-edge x-ray absorption fine structure. DTEs have attracted significant attention due to their high photoisomerization quantum yield, fatigue resistance, and thermal irreversibility, which underpin applications ranging from molecular machines to photoswitchable biomolecules. Supported by first-principles simulations, our analysis elucidates how the different extent of π-conjugation, arising from the distinct thiophene/benzothiophene subunits, manifests across the various spectroscopic observables. By comparing the calculated signatures of the open- and closed-ring isomers, we further assess the sensitivity of each probe to the structural changes associated with photoinduced cyclization. Overall, these results deliver a detailed picture of the intrinsic electronic properties of DTEs in the gas phase and provide a robust basis for future time-resolved studies of their ultrafast photoisomerization dynamics.

ABSTRACT Photochromic materials offer dynamic modulation of optical properties, but their integration into lithographically defined photonic structures remains limited. Here, we report diarylethene (DAE)‐doped SU‐8 ( DAE‐SU‐8 ) thin films and waveguides as a CMOS‐compatible photochromic platform for light‐controlled integrated photonics. The DAE‐SU‐8 films exhibit reversible switching between colorless open‐ring isomer and colored closed‐ring isomer, thereby enabling rewritable optical patterning. High‐contrast images, QR codes, and diffraction gratings with micrometer‐scale resolution are demonstrated. Furthermore, lithographically patterned SU‐8 waveguides act as photo‐switchable variable optical attenuators, achieving tunable insertion loss exceeding 90 dB, and as Y‐branch structures that enable port‐selective attenuation. These results establish DAE‐SU‐8 as a versatile photochromic material system bridging rewritable optics with reconfigurable integrated photonic circuits, opening new opportunities for optical data storage, security encoding, and programmable integrated photonics.

Understanding and controlling the excited-state pathway dynamics of molecular photoswitches is critical for achieving rapid, efficient, and fatigue-resistant photoisomerization. Conventional diarylethenes (DAEs) undergo close-ring isomerization via nonadiabatic transitions involving conical intersections or intersystem crossing, which often introduce energetic losses and limited quantum yields. Herein, we report a new class of linearly coupled dithienylethene (DTE) derivatives that exhibit unprecedented photoisomerization behavior governed by an adiabatic excited-state mechanism. Spectroscopic analyses confirmed rapid switching and high conversion efficiency under ultraviolet irradiation, while quantum chemistry calculations revealed a smooth, barrierless evolution along the S1 surface without the involvement of surface crossings. This preoccupied adiabatic isomerization pathway enables efficient energy utilization and rapid photoreactivity of the system. This discovery introduces a rare example of adiabatic photoisomerization in DTEs and establishes a conceptual framework for designing high-performance photoswitches with tailored excited-state dynamics.

Photoisomerization‐induced solubility change of a photochromic diarylethene (DAE) derivative is investigated by a combination of theoretical calculations and experimental measurements. A significant solubility change is experimentally observed between two DAE photoisomers (open and closed forms) in n ‐octane solution. To elucidate the reason for the observed solubility change, we adopt a thermodynamic model and consider both ideal and nonideal contributions. The analysis revealed that both the crystalline stability of the isomers and their solute–solvent interactions play critical roles in determining the solubility difference. We believe that the current elucidation of thermodynamic properties will be useful to develop new functions of the DAE derivatives and future applications.

We synthesized and studied phosphetene‐bridged dithienylethenes (DTEs), featuring 4‐membered P‐rings, exploring their P‐chemistry and ring strain reactivity that allowed us to isolate 5‐membered oxophospholenes. Experimental and density functional theory (DFT) studies revealed how these modifications influence photochromic properties, with an impact of the P‐environment on the photokinetic metrics, demonstrating the value of 4‐membered strained P‐rings for tunable photoresponse. These systems exhibit good fatigue resistance including in the solid‐state. This work highlights phosphorus‐based molecular engineering as a powerful strategy for designing advanced photochromic materials.

Two-dimensional organic molecular crystals (2DOMCs) have emerged as promising candidates for next-generation ultrathin electronics. However, precisely and reversibly modulating their charge-transport characteristics remains a significant challenge. Herein, we report a molecular engineering strategy to create light-programmable field-effect transistors (FETs) based on a monolayer thick 2DOMCs, which is achieved by dispersing photochromic diarylethene (DAE) guests into a crystal host matrix of 2,6-bis(4-hexylphenyl) anthracene (C6-DPA). By systematically functionalizing the DAE periphery with substituents of varying electron-donating and -withdrawing strengths, we precisely tune the HOMO energy levels of the guest molecules. We identify DAE-OCH3 as the optimal dopant, which enables a 54% modulation of the FET current within just 5 s of UV light "writing" process. Notably, the optimized C6-DPA/DAE-OCH3 (15%) guest-host system exhibits approximately 85 distinct and stable current levels, corresponding to a storage capacity exceeding 6 bits, with excellent retention over 16 days. This performance represents a significant advancement in ultrathin multilevel memories based on high-mobility organic semiconductors. Our approach establishes a general platform for developing stimuli-responsive 2D organic materials with programmable (opto)electronic properties, opening new avenues for high-density data storage and future generation intelligent (opto)electronics.

The diarylethenes (DAEs), renowned for their reversible photoisomerization, exhibit tunable bandgaps, conductivity, intramolecular or intermolecular radical and energy transfer processes. Leveraging these properties, we designed a DAE based polymer (DEP), and incorporated it as an additive in the photoactive layer of organic photodiodes (OPDs). Radical intermediates of DEP can enhance the photo response of OPDs. With 6wt.% of DEP in PM6:PC61BM, the suppressed dark current density (Jd) of 1.20 × 10-9 A cm-2, increased photocurrent density (Jp) of 9.66 × 10-4 A cm-2 and superior detectivity (D*) of 2.02 × 1013 Jones are measured at -2V under 630nm irradiation, which shows superior performances to its counterpart with Jd of 4.31×10-7Acm-2, Jp of 7.02×10-4Acm-2, and D* of 8.38 × 1011 Jones without DEP. Mechanistic studies reveal that DEP suppresses dark current by modulating the bandgap and molecular interaction. Meanwhile, the distinct photo response of doped OPDs is attributed to enhanced exciton diffusion and to positive photoconductivity from photoinduced radical intermediates.

ABSTRACT Optically switchable functions are highly interesting for AI applications in smart displays, memory encryption, and neuromorphic computing. The use of molecular photoswitches to precisely modulate functionalities at the nanoscale, such as photoluminescence (PL), is essential for developing photoswitchable nanomaterials. However, it is challenging to achieve the universal regulation of full‐color PL, particularly for the efficient optical modulation while maintaining both high PL quantum yield (PLQY) and effective photoswitchable states. Herein, we report a simple and efficient photoswitchable system achieved through the hybridization of quantum dots (QDs) and diarylethene (DAE) photoswitches. The PL intensity of the three primary colors (RGB) can be reversibly switched on and off using the same DAE upon exposure to specific light. Our design exhibits a maximum PLQY exceeding 90% in the on state while maintaining a PL on/off ratio approaching 100, which represents one of the current highest values. The excellent performance relies on the synergistic energy transfer mechanism of the Förster resonance energy transfer and triplet energy transfer. Our photoswitchable materials enable the straightforward preparation of RGB QDs@DAE films for applications in reversible patterned display and information encryption. The patterns and information can be erased and rewritten multiple times, offering flexible and reusable smart materials toward data storage, advanced display, and anti‐counterfeiting technologies.

Abstract Diarylethenes (DAEs), a class of photochromic compounds, exhibit excellent fatigue resistance and thermal stability, and their photochemical properties can be tuned through modification of the ethene or aryl moieties, making them attractive photoresponsive materials. We focused on diarylmaleimide (DAM)-S,S,S′,S′-tetraoxide derivatives as switchable, highly polar fluorescent DAE derivatives. To increase polarity compared with the previously reported DAM 1 and its S,S,S′,S′-tetraoxide derivative 2, we designed 5 bearing a triethylene glycol substituent and its S,S,S′,S′-tetraoxide derivative 6, and synthesized N-H maleimide analogs 3 and 4 as references. 3 and 5 showed reversible photochromism under 436- and 550-nm irradiation with weak fluorescence quenching, whereas 4 and 6 exhibited partial two-way photoisomerization in ethanol, switchable to one-way depending on solvent polarity. Photochemical properties in aqueous systems were examined in water/ethanol mixtures. In 75% water/ethanol, the closed-ring form formed aggregates emitting fluorescence distinct from the solution state, enabling color switching. Among 2, 4, and 6, 6 formed the largest and fastest-growing aggregates and displayed blue-shifted aggregation-induced emission enhancement (AIEE). To the best our knowledge, this is the first report that DAM-S,S,S′, S′-tetraoxide derivatives exhibiting AIEE with distinct emission colors between solution and aggregate states. These findings provide new insight into designing multi-color, multi-state photoresponsive materials. AIEE has attracted significant attention for applications in bioimaging, chemical sensing, and organic electronics, and the present results further suggest potential in these areas.

Achieving high efficiency in visible-light-driven dithienylethene (DTE) derivatives remains a significant challenge due to inherent limitations such as low ring-closing reactivity and poor conversion efficiency. In this work, a novel DTE derivative (3) was rationally designed and successfully prepared in which the N,N-dimethylaniline units are covalently linked to the DTE core via an alkene group as a π-bridge, thereby extending the π-conjugated system. As expected, the resulting DTE structure 3 displays efficient photochromism in different solvents when alternately irradiated with purple (λ = 420 nm) and red (λ = 600 nm) light. Remarkably, ring-open isomer 3(o) reaches the photostationary state (PSS) within 3 s under 420 nm irradiation and achieves near-quantitative conversion efficiency. Importantly, DTE derivative 3 maintains excellent photoswitching properties even in DMSO and nano-aqueous solution, with only a minor attenuation. Furthermore, the DTE 3-loaded poly(methyl methacrylate) (PMMA) film also exhibits enhanced photoswitching performance upon irradiation with purple light. The experimental findings are in agreement with time-dependent density functional theory (TD-DFT) calculations. Consequently, taking the advantages of excellent photochromism and fluorescence emission of this novel DTE derivative, it may be a promising candidate applied as functional optical materials.

Organic thermoelectric materials capable of converting heat into electricity become important for sustainable energy conversion. Single-molecule thermoelectric devices present a promising opportunity for high-efficiency thermopower conversion by precisely controlling molecular energy levels, which induces energy-dependent transport asymmetry and consequently enhances the Seebeck coefficient. However, scalable thermopower output remains constrained by the challenges of assembling heteromolecular thermoelectric units with opposite polarities, whereas dynamic in situ control over the polarity of the Seebeck coefficient offers a feasible strategy for overcoming this limitation. Here, we report a photoresponsive single-molecule bithermoelectric device based on dithienylethene (DTE) derivatives using the scanning tunneling microscope break-junction (STM-BJ) technique with a thermoelectric module. The Seebeck coefficient could be reversibly switched between positive (P-type) and negative (N-type) values upon respective UV and visible light irradiation, as confirmed by thermoelectric measurements and density functional theory (DFT) calculations. By assembling an array of DTE monolayer with an optical mask to partially trigger the photoisomerization, we experimentally realized alternating P-type and N-type DTE molecular junctions connected through interleaved top and bottom electrodes, yielding a series-integrated molecular thermoelectric device with an amplified thermopower output over 9000 μV under a temperature gradient of 30 K. This study presents a viable strategy for realizing programmable and scalable molecular thermoelectrics by utilizing photoswitchable bithermoelectric molecular devices.

Sulfhydryl group (SH) plays important roles in reactions with various functional groups, especially in biologically active systems. Photoswitchable diarylethene (DAE) derivatives have demonstrated applications in many research fields. Among the many classes of diarylethene derivatives, thiol derivatives have not been extensively explored. In this study, we systematically synthesized and characterized a series of bis-thiol functionalized dithienylethene derivatives. The thiol groups in this series are attached directly to the thiophene, or through a phenyl or methylene linker. Each series incorporated both dithienyl cyclopentene and hexafluorocyclopentene bridges and total six thiol substituted diarylethenes were synthesized. Among the six sulfhydryl DAE derivatives, four compounds were synthesized for the first time. Due to the reactivity of the thiol, they were prepared and stored as the corresponding thiol acetates. The photoswitching properties of the acetylated thiol derivatives were characterized. Three new thiol derivatives exhibited intriguing ‘turn-on’ fluorescence behavior, where the open isomers are non-fluorescent, while the closed isomers display fluorescence. These compounds represent a new class of fluorescent diarylethenes that do not require additional fluorophores. The thiol functional group offers potential for biological conjugation reactions and application as fluorescent probes.

Research on organic semiconductors has increasingly focused on developing multifunctional devices, leveraging their inherent advantages such as lightweight properties, low-cost fabrication, and tunable optoelectronic characteristics. Within this context, the exploration of molecular switches, particularly diarylethenes (DAEs), for precise current modulation in transistors has garnered significant interest. While the optimal molecular switch design has been extensively studied, advancements in transistor architecture have remained limited. This work introduces a novel approach utilizing organic Schottky barrier transistors (OSBTs), a type of organic vertical transistor featuring a distinct operation mechanism in terms of conductive channel formation and charge injection, enabling superior hole-trapping efficiency compared with conventional organic field-effect transistors (OFETs). By incorporating a dielectric/metal/dielectric transparent electrode to mitigate light-irradiation limitations, we successfully integrated DAEs into OSBTs, achieving a record-high photoprogrammable switching ratio exceeding 6.4 × 104 at a 30 wt% DAE concentration. The physics underlying the superior performance of OSBTs compared to that of OFETs is explained, with a focus on the distinct gate-field effect. Furthermore, stable switching performance was maintained over 100 repeated cycles, demonstrating exceptional fatigue resistance. This innovative architecture paves the way for the development of high-performance photoprogrammable transistors.

We report the first complete experimental resolution of the configurational landscape of a phenanthrene-bridged diarylethene (DAE) with unsymmetrical substitution.

Diarylethene (DAE)-based photochromic molecules, e.g., dithienylethenes, have emerged as versatile candidates for molecular switching over a very broad application range. Their popularity can be rationalized by the robust reversible photo-induced...