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A visible-light driven solid-state NIR fluorescent bistable molecular switch was constructed by coupling bulky tetraphenylethylene, photochromic diarylethene and NIR emissive terrylene diimide. Multi-level optical storage was demonstrated based on its film.

Photochromic hexaarylbiimidazoles (HABIs) enable reversible transformation between HABI and triphenylimidazole radicals (TPIRs) upon UV light irradiation, which have been applied in photo-patterning, super-resolution imaging, photoinduced self-healing materials and photomechanical hydrogels. Here, we designed and prepared a novel kind of polyurethane (PU) photoresist based on photo-cleavable HABI cross-linkers (HABI-PU), linear PU backbone and additive tert-butylhydroquinone (TBHQ) radical quencher. Upon UV light irradiation, the C-N bond inside HABI unit is broken, causing the transformation of HABI into two TPIRs which are subsequently quenched by TBHQ. Therefore, the cross-linking points of HABI-PU in UV irradiation area were broken, forming flexible PU polymer chains with declined molecular weight, which can be dissolved in developer. HABI-PU films show excellent photosensitivity as a positive photoresist in photolithography. The reaction mechanism between HABI and TBHQ was studied by UV-vis absorption spectra, electron paramagnetic resonance (EPR), mass spectra and nuclear magnetic resonance spectra. The lithographic patterns were characterized through metallurgical microscope and scanning electron microscope with a resolution at about 5 µm.

Schematic diagram of dual treatment of bacterial infection.

Binding of a synthesized fluorescent probe to latent fingerprints results in the aggregation-induced emission of green light, which is better perceived by the human eye than other colors and provides up to three levels of minutiae characteristics of latent fingerprints.

Lacquer wood (LW) goes through one-step and two-step H3PO4 activation process to prepare activated carbons (ACs) at different temperature, and its performance was evaluated by testing CV, EIS, GCD and cycling respect to an electrode material in supercapacitors. The performance of lacquer wood activated carbon prepared by different activation methods and temperature (300, 400, 500, 600, 700, and 800 °C) was studied, and the influence on its electrochemical properties provides valuable guidance for the high-efficient energy utilization of lacquer wood. The results showed that the AC generated via one-step activation process at 400 °C demonstrate excellent specific surface area (SBET 1609.09 m2/g) than those from two-step activation method. Besides, the biomass-derived ACs presented overall better electrochemistry characteristic than those from charcoal-derived ACs. The largest specific capacitance (354 F/g) was obtained in the ACs-based electrodes which was generated from one-step activation process (activated at 600 °C). After 10000 cycles, its capacity retention reached 95.3%, which provides a meaningful guidance into the application of energy storage supercapacitors. This study proves that the LW derived ACs are promising electrodes of the high-performance supercapacitors, which is beneficial for value-added and industrial supercapacitors application of lacquer wood ACs.

Fallen leaves of landscape trees, as an emerging biomass waste, were valorized using conventional hydrothermal carbonization (HC) and microwave‐assisted hydrothermal carbonization (MHC) pretreatments, and were comparatively characterized for physicochemical properties and thermal degradation kinetics. The results show that MHC is superior to conventional HC operation, because at 200℃, the MHC process not only gives a higher hydrochar yield (45.09 vs. 39.47 wt%) with significantly reduced energy consumption (0.63 vs. 2.74 MJ g−1), but also is more effective in removing K and Si. For isoconversional kinetic analysis, the FWO method provides better results than the KAS method as the latter failed to fit the tree leaves sample (R2 400℃) showed that the hydrochar obtained from the MHC process has a lower average activation energy of ~190 MJ kg−1 than the conventional HC process (~260 MJ kg−1). This study reveals the potential for valorization of the landscape tree wastes via the MHC process.

The grave threat posed by food hazards to food security and human health has increased the urgency of rapid and sensitive detection. Enzyme-mimic immune detection, particularly nanozyme-activated food immunosensors (NAFI), shows distinct specificity and catalytic properties, advancing food safety supervision. However, knowledge of the fundamental principles and functionalities of NAFI is still limited. Based on tracking the timeline of the independent evolution and combination of immunosensors and nanozymes, we first provide a systemic view to describe the trends of NAFI. Moreover, the underlying catalytic mechanisms are discussed according to classification in this review, including metal-based, carbon-based, and metal-organic framework-based nanozymes. In particular, significant attention is focused on the fundamental function of nanozyme receptors in food immunosensors, including the connection between nanozymes and bio-affinity ligands (one pot and two steps), signal modulation and amplification, and various signal outputs (typical and novel modes), which are crucial for gaining the best performance and further innovation. Finally, based on representative applications of nanozymes to detect food hazards, the main challenges in the development of NAFI are summarized, and future research directions for this highly prospective frontier are envisioned.

Hen egg white lysozyme (HEWL) is frequently applied as a model protein for research on protein folding, unfolding, and fibrillization identified by featured fluorescent probes. Here, a series of hydrophilic, pH-sensitive tetraarylethene (TAE)-type AIEgens are synthesized via a geminal cross-coupling (GCC) reaction and evaluated for their capabilities of fluorescence sensing and super-resolution localization imaging of HEWL fibrils. With superior optical and sensing properties, the selected TAE-type AIEgen probe is weakly emissive in aqueous media, without dependence on the pH value and buffer concentration, but exhibits "turn-on" fluorescence upon interaction with HEWL amyloid fibrils in a spontaneous and reversible way that just meets the requirement of fluorescence random switching for super-resolution imaging. The selected probe has the strongest fluorescence response to HEWL amyloid fibrils exhibiting a limit of detection of 0.59 nmol/L and enables super-resolution fluorescence imaging of amyloid aggregates with a high resolution of 40 nm.

The nanozyme-based colorimetric strategy for heavy metal detection has broad application prospects nowadays. However, the inefficient recognition capabilities of nanozyme sensors for targets hinder its further application. Herein, the authors synthesize bare nickel selenide (NiSe

Bi2Se3 is a promising anode material for lithium-ion batteries (LIBs) due to its high capacity and weak van der Waals stacking for Li-ion insertion. However, it suffers from low conductivity and structural instability during the Li-ion insertion and extraction processes. Herein, a new carbon nanofiber (CNF) network decorated with Bi2Se3 nanoparticles (∼40 nm) was facilely prepared and directly used as a binder-free flexible anode in LIBs. The Bi2Se3/CNFs anode delivered a high reversible gravimetric capacity of 443 mA h g−1 after 260 cycles at 100 mA g−1 and a rate capability of 103 mA h g−1 at 16 A g−1. The full cell with LiCoO2 vs. Bi2Se3/CNFs has a discharge specific capacity of 261 mA h g−1 after 100 cycles at 100 mA g−1. The excellent Li-storage performance is attributed to the Bi2Se3 nanoparticles uniformly embedded in the unique conductive 3D CNFs network which effectively improves the conductivity and avoids the layer structure collapse of Bi2Se3 materials. The synergistic effect of the enhanced characteristics successfully improved the long-term cycling and rate capability of the Bi2Se3 anode. This flexible and binder-free Bi2Se3/CNFs electrode has great potential as a neoteric anode material for LIBs.

Smart materials based on photo-responsive dynamic covalent bonds have the potential for use in many applications, such as photo-modulated manipulators, actuators and self-healing materials. However, the development of high-performance multifunction visible-light-driven dynamic covalent systems has been insufficient. Herein, we report a novel linear polyurethane elastomer (HABI-PU) containing visible-light-switchable hexaarylbiimidazole (HABI) units in the polymer backbone with photo-induced scission and rapid healing capacities. When exposed to 405 nm light, the scratches on the HABI-PU film took only a few seconds to heal. More serious cut damage could be healed after exposure for 30 s and placed in the dark at room temperature for 6 h. Moreover, when a certain weight was loaded during light irradiation, the elastomers broke off as the toughness of the HABI-PU elastomers decreased. The reversible dissociation of the C–N bond of the HABI units caused the scission of long polymer chains into short chains upon light irradiation and further endowed HABI-PU with the properties of photo-induced fracture/healing. Such elastomers are promising for application in the fields of photo-controlled triggers, biomimetic systems, recycled materials, optical machining, and other engineering streams.

Supramolecular hydrogels attract extensive attention as waterborne biocompatible materials like biological tissues. Here we developed poly[N-(2-acetamidoethyl)acrylamide] (PAAE) supramolecular hydrogels with multiple hydrogen bonds, which exhibit ideal mechanical performances, such as strong resistance to compression and stretch, high stability in acidic or high ionic strength solution, excellent waterborne adhesiveness, self-healing and swelling behaviors. The small molecular precursor for PAAE hydrogels possesses great solubility up to 70 wt% in deionized water and superior infiltration capability to mouse brain tissues at 5 °C, and can be in situ polymerized at 30–45 °C and swollen in deionized water with a 1.75 times linear expansion factor. There is no noticeable loss of fluorescence intensity during the whole process from small molecular infiltration and polymerization to expansion. The mouse brain slices were embedded and used for expansion microscopy with enhanced optical resolution and preserved structure integrity.

Protein misfolding and denaturation, represented by amyloid fibrillation, are associated with many diseases. However, as a general chemical biological process, the dynamic structure information on amyloid fibrillation has not been demonstrated categorically. Herein, hen egg white lysozyme (HEWL) was used as the model protein of interest to realize in situ nanoscale imaging of protein fibrillation process using the fluorophores with aggregation-induced emission (AIE) activity. The AIE-active fluorophores exhibit the reversible capability of association and dissociation with β-sheet structure and thus dynamic binding-induced emission, which causes the spontaneous switching of fluorescence. The entire HEWL denaturation process induced by sodium dodecyl sulfate (SDS) at ambient conditions was demonstrated in detail by using two AIE-active fluorophores (TPE-NaSO3 and PD-BZ-OH) through reversible electrostatic interaction and specific labeling between AIE probes and β-sheet structures of amyloid fibrils, respectively. The results indicate that PD-BZ-OH is more specific AIE probe for amyloid fibrils than TPE-NaSO3. In comparison, the SEM and TEM results show the same denaturation process of protein fibrillation induced by SDS at different concentrations. The static super-resolution imaging of amyloid fibrils is performed with a resolution of 35 nm using PD-BZ-OH aqueous solution without additional auxiliary conditions. The dynamic evolution process of HEWL amyloid fibrillation is in situ visualized through super-resolution fluorescent microscopy with nanoscale resolution. Both static and dynamic super-resolution imaging of amyloid fibrillation provides detailed nanoscale structure information exceeding 50 nm resolution, which is of great significance in the exploration of amyloid fibrillation and related diseases.

To achieve an effective deconstruction for preparation of xylooligosaccharides (XOS) and lignin nanoparticles (LNPs) from Eucommia ulmoides, a synergistic pretreatment was successfully developed. Herein, the hemicelluloses were preferentially dissociated in acetic acid-catalyzed hydrothermal pretreatment (HTP) for preparation of XOS, and the hydrothermally-pretreated substrate was then subjected to deep eutectic solvents (DES) delignification for fabrication of LNPs. Results showed that the optimal yield (33.88% based on xylan) of XOS is obtained under the given HTP condition (170 °C, 0.5 h). NMR characterization showed that the linkages of lignin were mainly composed of β-O-4, β-β, β-5, etc. Besides, GPC analysis showed that the molecular weight of DES lignin fractions was lower (1130-1200 g/mol) than those of corresponding parent lignin fractions (8500-9620 g/mol). Further TEM characterization indicated that the optimal LNPs fraction has a narrow size distribution and the corresponding size is ranged from 60 to 110 nm. In short, the synergistic pretreatment could be used as a green and cost-effective approach for the development of bio-based chemicals and biomaterials from Eucommia ulmoides biomass.

Photocatalytic disinfection is a promising way to combat bacterial pollution in the water environment. Inefficient use of visible light and undirected diffusion of reactive oxygen species (ROS) reduce photocatalytic disinfection efficiency. Herein, inspired by the concentrating effect of convex lens, photocatalysts with particular "nano-magnifying glass effect" (TCNMgNOs) were designed by embedding magnesium oxide with "converge effect" into the tailored hierarchical triple-shell porous g-C

In this paper, the two-step activation Eucommia wood tar-based activated carbon (ETAC), cellulose nanofibers (CNF) and reduced graphene oxide (rGO) were assembled to form composite aerogel in mild condition. Impressively, the doping of optimizing ETAC greatly improved the overall specific surface area (SSA) of the aerogel, and the CNF extracted from Eucommia ulmoides wood was used to enhance the mechanical properties of graphene aerogel. Besides, the composite aerogels with high content of ETAC (67% of mass ratio) possessed efficient MnOx deposition capability (1540 mg/g), which could assemble an asymmetric free-binder supercapacitor, exhibiting an ultrahigh specific capacitance and prominent cycling stability. This work offered a feasible method to fabricate free-binder composite aerogels with excellent electrochemical property for broad applications in supercapacitors.

Biochar-based slow-release fertilizers (BSRFs) are vital for the development of eco-friendly and sustainable agriculture. Considerable attention has been given to enhancing the efficiency of fertilizers (EEFs) by appropriate modification or binding to reduce nutrient waste and improve the slow-release effect on the growth of plants. In this study, sustained binding materials were presented for BSRF synthesis, including pyroligneous acids (PA), bio-oil (BO), and modified starch binder (MSB). The results show that the release ratio of phosphorus from PA + BO+MSB was 4.7%, 15.2%, and 21.2% slower than that of PA, BO, and MSB alone, respectively. The BSRFs were characterized by SEM, XRD, FT-IR, XPS, and EDS, and the release kinetic outcome revealed that PA + BO+MSB contributed to the formation of a satisfactory structure in the BSRFs. The MSB viscosity significantly influences the slow-release performance and accumulation of N, P, and K nutrients. Moreover, economic assessments showed that PA + BO+MSB exhibited the lowest cost.

Photoswitchable fluorescent diarylethenes are promisingly widely applied in the fields of optical memory, all-optical transistors, bioimaging, and super-resolution imaging, and so on. However, they face the problems of fluorescence quenching in an aggregated/solid state, the inadequate fluorescence ON/OFF switching ratio, and the necessity of UV-light irradiation. Herein, we report a novel kind of high-performance diarylethenes with aggregated-induced emission (AIE) by conjugating two diarylethene groups on one AIE-gen (i.e., TPE-2DTE (blue-green fluorescent) and OTPE-2DTE (orange fluorescence)). Their open forms show enhanced fluorescence in the aggregated and solid states. The closed form of TPE-2DTE/OTPE-2DTE was effectively generated upon short-wavelength visible-light (400 nm-450 nm) irradiation, whose fluorescence was dramatically quenched by intra- and inter-molecular energy transfer. Remarkably, 405 nm purple irradiation gives fluorescence ON/OFF ratios of 1196:1 and 1983:1 for TPE-2DTE and OTPE-2DTE, respectively. The reverse process can be accomplished after another longer wavelength irradiation such as 621 nm and shows considerable fatigue resistance. Taking advantage of superior photoswitching properties under visible-light irradiation, TPE-2DTE and OTPE-2DTE were used for super-resolution imaging with a high resolution of sub 50 nm. This work offers guidance to design bright-emitting and high-performance visible-light-controlled diarylethene photoswitches for practical applications.

A water-soluble probe, TPA-1OH, with aggregation-induced emission activity is synthesized and used for expedient real-time fluorescence in situ visualization of latent fingerprints (LFPs). A TPA-1O...

Unprecedented dual aggregation-induced emission (AIE) behavior based on a steric-hindrance photochromic system is presented, with incorporation one or two bulky aryl groups, resulting in different flexibleness. The dual AIE behavior of open and closed isomers can be explained by restriction of intramolecular rotation (RIR), restriction of intramolecular vibration (RIV), and intermolecular stacking. The large bulky benzothiophene causes restricted rotation, enhancing the emission of open form in solution and weak π-π molecular packing, thereby efficiently enhancing the luminescence performance in the solid state. With incorporation of two large bulky benzothiophene groups, BBTE possesses the most outstanding AIE activity, undergoing highly efficient and reversible off-to-on fluorescence in film upon alternating UV and visible light irradiation along with excellent fatigue resistance. The off-to-on fluorescent photoswitch is successfully established in super resolution imaging.