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Alkyne annulation has been widely used in organic synthesis for the construction of azacycles with unique structural and physicochemical properties. However, the analogous transformation of fluoroalkynes remains a challenge and has seen limited progress. Herein we report a 1,2,3,4-tetrafunctionalization of polyfluoroalkynes for the divergent construction of 5-7-membered ( E )-1,2-difluorovinyl azacycles. The use of the fluorine atom as a detachable "activator" not only obviates the use of any transition metal catalysts and oxidizing reagents, but also ensures the [3-5 + 2]-annulation and defluorinative functionalization of fluoroalkynes with high chemo-, regio-, and stereoselectivities. This method exhibits a broad substrate scope, good functional group tolerance, and excellent scalability, providing a modular platform for accessing fluorinated skeletons of medicinal and biological interest. The late-stage modification of complex molecules, the multi-component 1,2-diamination of fluoroalkyne, and the synthesis of valuable organofluorides from the obtained products further highlight the real-world utility of this fluoroalkyne annulation technology., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Magnetostrictive CoFe 2 O 4 (CFO) nanoparticles were encapsulated within a UiO-66 metal-organic-framework layer to form a CFO@UiO-66 nanohybrid. The deforming of CFO, in response to a high-frequency AC magnetic field, initiates the piezocatalytic property of UiO-66 to generate ˙OH radicals, which can kill cancer cells buried in thick tissues, showcasing bright potential for deep-seated tumor treatment.

Ventilator-associated pneumonia (VAP) is a prevalent disease caused by microbial infection, resulting in significant morbidity and mortality within the intensive care unit (ICU). The rapid and accurate identification of pathogenic bacteria causing VAP can assist clinicians in formulating timely treatment plans. In this study, we attempted to differentiate bacterial species in VAP by utilizing the volatile organic compounds (VOCs) released by pathogens. We cultured 6 common bacteria in VAP in vitro , including Acinetobacter baumannii , Enterobacter cloacae , Escherichia coli , Pseudomonas aeruginosa , Stenotrophomonas maltophilia , and Staphylococcus aureus , which covered most cases of VAP infection in clinic. After the VOCs released by bacteria were collected in sampling bags, they were quantitatively detected by a proton transfer reaction-mass spectrometry (PTR-MS), and the characteristic ions were qualitatively analyzed through a fast gas chromatography-proton transfer reaction-mass spectrometry (FGC-PTR-MS). After conducting principal component analysis (PCA) and analysis of similarities (ANOSIM), we discovered that the VOCs released by 6 bacteria exhibited differentiation following 3 h of quantitative cultivation in vitro . Additionally, we further investigated the variations in the types and concentrations of bacterial VOCs. The results showed that by utilizing the differences in types of VOCs, 6 bacteria could be classified into 5 sets, except for A. baumannii and E. cloacae which were indistinguishable. Furthermore, we observed significant variations in the concentration ratio of acetaldehyde and methyl mercaptan released by A. baumannii and E. cloacae. In conclusion, the VOCs released by bacteria could effectively differentiate the 6 pathogens commonly associated with VAP, which was expected to assist doctors in formulating treatment plans in time and improve the survival rate of patients.

In this study, we have fabricated a dual-signal sensor for H 2 O 2 determination based on 2D Cu-MOFs decorated with Ag NPs. A novel polydopamine (PDA) reduction method was utilized to reduce [Ag(NH 3 ) 2 ] + to highly dispersed Ag NPs in situ without other reductive agents, and Cu-MOF@PDA-Ag was obtained. For the electrochemical sensor, the Cu-MOF@PDA-Ag modified electrode exhibits outstanding electrocatalytic properties toward H 2 O 2 reduction with a high sensitivity of 103.7 μA mM -1 cm -2 , a wide linear range from 1 μM to 35 mM and a low detection limit of 2.3 μM (S/N = 3). Moreover, the proposed sensor shows good feasibility in an orange juice sample. For the colorimetric sensor, colorless 3,3',5,5'-tetramethylbenzidine (TMB) can be oxidized by the Cu-MOF@PDA-Ag composite in the presence of H 2 O 2 . A Cu-MOF@PDA-Ag catalysis-based colorimetric platform is further established for the quantitative analysis of H 2 O 2 ranging from 0 to 1 mM with a lower detection limit of 0.5 nM. Importantly, such a dual-signal method for the detection of H 2 O 2 could potentially have wide practical applications.

Iron-dependent accumulation of reactive oxygen species (ROS) and lipid peroxidation play key roles in ferroptosis, which has been an attractive strategy to kill tumor cells. However, the rapid annihilation of hydroxyl radicals (˙OH) produced from the Fenton reaction has become a major obstacle in inducing lipid peroxidation in cells. In this study, we develop a nano-delivery system of unsaturated phospholipid (Lip) and polyacrylic acid (PAA) functionalized FeOCl nanosheets (FeOCl@PAA-Lip). In this system, the ˙OH radicals produced from the Fenton reaction between FeOCl nanosheets and endogenous H 2 O 2 of tumor cells attack Lip on the nanosheets in situ to initiate the lipid peroxidation chain reaction, which not only realizes free radical conversion but also leads to the amplification of ROS and lipid peroxides, thus enhancing tumor ferroptosis. The in vitro and in vivo results confirmed that FeOCl@PAA-Lip nanosheets exhibited specific tumor cell-killing effects, good biocompatibility, long circulation time, low side effects, high tumor targeting and an excellent tumor inhibition rate (73%). The Lip functionalization strategy offers a paradigm of enhancing ferroptosis treatment by conversion of ˙OH/phospholipid radicals/lipid peroxyl radicals and strengthening lipid peroxidation.

Ferroptosis induced by iron-dependent accumulation of lipid peroxides (LPOs) has received increasing attention in cancer therapy, especially chemodynamic therapy (CDT). However, the quick annihilation of hydroxyl radicals (˙OH) severely restricts the ˙OH/LPO conversion efficiency, which has become one of the key factors that influences the therapeutic efficacy of ferroptosis-based CDT. Herein, we designed a ˙OH/LPO nano-converter with a high LPO generation efficiency via loading ferrocene (Fc), a green Fenton catalyst, in the phospholipid bilayer of liposome-PEG (Fc-Lp-PEG). Under catalysis with Fc, the over-expressed H 2 O 2 in tumors can be decomposed to ˙OH. The generated ˙OH in situ reacts with unsaturated lipids on the liposome, and is converted into LPOs, which spread the lipid peroxidation chain reaction to the remote membranes of cells and organelles, triggering efficient cancer cell ferroptosis. Systematic in vitro and in vivo therapeutic outcomes showed the high tumor inhibition ratio (74.0%) and the low side effects of Fc-Lp-PEG on 4T1 tumor-bearing mice. This novel strategy for improving the ˙OH/LPO conversion efficiency might provide new insights for the clinical development of ferroptosis-based CDT.

In this study, we fabricated a novel non-enzymatic glucose sensor based on prism-like bimetallic alkaline carboxylate (CoNi-MIM). The morphology and structure of CoNi-MIM were carefully investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The electrochemical glucose oxidation of the synthesized sensor was then explored by cyclic voltammetry (CV) and chronoamperometry in alkaline medium. It was found that CoNi-MIM is the optimal choice with a remarkably high sensitivity of 5024.4 μA mM -1 cm -2 , low detection limit of 56.1 nM (S/N = 3), linear response of up to 14.3 mM and excellent selectivity compared to Co-MIM, CoFe-MIM and CoMn-MIM. Furthermore, the as-fabricated sensor demonstrated appreciable practicality for the determination of glucose in real samples. These results indicate that CoNi-MIM holds a good application prospect in non-enzymatic glucose sensing.

We report an electrochemical non-enzymatic method for hydrogen peroxide (H 2 O 2 ) detection based on Ag nanoparticle-decorated MoSe 2 (Ag/MoSe 2 -500) hybrid nanostructures. These hybrid nanocomposites are easily prepared by in situ reduction of Ag + on the surface of MoSe 2 . Benefiting from the strong synergy of Ag nanoparticles and MoSe 2 nanosheets in enhancing electrical conductivity, the Ag/MoSe 2 -500 hybrid nanostructures perform excellent sensing activity for H 2 O 2 electrocatalytic reduction with a wide linear range of 0.02-15.2 mM, a high sensitivity of 400.0 μA mM -1 cm -2 and a low detection limit of 0.39 μM (S/N = 3). Furthermore, the sensor displays satisfactory reproducibility and stability and is applicable for practical quantitative analysis of H 2 O 2 in milk and orange juice samples. In a word, Ag/MoSe 2 -500 nanocomposites are promising candidates for non-enzymatic H 2 O 2 sensing in the fields of biology and food science.

Few methods are known for the synthesis of nitroindole derivatives. A simple and practical Cs 2 CO 3 -promoted method for the synthesis of 6-nitroindole derivatives from enaminones and nitroaromatic compounds has been developed. Two new C-C and C-N bonds were formed in a highly regioselective manner under transition metal-free conditions.

Hollow prism-like NiCo 2 S 4 materials (NiCo 2 S 4 HNPs) were successfully fabricated by a two-step method. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and powder X-ray diffraction (XRD) confirmed the morphology and structure of the as-prepared NiCo 2 S 4 nanoprisms. A non-enzymatic sensor based on NiCo 2 S 4 HNPs was constructed with outstanding electrochemical activity towards glucose oxidation in alkaline medium. The sensor showed a rapid response time (∼0.1 s), a high sensitivity of 82.9 μA mM -1 cm -2 , a wide linear range (0.005-20.2 mM) and a detection limit of 0.8 μM (S/N = 3) with a good selectivity and reproducibility. Additionally, the proposed electrode also confirmed the feasibility in practical blood serum. These results indicate that NiCo 2 S 4 /ITO has great potential in the development of non-enzymatic glucose sensor applications.

In bone tissue, nerves are primarily located in the periosteum and play an indispensable role in bone defect repair. However, most bone tissue engineering approaches ignored the reconstruction of the nerve network. Herein, we aimed to develop a bilayer hydrogel simulating periosteum-bone structure to induce innervated bone regeneration. The bottom "bone" layer consisted of gelatin methacryloyl (GelMA), poly(ethylene glycol) diacrylate (PEGDA), and nano-hydroxyapatite (nHA), whereas the upper "periosteum" layer consisted of GelMA, sodium alginate (SA) and MgCl2. The mechanical properties of the upper and bottom hydrogels were designed to be suitable for neurogenesis and osteogenesis, respectively. Besides, Mg2+ from the "periosteum" layer released at the early stage (within 7 d), which aligned with the optimal time window for nerve regeneration and osteogenic related neuropeptide release. Simultaneously, the prevention of long-term Mg2+ release (after 7 d) could avoid osteogenic inhibition caused by prolonged Mg2+ exposure. Additionally, the incorporation of nHA in the bottom "bone" layer supported the long-term osteogenesis due to its osteoconductivity and slow degradation. In vitro biological experiments revealed that the bilayer hydrogel (GS@Mg/GP@nHA) promoted neurite growth and calcitonin gene-related peptide (CGRP) expression in rat dorsal root ganglion (DRG) neurons, as well as the osteogenesis of rat bone-derived mesenchymal stem cells (BMSCs). Moreover, the in vivo experiments demonstrated that the GS@Mg/GP@nHA hydrogel efficiently promoted nerve network reconstruction and bone regeneration of rat calvarial bone defects. Altogether, the bilayer hydrogel GS@Mg/GP@nHA could promote innervated bone regeneration, providing new insights for biomaterial design for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Bacterial infection severely limits the effectiveness of biomaterials for tissue repair, posing a major challenge to modern medicine. Despite advances in novel antibiotics and their application in treatment, challenges remain in clinical practice. To address this issue, biomaterials are engineered to achieve desirable anti-infective performance and compatibility via adjusting their surface physicochemical properties. Recently, numerous studies on piezoelectric materials have been performed for anti-infective and regenerative therapies, but a comprehensive review is still lacking. This article provides a brief overview of the different types of piezoelectric materials and their characteristics. Building on this understanding, this review highlights the antibacterial mechanisms including orchestrating electric field and optimizing piezoelectric catalysis, which promote infective tissue regeneration, as well as discusses the anti-infective bioapplication of piezoelectric materials. Furthermore, this review concludes with perspectives into the challenges and future research directions of piezoelectric biomaterials. [ABSTRACT FROM AUTHOR]

In this work, we develop an in situ biomass-confined approach to fabricate an atomically dispersed Fe/NC catalyst for ORR. The acquired Fe/NC demonstrates glorious oxygen reduction reaction (ORR) activity (E1/2: 0.858 V) in alkaline media and long-term cycling stability (∼750 h) in a homemade liquid zinc-air battery. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) is an inflammatory bowel disease that predominantly impacts the colon, typically starting in the rectum. A significant characteristic of UC is its propensity to affect the distal colon, which is particularly beneficial for targeted treatments such as enemas. This localized approach ensures that the medication is delivered directly to the affected areas, resulting in minimal systemic absorption. In this research, we have formulated a novel stimuli-responsive quercetin-loaded guanosine borate supramolecular hydrogel (named GBQ hydrogel), designed to prolong the residence time of the drug and protect the ulcerated intestinal tissues. The GBQ hydrogel has exhibited excellent injectability, self-healing capabilities, and biocompatibility, rendering it an ideal candidate for enema administration. In vitro studies have highlighted its ROS/pH dual-responsive release profile, which mimics the microenvironment of intestinal inflammation. Furthermore, we assessed the efficacy of the GBQ hydrogel on dextran sulfate sodium (DSS)-induced colitis, a common animal model for UC. Our findings indicate that the GBQ hydrogel significantly reduces disease activity, mitigates oxidative stress, restores the intestinal mucosal barrier, and prevents colonic cell apoptosis. Collectively, this study underscores the therapeutic potential of the GBQ hydrogel in managing inflammatory bowel conditions and paves the way for a novel hydrogel enema-based treatment strategy for UC. [ABSTRACT FROM AUTHOR]

Brucellosis is a bacterial infectious disease caused mainly by Brucella. Transmission is mainly by contact with infected domestic or wild animals or their excreta. Clinical diagnosis of brucellosis is usually based on qualitative total antibody tests, which make it difficult to differentiate between acute and pre-existing infections. In this study, for the simultaneous detection of anti-brucellosis IgG and IgM, we innovatively developed a surface-enhanced Raman scattering (SERS)-lateral flow immunoassay (LFIA) detection system, and evaluated its performance and diagnostic effect by using clinical serum samples. The key design of this biosensor involves the preparation of two immunoprobes using two Raman spheres (R-Sphere) with distinct signals conjugated to mouse anti-human IgG and IgM, respectively. In this design, brucellosis-specific antigens are embedded in the T-line, allowing simultaneous capture of anti-brucellosis IgG and IgM in a specific binding reaction. A portable Raman instrument is used to detect the characteristic signal intensities generated by IgM and IgG on the T-line, which can then be used to analyze the target IgM and IgG antibodies. Based on the analysis of 40 clinical samples, the method has a sensitivity and specificity of 100%, and the detection time is only 15 min. The advantages of this technology are fast speed, convenient use, high sensitivity, and it can distinguish the disease course to achieve precise treatment. These features make it an ideal solution for large-scale brucellosis testing in remote and nomadic areas, where it can play a crucial role in improving public health protection. [ABSTRACT FROM AUTHOR]

Cancer is a significant global health challenge, and while chemotherapy remains a widely used treatment, its non-specific toxicity and broad distribution can lead to systemic side effects and limit its effectiveness against tumors. Therefore, the development of safer chemotherapy alternatives is crucial. Prodrugs hold great promise, as they remain inactive until they reach the cancer site, where they are selectively activated by enzymes or specific factors, thereby reducing side effects and improving targeting. However, subtle differences in the microenvironments between tumors and normal tissue may still result in unintended cytotoxicity. Bioorthogonal reactions, known for their selectivity and precision without interfering with natural biochemical processes, are gaining attention. When combined with prodrug strategies, these reactions offer the potential to create highly effective chemotherapy drugs. This review examines the safety and efficacy of prodrug strategies utilizing various bioorthogonal reactions in cancer treatment. [ABSTRACT FROM AUTHOR]

Terahertz devices play an irreplaceable role in the development of terahertz technology. However, at present, it is difficult for most natural materials to respond in the terahertz band, making the devices made of them perform poorly. In order to realize the diversity and tunability of device functions, we designed a terahertz metamaterial device composed of the thermally-induced phase change material VO2. The device structure is composed of a Au bottom layer, a SiO2 dielectric layer and a VO2 top layer. Through software simulation, we found that when T = 313 K, the device has complete reflection ability in the whole terahertz band. When T = 342 K, the average absorptivity is above 95% in the ultra-wide band range of 4.71–9.41 THz, and the absorptivity reaches an amazing 0.99999 at 6.31 THz. Thus, the maximum thermal modulation range of the device is 0.001–0.99999. The Bruggeman effective medium theory clarifies the phase transition characteristics of vanadium dioxide. The Drude model establishes the functional relationship between the conductivity of vanadium dioxide and temperature. The basic principle of high absorption was described using the impedance matching theory. We also drew the electric field intensity diagram during the temperature rise of the device to further confirm the reason for the change in the device performance. In addition, the influence of the absence of different structural layers on the absorptivity was simulated, which reflected the role of each layer structure more intuitively. We also explored the influence of the geometric size of the device on the absorptivity, which provided a certain reference value for practical application. In short, we have designed a tunable terahertz device with simple structure, high absorptivity, and wide absorption bandwidth, which can be used in the fields of energy collection, electromagnetic stealth, and modulation. [ABSTRACT FROM AUTHOR]

Metamaterial absorbers show great potential in many scientific and technological applications by virtue of their sub-wavelength and easy-to-adjust structure, with bandwidth as an important standard to measure the performance of the absorbers. In this study, our team designed a new broadband absorber, which consists of an indium arsenide (InAs) disk at the top, a zinc selenide (ZnSe)-chromium (Cr) stacked disk in the middle and a metal film at the bottom. Simulation results show that the absorber has remarkable absorptivity properties in the mid-long infrared band. In a wavelength range of 5.71–16.01 μm, the average absorptivity is higher than 90%. In the band of 5.86–15.49 μm, the absorptivity is higher than 95%. By simulating the electromagnetic field diagram at each resonant frequency, the reason for high broadband absorptivity is obtained. We also constructed Poynting vector diagrams to further elucidate this phenomenon. Next, we analyzed the influence of different materials and structural parameters on absorptivity properties and tested spectral response at different polarization angles and oblique incidence of the light source in the TM and TE modes. When the source is normally incident, the absorber shows polarization insensitivity. When the angle is 40°, absorptivity is still high, indicating that the absorber also possesses angle insensitivity. The broadband absorber proposed by us has good prospects in infrared detection and thermal radiators. [ABSTRACT FROM AUTHOR]

To meet the United Nations' sustainable development goal of affordable and clean energy, there has been a growing need for low-cost, green, and safe energy storage technologies. High-field and energy-density capacitors have gained substantial attention from academics and industry, particularly for power electronics, where they will play a key role in optimising the performance of management systems in electric vehicles. The key figure of merit, energy density (Wrec), for high-field applications has dramatically increased year-on-year from 2020 to 2024, as evidenced by over 250 papers, demonstrating ever larger Wrec values. This review briefly introduces the background and principles of high energy density ceramics, but its focus is to provide constructive and comprehensive insight into the evaluation of Wrec, Emax, ΔP, and η, and more importantly, the normalised metrics, Wrec/Emax and Wrec/ΔP in lead-free dielectric ceramics. We also present several optimisation strategies for materials modification and process innovation that have been recently proposed before providing perspectives for the further development of high-field and high-energy density capacitors. [ABSTRACT FROM AUTHOR]

The metal–support interaction of heterogeneous catalysts has garnered significant attention due to its role in boosting electrocatalytic efficiency. Herein, we synthesized uniformly dispersed Pt nanoparticles decorated on a MoOx support by an ultrafast flash joule heating method. This method enables the simultaneous loading of metal and modification of support structures in a controllable, ultrafast manner. The optimal catalyst demonstrates exceptional performance in the hydrogen evolution reaction (HER) under acidic conditions, characterized by a low overpotential of only 55.08 mV to achieve a current density of 100 mA cm−2, a Tafel slope of 19.94 mV dec−1, and a significant mass activity of 13.80 A mgPt−1 at 50 mV vs. RHE. In addition, the optimal catalyst exhibits better stability for the HER than a commercial 20 wt% Pt/C catalyst. The spectroscopic characterization confirms the charge transfer between the metal and support, leading to a near-zero valence state of Pt in the optimal catalyst. Density functional theory calculations further corroborate that the metal–support interaction between Pt and MoOx leads to a suitable hydrogen adsorption free energy at the interfacial Pt site, which results in accelerating the reaction kinetics of the HER. This work aims to design and develop a metal–support heterostructure with high HER activity and stability, and provides a strategy for engineering crystalline structures and electronic configurations using an ultrafast flash Joule heating synthesis method. [ABSTRACT FROM AUTHOR]

The singlet and triplet excited states of three iodine substituted BODIPY dyes differing by their substituents (-phenyl, -phenylOH and -phenylNO2) at the meso position of the BODIPY core (BOD) are investigated using (TDA)-TDDFT and DLPNO-STEOM-CCSD calculations. An assessment of hybrid (B3LYP and MN15) and double hybrid (SOS-PBE-QIDH and SOS-oPBEPP86) exchange-correlation functionals is performed with respect to the DLPNO-STEOM-CCSD method for four types of transitions, namely ΠBOD --> Π BOD, ΠΠhenyl --> Π BOD, ΠBOD --> Π Πhenyl and ΠBOD --> s Iodine. It is found that MN15 and SOSΠBE-QIDH Πrovide a balanced descriΠtion of the excited state energies when comΠared to the DLΠNOSTEOM-CCSD results. An investigation of the effects of the solvent (dichloromethane), of the substituent and of geometrical relaxation in the excited states is then Πerformed. In Πarticular, the study discusses the Πossibility of ΠoΠulating charge transfer states (ΠΠhenyl --> Π x BOD and ΠBOD --> Π x Πhenyl) following Πhotoexcitation in the first and second absorΠtion bands in these systems. [ABSTRACT FROM AUTHOR]

Humidity sensors, serving as essential electronic components for monitoring humidity levels, show widespread applications in environmental and human body related humidity detection. The development of nanomaterials has provided numerous opportunities in many fields, including humidity sensors. Electrospinning, as a simple technique for fabricating nanofibers, has garnered increasing attention in the field of electronics. Among them, electrospun nanofibers have shown promising prospects in high-performance humidity sensors due to their large specific surface area and high porosity. After years of development, although significant achievements have been made in electrospun nanofiber-based humidity (ENH) sensors, many challenges still exist in this field. This review article aims to systematically discuss the latest developments in ENH sensors. Firstly, we provide a comprehensive overview of the fundamentals of the electrospinning technique and humidity sensors. Secondly, the research progress of ENH sensors based on different materials (polymer nanofibers, oxide nanofibers, and composite nanofibers) and device types/working mechanisms (resistance, capacitance, impedance, frequency, and voltage/power generation) is reviewed and discussed. Thirdly, the emerging applications of ENH sensors in human body related humidity detection are discussed. Finally, the challenges and future development trends of ENH sensors are analyzed from different aspects. We hope that this review will offer valuable insights and guidance for future research on ENH sensors. [ABSTRACT FROM AUTHOR]

In this paper, we propose a multiband adjustable metamaterial absorption device based on a Dirac semimetal (BDS) AlCuFe and a thermally controlled phase-change material VO2. The absorption device has an axially symmetric structure, resulting in polarization-independent characteristics, and when VO2 is in a high-temperature metal state, ultra-high absorption rates and sensitives at frequencies of M1 = 2.89 THz, M2 = 7.53 THz, M3 = 7.97 THz, and M4 = 9.02 THz are achieved. Using a parameter inversion method, we calculated the impedance of the absorber, proving that it achieves impedance matching and produces perfect absorption in the resonance region. Additionally, we changed the physical and chemical parameters of the absorption device, demonstrating the device's excellent tunability and manufacturing tolerance. Furthermore, by lowering the temperature of VO2 to that of a low dielectric state, additional resonant peaks with ultra-high absorption rates at frequencies M5 = 5.62 THz, M6 = 7.16 THz, M7 = 7.64 THz, and M8 = 8.80 THz were obtained, broadening the absorption band of the device. Lastly, we investigated the detection sensitivity of the device by changing the external refractive index, resulting in a maximum sensitivity of 2229 GHz RIU−1. To sum up, the absorption device has great application potential in the fields of communication, sensing, temperature detection and photoelectric instruments. [ABSTRACT FROM AUTHOR]

The issue of heat accumulation caused by the low thermal conductivity (TC) of polymers widely used in electronic devices has become a block for chip development. Enhancing the overall TC by adding high-TC fillers to polymers to create composites is considered one of the promising solutions. However, adding a single filler to the polymer may lead to issues such as high interfacial thermal resistance between fillers. Here, we developed a boron nitride@carbon particle (BN@C) hybrid filler by in situ growth of carbon particles on the surface of BN and constructed BN@C/epoxy composites. The presence of carbon bridged the BN and prevented its agglomeration, forming a smooth and efficient thermal conduction network. Consequently, the TC of the composite reached 1.69 W m−1 K−1 at a 60 wt% load. Additionally, it exhibited excellent thermal stability, mechanical and dielectrical properties, and breakdown strength. This study provides an effective strategy for manufacturing high-TC polymeric composites for electronic devices. [ABSTRACT FROM AUTHOR]

Forged products are widespread in the market and there is an immediate need to counter this growing menace. Anti-counterfeit techniques using fluorescent materials with covert features that appear hidden under daylight and display characteristic fluorescence upon specific source irradiation have gained popularity. Carbon dots (CDs) that can be prepared through facile synthesis from various raw materials are a class of fluorescent materials that provide tremendous opportunities to combat counterfeiting. This work focuses on the fabrication of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) derived CDs via the solvothermal approach and their subsequent purification using column chromatography. The fifth fraction obtained exhibited remarkable yellow emission (λem = 540 nm) with a high fluorescence quantum yield of 53.22% and a lifetime of 4 ns. The CDs appeared quasi-spherical during TEM imaging with an average diameter of 1–3 nm and appeared polycrystalline from the SAED pattern. The XPS and TEM-EDS results suggested carbon as the major element along with oxygen and nitrogen as the other heteroatoms. The water-based ecofriendly ink formulated using the CDs was printed on UV dull paper using the flexography technique. The print-proof paper samples appeared pale pink under daylight and fluorescent yellow upon 365 nm UV illumination. Moreover, the stability of the print was confirmed upon exposure to strong UV radiation cycles and abrasion resistance. Besides, the fluorescence emission remained unaltered even after 5 months of storage under room temperature conditions. The ink was used to print on PVC sheets and FBB boards with good stability against scuffing, suggesting its applicability in the packaging industry. The CDs could also serve as fluorescent markers for identifying post-consumer plastic packaging for a circular economy. [ABSTRACT FROM AUTHOR]

A series of six DPP-based organic small molecule photovoltaic donor materials were designed and synthesized successfully. The targeted structural design and regulation of the materials were carried out in three steps. Firstly, the introduction of a π-bridge in the molecule enhances the intramolecular charge transfer (ICT) effect and improves the short-circuit current (Jsc) of the device. Secondly, different end groups were introduced to adjust the energy levels of molecules, to obtain more matching donor materials for acceptor materials. Finally, the molecular configuration was adjusted to meet the requirements of increasing the open circuit voltage (Voc). It is worth mentioning that for the end group regulation strategy, a small molecule donor was synthesized, in which fluorene-capped triarylamine as the electron-donating unit provided a reference for the future development of related donor materials. To our knowledge, the selection of triphenylamine and phenyl-carbazole as central nuclei for double-armed small molecule donors has been rarely reported. In this work, triphenylamine and phenyl-carbazole were used as the central nuclei of the A–π–D–π–A type molecular configuration, resulting in lower HOMO energy levels and higher Voc. As a result, without further optimization of the devices, the power conversion efficiency (PCE) of the photovoltaic device based on (DPP)2TPA was more than three times that of a previously reported device based on TPA-DPP-TPA, and the PCE of the device based on (DPP)2PCZ was more than twice that of a previously reported device based on SM1. Our work demonstrates that optimization of photovoltaic performance can be achieved through rational structural design and configuration regulation of the photovoltaic material, which provides important guidance for the development of novel photovoltaic materials in the future. [ABSTRACT FROM AUTHOR]

This highlight summarises electrochemical approaches for the deconstructive functionalization of arylcycloalkanes via the fragmentation of anodically generated aromatic radical cations. A diverse range of deconstructive functionalization processes is described, including discussion on the electrochemical reaction conditions employed, scope and limitations, and reaction mechanisms, in addition to highlighting future opportunities in this burgeoning area of sustainable synthesis. [ABSTRACT FROM AUTHOR]

The emergence of Y6 and its derivatives has significantly advanced organic photovoltaics (OPVs). However, the limited design strategies for Y6-based non-fullerene acceptors (NFAs) in absorbing visible light restrict their application in indoor OPVs (IOPVs). Furthermore, the reliance on additive-assisted chlorinated solvents for processing photoactive layers poses a significant barrier to IOPV commercialization. Herein, we synthesized two IPC-ended NFAs (IPC-BBO-IC2F and IPC-BBO-IC2Cl) and two IPC1CF3-ended NFAs (IPC1CF3-BBO-IC2F and IPC1CF3-BBO-IC2Cl). These asymmetric NFAs, featuring two distinct groups at the molecular ends, demonstrated blue-shifted absorption and elevated energy levels compared to Y6, offering a promising approach to harness indoor light and achieve higher open-circuit voltages more effectively. IOPVs processed without additives and using o-xylene, based on PM6:IPC1CF3-BBO-IC2F and PM6:IPC1CF3-BBO-IC2Cl, showed high efficiencies of 26.5% and 24.2%, respectively, under 1000-lux light-emitting diode (LED) illumination. These efficiencies surpass those of IOPVs that employ IPC-ended NFAs or Y6. Moreover, ternary IOPVs based on PM6:Y6:IPC1CF3-BBO-IC2F and PM6:Y6:IPC1CF3-BBO-IC2Cl achieved notable efficiencies of 26.9% and 27.1% under 1000 lux-LED illumination and 30.2% and 29.2% under 1000 lux-fluorescent light (FL) illumination, respectively. These findings underscore the potential of the IPC1CF3 end group in the asymmetric structural modification of Y6 to enhance the performance of IOPVs using additive-free and environmentally benign solvents. [ABSTRACT FROM AUTHOR]

Oxygen-ionic and proton-conducting oxides are an important class of functional materials for their applications as electrolytes in various high-temperature electrochemical cells, including solid oxide fuel cells (SOFCs), solid oxide electrolysis cells (SOECs), proton ceramic fuel cells (PCFCs), and proton ceramic electrolysis cells (PCECs). The electrolyte, as a heart of these cells, must meet a number of stringent requirements, among which its ionic conductivity is one of the most important parameters determining the possible applications in electrochemical devices and operating temperatures. In the present work, we provide a comparative analysis of the ionic conductivity for several classical electrolyte classes, such as stabilized/doped ZrO2, CeO2, LaGaO3, BaCeO3, BaZrO3, and Ba(Ce,Zr)O3. This analysis provides possible windows of conductivity variation and potential (common and specific) factors responsible for conductivity differences for the same materials and measurement conditions. In addition, the ionic conductivity is discussed not only for massive ceramic electrolytes, but also for their thin-film form in SOFCs/PCFCs or SOECs/PCECs. As a result, the transport properties of the state-of-the-art electrolytes have been revised and compared to show which system prevails over the other under different experimental conditions. Therefore, this technical review can be used as a reference source to provide useful information on oxygen-ionic and protonic conductivity for the most popular solid oxide electrolytes. [ABSTRACT FROM AUTHOR]

Bismuth sulfide (Bi2S3) is a chalcogenide semiconductor with a relatively narrow energy band gap that is promising for use in solar cells and photodetectors. This paper presents a highly efficient microwave synthesis of Bi2S3 submicrometric structures using poly(vinyl alcohol) (PVA) as a viscosity modification agent. The chemical composition, morphology, crystal structure, and optical properties of the prepared materials were investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and diffuse reflectance spectroscopy (DRS). The use of PVA in Bi2S3 synthesis resulted in a change in material morphology from microrods to nanosheets and a slight increase in the energy band gap from 1.34 eV to 1.43 eV. The Bi2S3 nanosheets were examined as photosensitive materials for the detection of visible light. High ON/OFF ratios of 66, 44, and 15 and large specific detectivities of 1.12 × 1011, 7.68 × 1010, and 6.43 × 1010 Jones were achieved under blue (468 nm, 0.52 μW cm−2), green (517 nm, 0.95 μW cm−2), and red (628 nm, 0.13 μW cm−2) light illuminations, respectively. The photosensitive properties of Bi2S3 nanosheets were remarkable compared to that of many other photodetectors based on Bi2S3 micro- and nanostructures. [ABSTRACT FROM AUTHOR]

Understanding the spatiotemporal dynamics of formaldehyde (FA) is crucial for elucidating its pathophysiology. In this study, we designed a series of organelle-resolved probes to investigate FA dynamics. By incorporating various organelle anchors into a coumarin hydrazonate, we developed a series of probes with excellent organelle selectivity and FA specificity, enabling rapid and precise sensing of FA in an organelle-resolved way. Leveraging these probes, we captured the spatiotemporal dynamics of native FA in response to exogenous FA or oxidative stress challenges. In particular, we unveiled the distinct responses of various organelles to identical cellular stressors. Moreover, we observed the dynamic response within individual organelles when cells were exposed to stressors for varying durations. We envision these probes will serve as versatile tools for probing FA pathophysiology. [ABSTRACT FROM AUTHOR]

Thio-benzothioxanthene imide (BTXI) exhibits long excited state lifetime (τT = 17.7 μs) and high ISC efficiency (ΦΔ = 97%). For the first time, BTXI derivatives were used as photosensitizers for triplet–triplet annihilation upconversion, achieving the highest efficiency of 13.8%. In addition, thio-BTXI derivatives were used as photoinitiators for photopolymerization, resulting in a series of green light-activated radical polymerization systems. [ABSTRACT FROM AUTHOR]

In situ monitoring of biological processes between different organelles upon oxidative stress is one of the most important research hotspots. Fluorescence imaging is especially suitable for biomedical applications due to its distinct advantages of high spatiotemporal resolution, high sensitivity, non-invasiveness, and in situ monitoring capabilities. However, most fluorescent probes can only achieve light-up imaging of single organelles, thus the combined use of two or more probes is usually required for monitoring biological processes between organelles, which can suffer from tedious staining and washing procedures, increased cytotoxicity and poor photostability. Exogenetic oxidants can affect broad-spectrum subcellular organelles, which are not conducive to in situ monitoring of biological processes between specific organelles. To tackle these challenges, a series of dual-/multi-organelle-targeted aggregation-induced emission (AIE) probes associated with oxidative stress have been designed and developed in the past few years. Herein, the recent progress of these AIE probes is summarized in biomedical applications, such as apoptosis monitoring, interplay between organelles, microenvironmental changes of organelles, organelle morphology tracking, precise cancer therapy, and so forth. Moreover, the further outlook for dual-/multi-organelle-targeted AIE probes is discussed, aiming to promote innovative research in biomedical applications. [ABSTRACT FROM AUTHOR]

Titanium oxide (TiO2) layers are widely used in perovskite electron transport. Owing to its excellent electron transport capability, solar cell devices containing a TiO2 layer achieve high conversion efficiency. However, the realization of highly-efficient devices on unmodified flat TiO2 is still a tricky problem. Therefore, this work changed the method of preparing TiO2 in an aqueous solution and prepared a type of TiO2 film with high Cl content on the surface and a low interface defect in contact with perovskite. It was found that this novel method achieved the highest conversion efficiency of 24.31%. This work provides a new idea for the preparation of a low-defect TiO2 electron transport layer. [ABSTRACT FROM AUTHOR]

As electronic devices advance, there's a critical need for thermal interface materials (TIMs) with high thermal conductivity and minimal thermal resistance to address thermal dissipation challenges effectively. Carbon fibers (CFs), known for their axial thermal conductivity, are ideal for creating high-performance TIMs in a vertically aligned structure, aligning with the TIMs' heat transfer direction. Despite advancements in CF alignment for improved thermal conductivity, the high thermal resistance and the need for cost-effective manufacturing remain challenges. We propose a novel sandwich structure integrating vertical heat transfer pathways with surface modification to tackle these issues. This structure features a core of vertically aligned CF composite, achieved through a rolling-press method, flanked by liquid metal-modified layers to reduce contact thermal resistance. Our composites demonstrate an exceptional through-plane thermal conductivity of 51.90 W m−1 K−1 at 73.68 wt% filler content, 323 times higher than that of the PDMS matrix, and a reduced total thermal resistance from 0.55 to 0.32 K cm2 W−1 after interface modification. This research offers insights into designing CF-based composites for enhanced thermal management, applicable in cloud computing and autonomous driving. [ABSTRACT FROM AUTHOR]

Dielectric ceramics have garnered significant attention in the realm of pulsed power system applications. Nevertheless, achieving a high recoverable energy density (Wrec) in dielectric ceramics remains challenging. Here, a high Wrec of 6.1 J cm−3 was achieved in (1 − x)(0.6Na0.5Bi0.5TiO3–0.4Sr0.7Bi0.2TiO3)–xSm2O3 relaxor ferroelectric ceramics (RFCs). The enhanced Wrec stems from two factors: (I) the incorporation of Sm3+ with a small ionic radius can increase disorder at the A-site, thereby enhancing relaxor properties and reducing remnant polarization (Pr); (II) the introduction of Sm2O3 reducing vacancy and grain size, leading to an enhanced breakdown strength (Eb) of 470 kV cm−1. This higher Eb facilitates increased maximum polarization (Pmax). The increased Eb and the large polarization difference (ΔP = Pmax − Pr) contribute to a substantial improvement in Wrec. Additionally, a novel approach was introduced to assess the relaxor characteristics by quantifying the degree of linear fitting of P–E loops. This study presents an effective strategy for designing high Wrec dielectric ceramics and introduces an innovative method for analyzing the relaxor properties of RFCs. [ABSTRACT FROM AUTHOR]

Ionic organic nonlinear optical crystals have been established as efficient terahertz (THz) wave generators with a high generated THz power and a very wide bandwidth and can also be used as ultra-broad THz detectors. In this perspective, we discuss various design strategies to obtain high-performance ionic organic THz crystals. The introduction of aromatic coulombic interaction groups and acentric head-to-tail cation–anion assembly groups, as well as the control of the van der Waals volume of aromatic ions, are common to many top-level ionic organic THz crystals. Solid-state molecular and phonon vibrations of these crystals strongly influence the characteristics of THz generation and detection, in addition to their optical and nonlinear optical properties. The THz vibrational modes depend on the chemical structure, intermolecular interaction ability, crystal structure, void volume, and crystal density of organic THz crystals. To give a perspective on the future design of optimized ionic organic THz crystals and the influence of their phonon modes on ultra-broadband THz applications, we discuss both the structural factors that influence these modes and their specific influence on THz optical properties. [ABSTRACT FROM AUTHOR]