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A direct band gap of 1.6 eV has been identified in wurtzite CoO thin films, which matches the required value to achieve a theoretically high conversion efficiency solar cell. Its p-type conduction has been determined and an intense sub-gap absorption between 0.7 and 1.1 eV has been observed. [ABSTRACT FROM AUTHOR]

Electrolyte-gated transistors hold promise for applications in printable and flexible electronics. Metal oxide semiconductors are particularly interesting as electrolyte-gated channel materials for their abundance, thermodynamic stability and ease of processing under ambient conditions. In this work, we synthesized by sol–gel and hydrothermal methods different types of tungsten oxide to be used as channel materials in ion gel-gated transistors. X-ray diffraction and scanning and transmission electron microscopy revealed that the differently processed oxides show a different structure (hexagonal and monoclinic) and morphology (granular, nanofiber and nanoplate). We studied the electrochemical and transistor properties of the oxides using, as the gating media, two different ion gels prepared from the same ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM]TFSI), and two different block copolymers. We tentatively propose that for sufficiently high values of the gate–source bias, the doping results from chemical and electrochemical contributions. [ABSTRACT FROM AUTHOR]

We investigate the polarization loss in the archetypical molecular organic ferroelectric trialkylbenzene-1,3,5-tricarboxamide (BTA). We prove that the polarization loss is due to thermally activated R-relaxation, which is a collective reversal of the amide dipole moments in ferroelectric domains. By applying a weak electrostatic field both the polarization loss and the R-relaxation are suppressed, leading to an enhancement of the retention time by at least several orders of magnitude. Alternative loss mechanisms are discussed and ruled out. By operating the thin-film devices slightly above the crystalline to liquid crystalline phase transition temperature the retention time of one compound becomes more than 12 hours even in absence of supportive bias, which is among the longest reported so far for organic ferroelectric materials. [ABSTRACT FROM AUTHOR]

This study investigates the magneto-optical response of liquid crystals (LCs) with planar anchoring in the presence of γ-Fe 2 O 3 magnetic nanoparticles (MNPs). This research demonstrates the formation of novel magnetic composite chains of LCs wrapped around γ-Fe 2 O 3 MNP chains within the LC matrix under an applied magnetic field. These composite chains exhibit a distinct magneto-optical response, characterized by changes in birefringence and dichroism as the magnetic field direction is altered. Based on experimental findings, a two-subsystem model and an effective volume fraction of composite chains are proposed to describe the magneto-optical behavior of the γ-Fe 2 O 3 MNP-doped LCs. The first subsystem comprises the LC matrix, which retains its inherent anisotropic optical properties and does not respond to the applied magnetic field. The second subsystem consists of the magnetic composite chains, which exhibit a distinct magneto-optical response due to their rotational alignment with the magnetic field. The difference in absorbance, 2 α d d , which corresponds to dichroism, decreases with increasing magnetic field angle Θ , indicating a corresponding change in dichroism. This interplay between the two subsystems leads to the macroscopic magneto-optical response observed in the γ-Fe 2 O 3 MNP-doped LCs. Due to the stability of the composite chains, the magneto-optical response is stable and can be reversed.

CsPbBr 3 perovskite quantum dots (QDs) have attracted much attention in the optical field because of their low band gap, wide absorption spectrum and high color purity. However, their poor stability in extreme environments such as water, light and heat severely limits their application in optical fields. Here, we prepared m-SiO 2 /CsPbBr 3 composite luminescent material using an aqueous phase method combined with high temperature calcination. The material can retain 87% of the initial photoluminescence quantum efficiency after 60 days of storage under ambient conditions (humidity ∼80%; temperature ∼25 °C), its photoluminescence intensity only decreased by 33% after immersion in water for 90 min. This indicates that the material retains good stability under a high humidity environment. Finally, PMMA@m-SiO 2 /CsPbBr 3 flexible films were prepared by aqueous solution polymerization. The flexible film has excellent green light emission properties and exhibits (0.092, 0.625) CIE coordinates., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this study, a targeted graphene quantum dot-cationic polymer composite gene vector with endothelial cell-targeting CAG peptide was successfully designed and prepared. This vector could efficiently bind and deliver the therapeutic gene pZNF580 to endothelial cells (HUVECs). At a concentration of less than 40 μg mL -1 , the results of the CCK-8 assay showed that the relative cell viability of each composite gene vector was greater than 80%, and the results of the flow cytometry assay showed that C-GQDs-PEI-PEG-CAG/pZNF580 (88.96%) and N-GQDs-PEI-PLGA-PEG-CAG/pZNF580 (87.70%) treated groups showed significantly higher cell viability than the positive control group Lip2000/pZNF580 (56.76%). The results of in vitro cell transfection and western blot experiments confirmed that the composite gene vector was able to deliver pZNF580 efficiently and enable the high expression of the ZNF580 protein in HUVECs. The results of the EdU assay, wound healing and Transwell experiments indicated that the composite gene vector/pZNF580 nanoparticles (NPs) could significantly promote the proliferation and migration. The results of the EdU method showed that the proliferative ability of C-GQDs-PEI-PLGA/pZNF580 (84.96 ± 1.99%) and N-GQDs-PEI-PLGA/pZNF580 (85.01 ± 1.31%) treatment groups for HUVECs was significantly higher than that of the positive control group Lip2000/pZNF580 (77.89 ± 2.18%). The results of the scratch assay showed that the cell migration rate of C-GQDs-PEI-PLGA-PEG-CAG/pZNF580 (93.08 ± 1.97%) and N-GQDs-PEI-PLGA-PEG-CAG/pZNF580 (91.99 ± 1.52%) groups was significantly higher than that of the positive control group Lip2000/pZNF580 (85.03 ± 2.21%). In addition, the results of the in vitro angiogenesis assay showed that the C-GQDs-PEI-PLGA-PEG-CAG/pZNF580 and N-GQDs-PEI-PLGA-PEG-CAG/pZNF580 groups had significantly higher angiogenesis-promoting ability than the positive control group, Lip2000/pZNF580.The present study provides a highly efficient and low-toxic method to promote endothelial cell migration in the field of regenerative medicine and a low-toxicity strategy to promote endothelial layer formation, which provides new possibilities for future vascular regeneration therapy.

To address the intrinsic limitations of both TiO 2 and MXenes, we propose an effective strategy for the engineering of a 3D Ti 3 C 2 /TiO 2 nanorod hybrid, where the in situ synthesized TiO 2 nanorods are homogeneously decorated onto the surface of 3D Ti 3 C 2 MXene via simple oxidation. As the LIB anode, it demonstrates exceptional long-term cycling stability with a specific capacity of 384.1 mA h g -1 after 600 cycles at 1.0 A g -1 .

In the quest for excellent light-structural materials that can withstand mechanical extremes for advanced applications, design and control of microstructures beyond current material design strategies have become paramount. Herein, we design a coherent shell at incoherent precipitates in the 2195 aluminum alloy with multi-step metastable phase transitions. A high local strain rate via a neoteric deformation-driven metallurgy method facilitated the diffusion of Li. The original T 1 (Al 2 CuLi) phases were transformed into coherent-shell (Li-rich) irregular-coated incoherent-core (Al 2 Cu) precipitates. The ultimate tensile strength and elongation reached 620 ± 18 MPa and 22.3 ± 2.2%, exhibiting excellent strength-ductility synergy. Grain boundaries, dislocation, solid solution atoms, and precipitates all contributed to the yield strength of the materials, among which precipitates occupied a dominant position, contributing approximately 56.07%. A new "incoherent-coherent interact" strain-hardening mechanism was also clarified, which was believed to be promoted in other heat-treatable alloy systems, especially with multi-step metastable phase transitions.

A novel sheet-like tin-based metal-organic framework exhibited a specific capacity for lithium storage as high as 1033.3 mAh g -1 at 200 mA g -1 with excellent cycling stability. This framework, due to its unique porous structure and multiple lithium storage sites, could better cope with challenges occurring during lithium insertion/extraction than could traditional tin materials.

In large-scale radiation exposure events, the ability to triage potential victims by the received radiation dosage is crucial. This can be evaluated by radiation-induced biological changes. Radiation-responsive mRNA is a class of biomarkers that has been explored for dose-dependency with methods such as RT-qPCR. However, these methods are challenging to implement for point-of-care devices. We have designed and used molecular beacons as probes for the measurement of radiation-induced changes of intracellular mRNA in a microfluidic device towards determining radiation dosage. Our experiments, in which fixed TK6 cells labeled with a molecular beacon specific to BAX mRNA exhibited dose-dependent fluorescence in a manner consistent with RT-qPCR analysis, demonstrate that such intracellular molecular probes can potentially be used in point-of-care radiation biodosimetry. This proof of concept could readily be extended to any RNA-based test to provide direct measurements at the bedside., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Carbon quantum dots (C-dots) have developed into potential nanomaterials for lighting, catalysis and bioimaging because of their excellent optical properties and good biocompatibility. However, it is still a challenge to produce efficient red emitting carbon quantum dots (R-C-dots) due to their obscure formation mechanism. This work offered a method to reveal the formation process from the precursor o -phenylenediamine ( o -PDA) to R-C-dots. Different from traditional hydrothermal reactions, R-C-dots were synthesized at relatively low temperature and ambient pressure. The pre-oxidation intermediate aminophenol played an important role in the synthesis of R-C-dots, which further cross-linked and polymerized with o -PDA in an acid environment to form R-C-dots. The obtained R-C-dots had a photoluminescence quantum yield of up to 33.26% and excellent two-photon fluorescence properties. A white light-emitting diode (WLED) based on R-C-dots as the red phosphor exhibited standard white light CIE color coordinates of (0.33, 0.33) with a correlated color temperature of 5342 K and a high color rendering index (CRI) of 94.5. The obtained rendering index is the highest value among WLEDs with color coordinates of (0.33, 0.33) based on C-dots. This work provides a new perspective for the controllable large-scale synthesis of red C-dots., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Pitaya is a well-known fruit widely cultivated in tropical and subtropical tropical regions, and is characterized by its flesh colour into red, white, and yellow pitaya. Red pitaya has dark red flesh and is the preferred choice among consumers due to its superior taste compared to other varieties. Red pitaya has been known to cause diarrhoea, and studies have reported that pitaya does this by drawing moisture into the intestines, resulting in defecation. However, the exact mechanism of action is still unclear. In this study, mass spectrometry was employed to identify small molecular compounds in red pitaya powder, and a loperamide hydrochloride-induced early constipation mouse model was used to assess the efficacy of red pitaya. 16S rDNA and non-targeted metabolomics techniques were used to systematically reveal the regulatory characteristics of the intestinal flora and to identify the intestinal metabolites associated with constipation. The results showed that 44 novel small molecular compounds were identified from red pitaya powder, including a variety of phenolic acids and flavonoids. Pathological results showed that administration of red pitaya powder at a high dose (1000 mg kg -1 ) significantly ameliorated the abnormal expansion of intestinal goblet cells observed in the early stages of constipation. In addition, early constipation increased metabolites such as serotonin and 5-hydroxytryptophol, which were normalized following the ingestion of red pitaya powder. Furthermore, Erysipelatoclostridium , Parasutterella , and other abnormal gut microbiota associated with early constipation returned to healthy levels after the ingestion of red pitaya powder. Finally, significant correlations were observed between the expression of 33 different serum metabolites and the abundance of eight kinds of intestinal flora. Consequently, red pitaya holds potential as a safe food supplement for the prevention or amelioration of early-stage constipation.

Exposure to food allergens elicits fast changes in the intestinal microenvironment, which guides the development of allergic reactions. Investigating the key information about these changes may help in better understanding food allergies. In this research, we explored the relationship between a food allergy and extracellular adenosine triphosphate (ATP), a danger molecule that has been proved to regulate the onset of allergic asthma and dermatitis but has not been studied in food allergies, by developing a unique animal model through allergen-containing diet feeding. After consuming an allergen-containing diet for 7 days, the allergic mice exhibited severe enteritis with elevated luminal ATP levels. The dysregulated luminal ATP worsened food-induced enteritis by enhancing Th17 cell responses and increasing mucosal neutrophil accumulation. In vitro experiments demonstrated that ATP intervention facilitated Th17 cell differentiation and neutrophil activation. In addition, the diet-induced allergy showed noticeable gut dysbiosis, characterized by decreased microbial diversity and increased diet-specific microbiota signatures. As the first, we show that food-induced enteritis is associated with an elevated concentration of luminal ATP. The dysregulated extracellular ATP exacerbated the enteritis of mice to a food challenge by manipulating intestinal Th17 cells and neutrophils.

A novel processing method combining short-time ozone pretreatment with hydrolysis has been developed to reduce whey protein allergenicity. The results showed that ozone treatment altered the whey protein spatial structure, initially increasing the surface hydrophobicity index, and then decreasing due to polymer formation as the time increased. Under the optimized conditions of alkaline protease-mediated hydrolysis, a 10-second pre-exposure to ozone significantly promoted the reduction in the IgE binding capacity of whey protein without compromising the hydrolysis efficiency. Compared with whey protein, the degranulation of KU812 cells stimulated by this hydrolysate decreased by 20.54%, 17.99%, and 22.80% for IL-6, β-hexosaminidase, and histamine, respectively. In vitro simulated gastrointestinal digestion confirmed increased digestibility and reduced allergenicity. Peptidomics identification revealed that short-time ozonation exposed allergen epitopes, allowing alkaline protease to target these epitopes more effectively, particularly those associated with α-lactalbumin. These findings suggest the promising application of this processing method in mitigating the allergenicity of whey protein.

A vertically-stacked MXene/rGO composite membrane with ultrashort transport channels is reported here, which demonstrated outstanding molecular sieving, i.e. , H 2 /CO 2 selectivity of up to 83 together with high H 2 permeance of 2.7 × 10 -7 mol m -2 s -1 Pa -1 at 120 °C, highlighting its applicability for H 2 /CO 2 separation in CO 2 capture and sequestration.

The inability to systemic administration of nanoparticles, particularly cationic nanoparticles, has been a significant barrier to their clinical translation due to toxicity concerns. Understanding the in vivo behavior of cationic lipids is crucial, given their potential impact on critical biological components such as immune cells and hematopoietic stem cells (HSC). These cells are essential for maintaining the body's homeostasis, and their interaction with cationic lipids is a key factor in determining the safety and efficacy of these nanoparticles. In this study, we focused on the cytotoxic effects of cationic lipid/DNA complexes (CLN/DNA). Significantly, we observed that the most substantial cytotoxic effects, including a marked increase in numbers of long-term hematopoietic stem cells (LT-HSC), occurred 24 h post-CLN/DNA treatment in mice. Furthermore, we found that CLN/DNA-induced HSC expansion in bone marrow (BM) led to a notable decrease in the ability to reestablish blood cell production. Our study provides crucial insights into the interaction between cationic lipids and vital cellular components of the immune and hematopoietic systems.

Fluoride pollution in water has garnered significant attention worldwide. The issue of fluoride removal remains challenging in areas not covered by municipal water systems. The industrial aluminum electrode and natural bauxite coordinated defluorination system (IE-BA) have been employed for fluoride removal. The experiment investigated the effects of pH, current density, and inter-electrode mineral layer thickness on the defluorination process of IE-BA. Additionally, the study examined the treatment efficiency of IE-BA for simulated water with varying F - concentrations and assessed its long-term performance. The results demonstrate that the defluorination efficiency can reach 98.4% after optimization. Moreover, irrespective of different fluoride concentrations, the defluorination rate exceeds 95.2%. After 72 hours of continuous operation, the defluorination rate reached 91.9%. The effluent exhibited weak alkalinity with a pH of around 8.0, and the voltage increased by 2.0 V compared to the initial moment. By analyzing the characterization properties of minerals and flocs, this study puts forward the possible defluorination mechanism of the IE-BA system. The efficacy of the IE-BA system in fluoride removal from water was ultimately confirmed, demonstrating its advantages in terms of defluorination ability under different initial conditions and resistance to complex interference. This study demonstrates that the IE-BA technology is a promising approach for defluorination., Competing Interests: The authors declare that they have no competing financial interests or personal relationships that may have influenced the work reported in this study., (This journal is © The Royal Society of Chemistry.)

Activity-based ubiquitin probes (Ub-ABPs) have recently been developed as effective tools for studying the capabilities of E1-E2-E3 enzymes, but most of them can only be used in cell lysates. Here, we report the first cell-penetrating Ub-Dha probes based on thiazolidine-protected cysteines, which enable successful delivery into cells confirmed by a fluorophore at the N-terminus of Ub and live-cell fluorescence microscopy. A total of 18 E1-E2-E3 enzymes in live cells were labelled and enriched in combination with label-free quantification (LFQ) mass spectrometry. This work provided a new cell-penetrating Ub tool for studying the activity and function of Ub-related enzymes.

Efforts to enhance the efficiency of electrocatalysts for the oxygen reduction reaction (ORR) in energy conversion and storage devices present formidable challenges. In this endeavor, M-N 4 -C single-atom catalysts (MN 4 ) have emerged as promising candidates due to their precise atomic structure and adaptable electronic properties. However, MN 4 catalysts inherently introduce oxygen functional groups (OGs), intricately influencing the catalytic process and complicating the identification of active sites. This study employs advanced density functional theory (DFT) calculations to investigate the profound influence of OGs on ORR catalysis within MN 4 catalysts (referred to as OGs@MN 4 , where M represents Fe or Co). We established the following activity order for the 2eORR: for OGs@CoN 4 : OH@CoN 4 > CoN 4 > CHO@CoN 4 > C-O-C@CoN 4 > COC@CoN 4 > COOH@CoN 4 > CO@CoN 4 ; for OGs@FeN 4 : COC@FeN 4 > CO@FeN 4 > OH@FeN 4 > FeN 4 > COOH@FeN 4 > CHO@FeN 4 > C-O-C@FeN 4 . Multiple oxygen combinations were constructed and found to be the true origin of MN 4 activity (for instance, the overpotential of 2OH@CoN 4 as low as 0.07 V). Furthermore, we explored the performance of the OGs@MN 4 system through charge and d-band center analysis, revealing the limitations of previous electron-withdrawing/donating strategies. Machine learning analysis, including GBR, GPR, and LINER models, effectively guides the prediction of catalyst performance (with an R 2 value of 0.93 for predicting Δ G *OOH_vac in the GBR model). The E g descriptor was identified as the primary factor characterizing Δ G *OOH_vac (accounting for 62.8%; OGs@CoN 4 : R 2 = 0.9077, OGs@FeN 4 : R 2 = 0.7781). This study unveils the significant impact of OGs on MN 4 catalysts and pioneers design and synthesis criteria rooted in E g . These innovative findings provide valuable insights into understanding the origins of catalytic activity and guiding the design of carbon-based single-atom catalysts, appealing to a broad audience interested in energy conversion technologies and materials science.

The aim of this work was to evaluate the ameliorative effects of exosome biogenesis in cow's milk allergy (CMA) response. In this context, BALB/c mice were systemically sensitized with cow's milk proteins plus an aluminum adjuvant to induce CMA. The inhibitor GW4869 of exosome biogenesis was added before sensitization and then the anaphylactic reactions were evaluated both in vivo (clinical score and body temperature) and in vitro (serum histamine, allergen-specific antibodies, cytokines by ELISA and cell analysis by flow cytometry) to explore the role of exosomes in the development of CMA. Nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM) showed that the size distribution and morphology of CMA-derived exosomes were not changed after GW4869 preconditioning, and the concentration of exosomes was much lower than that of the CMA group. In the GW4869 group, inhibition of release of exosomes modulated the induction of T helper 2 cell (Th2)-related substances, with a decrease in histamine and allergen-specific immunoglobulin (Ig) E, and the expression of Th1, Th2, and Th17 cells all decreased as well. Moreover, the experimental data were integrated by means of principal component analysis (PCA) to give an overview that the percentage of Th cells and concentrations of cytokines were more influenced by GW4869 treatment. These data for the first time demonstrated that exosomes are involved in the development of CMA and the blockade of exosome release with GW4869 suppressed the IgE-mediated immune response in CMA.

Cationic copolymers are widely used in gene delivery as a non-viral gene vector, but their applications are limited by low transfection efficiency and high cytotoxicity. In order to enhance the transfection efficiency of copolymer micelles to endothelial cells (HUVECs) and reduce their cytotoxicity, this study synthesized an amphipathic multi-targeted copolymer micelle delivery system PCLMD-PPEGMA-NLS-TAT-REDV (TCMs). Gel test results showed that TCMs showed good pZNF580 binding ability and could effectively load the pZNF580 plasmid. The CCK-8 results show that when the concentration of TCMs is greater than 60 μg mL -1 , it will affect cell viability and have low cytotoxicity. We found that the multi-targeted copolymer micelles can be effectively taken up by HUVECs in vitro . The transfection efficiency of TCMs@pZNF580 (w/w pZNF580 = 3) to HUVECs was comparable to that of the positive control group lip2000@pZNF580, and WB also showed the same trend. In addition, the TCMs@pZNF580 complex also significantly enhanced the proliferation and migration of HUVECs. The experimental results on blood vessel formation showed that TCMs@pZNF580 accelerated the vascularization of HUVECs. This experiment provided a new technology platform for targeted gene therapy, especially for endothelialization and vascularization. The research results have important reference value for the treatment of cardiovascular diseases.

Molybdenum dioxide (MoO 2 ) has been considered as a promising hydrogen evolution reaction (HER) electrocatalyst. However, the active sites are mainly located at the edges, resulting in few active sites and poor activity in the HER. Herein, we first reported on an efficient strategy to incorporate Fe into MoO 2 nanosheets on Ni foam (Fe-MoO 2 /NF) using a rapid carbothermal shocking method (820 °C for 127 s). Notably, the different spin states between Fe and Mo atoms could lead to rich lattice dislocations in Fe-MoO 2 /NF, exposing abundant oxygen vacancies and the low-oxidation-state of Mo sites during the rapid Joule heating process. As tested, the catalyst exhibited superior activity with ultralow overpotentials (HER: 17 mV@10 mA cm -2 ; oxygen evolution reaction (OER): 310 mV@50 mA cm -2 ) and high OER selectivity in alkaline seawater splitting. Meanwhile, this catalyst was equipped in a home-made anion exchange membrane (AEM) seawater electrolyzer, which achieved a low energy consumption (5.5 kW h m -3 ). More importantly, Fe-MoO 2 /NF also coupled very well with a solar-driven electrolytic system and turned out a solar-to-hydrogen (STH) efficiency of 13.5%. Theoretical results also demonstrated that Fe incorporated and abundant oxygen vacancies in MoO 2 can distort the distance of the Mo-O bonds and regulate the electronic structure, thus optimizing the binding energy of H*/OOH* adsorption. This method can be extended to other heterogeneous spin states in MoO 2 -based catalysts ( e.g. Ni-MoO 2 /NF, Co-MoO 2 /NF) for seawater splitting, and provide a simple, efficient and universal strategy to prepare highly-efficient MoO 2 -based electrocatalysts.

Suffering from the formation of metal-ion dendrites and low storage capacity, MXene materials exhibit unsatisfactory performance in Li and Na storage. In this study, we demonstrate that the MXene V 3 C 2 Cl 2 structure can induce uniform Li and Na deposition. This is achieved through coherent heterogeneous interface reconstruction and regulated ion tiling by halogen surface termination. The high lattice matching (91% and 99%) between MXenes and Li/Na, along with positive Cl terminal regulation, guides Li/Na ions to nucleate uniformly on the V 3 C 2 Cl 2 MXene matrix and grow in a planar manner. Cl termination proves effective in regulating Li/Na ions due to its moderate adsorption and diffusion coefficients. Furthermore, upon adsorption onto the Cl-terminated V 3 C 2 Cl 2 monolayer, Li 4 and Na 4 clusters undergo dissociation, favoring uniform adsorption over cluster adsorption. V 3 C 2 Cl 2 MXenes exhibit impressive Li/Na storage capacities of 434.07 mA h g -1 for Li and 217.03 mA h g -1 for Na, surpassing the Li storage capacity of Ti 3 C 2 Cl 2 by three-fold and the Na storage capacity of V 2 C by 1.4 times. This study highlights the regulatory role of Cl surface terminals in dendrite formation and Li/Na ion deposition, with potential applications to other metal-ion storage electrodes.

Semiconducting polymer dots and hemin-functionalized DNA nanoflowers with excellent peroxidase-like activity and high fluorescent brightness are prepared for fluorescent/colorimetric dual-mode sensing of dopamine and glutathione as low as nM and μM, respectively. This biosensor is readily applied to the analysis of complicated biological samples with high selectivity and accuracy, which opens up promising prospects in clinical applications.

The design of multifunctional nanomedicine through the combination of multimodal treatments to achieve the optimal antitumor effect is essential for cancer therapy. Herein, we design and develop a multifunctional theranostic nanoplatform using an iron ion-doxorubicin (DOX) nanoscale coordination polymer (Fe/DOX NCP) as a shell coating on the surface of polyvinyl pyrrolidone (PVP) stabilized copper-diethyldithiocarbamate nanoparticles (Cu(DDC) 2 NPs) for combined tumor chemo-/photothermal/chemodynamic therapy. The obtained Cu(DDC) 2 @Fe/DOX NPs display pH/laser dual-responsive degradation behavior and also exhibit favorable photothermal performance. Under 808 nm laser irradiation, Cu(DDC) 2 @Fe/DOX NPs can convert light into heat, which not only kills tumor cells via hyperthermia in photothermal therapy (PTT), but also accelerates the degradation of Fe/DOX NCPs to release Fe 3+ and DOX. The liberated Fe 3+ can be used to catalyze hydrogen peroxide via the Fenton reaction to produce highly toxic hydroxyl radicals (˙OH) in chemodynamic therapy (CDT). The released DOX and the exposed Cu(DDC) 2 can cause significant cell death in combined chemotherapy via a superimposed effect. In vitro and in vivo results prove that Cu(DDC) 2 @Fe/DOX NPs with laser irradiation present remarkable anticancer performances in hyperthermia-enhanced chemo-/CDT. Therefore, this study provides a new strategy for highly efficient synergistic cancer therapy.

Ever-growing demands for zinc-air batteries (ZABs) call for the development of advanced electrocatalysts. Single-atom catalysts (SACs), particularly those for isolating non-noble metals (NBMs), are attracting great interest due to their merits of low cost, high atom utilization efficiency, structural tunability, and extraordinary activity. Rational design of advanced NBM SACs relies heavily on an in-depth understanding of reaction mechanisms. To gain a better understanding of the reaction mechanisms of oxygen electrocatalysis in ZABs and guide the design and optimization of more efficient NBM SACs, we herein organize a comprehensive review by summarizing the fundamental concepts in the field of ZABs and the recent advances in the reported NBM SACs. Moreover, the selection of NBM elements and supports of SACs and some effective strategies for enhancing the electrochemical performance of ZABs are illustrated in detail. Finally, the challenges and future direction in this field of ZABs are also discussed.

In this work, a portable electrochemical glucose sensor was studied based on a laser-induced graphene (LIG) composite electrode. A flexible graphene electrode was prepared using LIG technology. Poly(3,4-ethylene dioxythiophene) (PEDOT) and gold nanoparticles (Au NPs) were deposited on the electrode surface by potentiostatic deposition to obtain a composite electrode with good conductivity and stability. Glucose oxidase (GOx) was then immobilized using glutaraldehyde (GA) to create an LIG/PEDOT/Au/GOx micro-sensing interface. The concentration of glucose solution is directly related to the current value by chronoamperometry. Results show that the sensor based on the LIG/PEDOT/Au/GOx flexible electrode can detect glucose solutions within a concentration range of 0.5 × 10 -5 to 2.5 × 10 -3 mol L -1 . The modified LIG electrode provides the resulting glucose sensor with an excellent sensitivity of 341.67 μA mM -1 cm -2 and an ultra-low limit of detection (S/N = 3) of 0.2 × 10 -5 mol L -1 . The prepared sensor exhibits high sensitivity, stability, and selectivity, making it suitable for analyzing biological fluid samples. The composite electrode is user-friendly, and can be built into a portable biosensor device through smartphone detection. Thus, the developed sensor has the potential to be applied in point-of-care platforms such as environmental monitoring, public health, and food safety., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We report a straightforward H/D exchange method for the synthesis of α-deuterated primary amines from a diverse set of primary amines with high levels of deuteration and chemo- and site selectivity and preparative utility. This cost-effective strategy enables the direct conversion of primary amines to α-deuterated counterparts using D 2 O as the deuterium source under mild reaction conditions without requiring additional functionality manipulation and with minimal byproduct production.

Designing an effective photoactive heterojunction having dual benefits towards photoenergy conversion and pollutant adsorption is regarded as an affordable, green method for eliminating tetracycline (TC) from wastewater. In this regard, a series of BiOBr@NU-1000 (BNU- X , X = 1, 2 and 3) heterojunction photocatalysts are constructed. BNU- X preserves the original skeleton structure of the parent NU-1000, and its high porosity and specific surface area enable superior TC adsorption. At the same time, BNU- X is an effective Z-scheme photocatalyst that improves light trapping, promotes photoelectron-hole separation, and shows excellent photocatalytic degradation efficiency towards TC with the value of the photodegradation kinetic rate constant k being 2.2 and 24.8 times those of NU-1000 and BiOBr, respectively. The significant increase in the photocatalytic activity is ascribed to the construction of an efficient Z-scheme photocatalyst, which promotes the formation of superoxide radicals (˙O 2 - ) and singlet oxygen ( 1 O 2 ) as the main oxidative species in the oxidation system. This research has the advantage of possibilities for the development of porous Z-scheme photocatalysts based on photoactive MOF materials and inorganic semiconductors for the self-purification and photodegradation of organic contaminants.

In this work, NaH 2 PO 2 , Na 2 S 2 O 3 and CdCl 2 were used to synthesize P-doped CdS samples for the photocatalytic decomposition of formic acid to CO reaction. The CO production rates and selectivity of P-doped CdS are as high as 24.5 mmol g -1 h -1 and 92.4%, in which the rate is 7 times higher than that of the pure CdS. Multiple characterizations show that the P-doping increases the specific surface area, widens the band gap and shifts the energy band position of CdS, resulting in enhanced photocatalytic activity.

The commercialization of lithium-sulfur batteries is facing great challenges, such as the "shuttle effect" and the poor conductivity of sulfur and Li 2 S 2 /Li 2 S, so it is extremely important to design new separator-modified materials with fast charge transfer capability and effective immobilization of polysulfides (LiPSs) to facilitate their conversion to address these challenges. In this paper, we propose a simple way to synthesize NiCo 2 O 4 nanospheres containing oxygen vacancies (O V -NiCo 2 O 4 NSs) and thus modify the separator. The synthesized O V -NiCo 2 O 4 NSs accelerated the conversion of LiPSs through strong chemical interactions. In addition, the introduction of oxygen vacancies provided more active sites for LiPSs, which improved the electron conduction rate and accelerated the ion transport. Based on the above advantages, the battery with an O V -NiCo 2 O 4 modified separator showed excellent electrochemical performance (the initial capacity of the battery was 801 mA h g -1 at 0.5 C, the specific capacity of discharge was maintained at 695 mA h g -1 after 500 cycles, and the capacity retention rate was as high as 87%).

Adjusting the micro-environment of highly dispersive metals on carbon supports has been proved to be effective for achieving enhanced electrocatalysis performance. Herein, we delicately design a phosphorus-doped binary NiFe-nitrogen-carbon material (denoted as P-NiFe-NC), taking advantage of the coupling reaction between phenylphosphonamide (P dopant) and formamide (the carbon and nitrogen sources). The XPS N 1s fine scan reveals the strong interplay of N and P by the positively shifted binding energy of pyridinic N species after P incorporation, and the chemical state of Fe species is influenced accordingly. In addition, the P doping can enlarge the specific surface area and increase the meso/macroporosity of NiFe-NC, thus contributing to the enhancement of mass transfer inside the pores. The P-NiFe-NC sample exhibits favorable bifunctional oxygen electrocatalysis performance, rendering an ORR half-wave potential of 0.85 V and an OER potential of 1.69 V@10.0 mA cm -2 , superior to those of P-free NiFe-NC. Assembled into Zn-air batteries, P-NiFe-NC delivers a high specific power of 161.36 mW cm -2 and stable charge/discharge for over 100 h (corresponding to 300 cycles).

The two-dimensional (2D) metallic phase of MoS 2 , 1T-MoS 2 , has extraordinary electrical conductivity in contrast to the common 2D semiconducting phase, 2H-MoS 2 . However, the thermodynamic instabilities of 1T-MoS 2 hinder its application. In this work, we investigate the possibilities of stabilizing 1T-MoS 2 through heterostructure design using first-principles calculations. We found that MXene-based heterostructures could hamper phase transitions from 1T-MoS 2 to 2H-MoS 2 enabled by a larger phase transition kinetic energy barrier. Based on this finding, we propose a general and effective strategy for stabilizing 1T-MoS 2 , that is, building heterostructures using 1T-MoS 2 and oxygen-functionalized MXenes. Besides, we have also observed that due to the occurrence of electron transfer in the heterostructure, 1T-MoS 2 in the heterostructure exhibits improved hydrogen adsorption free energy and more active sites compared to the monolayer 1T-MoS 2 . These findings provide guidance for promoting and developing 1T-MoS 2 for practical applications. In addition, the proposed heterostructure design strategy could inspire the study of phase transition behaviors and electrochemical properties of materials using interfaces.

The intercalation of H into Pd-based nanocatalysts plays a crucial role in optimizing the catalytic performance by tailoring the structural and electronic properties. We herein present a comprehensive review about the recent progress of interstitial hydrogen atom modified Pd-based nanocatalysts for various energy-related electrocatalytic reactions. Before systematically manifesting the great potential of Pd-based hydrides for electrocatalytic applications, we have briefly illustrated the synthesis strategies and corresponding mechanisms for the Pd-based hydrides. This is followed by a comprehensive discussion about the fundamentals and functions of H intercalation in tailoring their physicochemical and electrochemical properties. Subsequently, we focus on the widespread application of Pd-based hydrides for electrocatalytic reactions, with the emphasis on the role of H intercalation played in determining electrocatalytic performance. Finally, the future direction and perspectives regarding the development of more efficient Pd-based hydrides are also manifested.

CuCo 2 S 4 as a spinel-structured transition metal sulfide is a highly effective HER catalyst due to its excellent endurance, low overpotential, and low Tafel slope. In this work, the CuCo 2 S 4 /Ni foam (NF) catalysts with various morphologies have been successfully synthesized by controlling the ratio of urea and ammonium fluoride (NH 4 F) based on the hydrothermal method. Urea and NH 4 F ratio exhibit a great influence on the microstructure and the HER catalytic performance of CuCo 2 S 4 /NF catalysts is discussed in detail., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Water pollution causes the propagation of pathogenic microorganisms, which poses a serious threat to human life. Escherichia coli O157:H7, as a representative organism that can directly exhibit molecular response to stress, was selected as the indicator bacteria for the study. Tandem mass tag (TMT) quantitative proteomics and non-targeted metabolomics were used to study the response of Escherichia coli O157:H7 to Aronia melanocarpa anthocyanin (AMA) treatment. The results showed that 628 proteins and 1338 metabolites changed significantly after treatment with AMAs. According to bioinformatics analysis, integrated proteomics and metabolomics analysis differentially expressed proteins (DEPs) and metabolites participate in pyruvate metabolism, glycolysis/gluconeogenesis, alanine, aspartate and glutamate metabolism and the pentose phosphate pathway. This study preliminarily proposed the inhibition mechanism of AMAs on Escherichia coli O157:H7 from the perspective of multi-omics, providing a theoretical basis for the application of natural preservatives in fresh cut vegetables.

The structure and electronic properties of two-dimensional vertical van der Waals PtSe 2 /Hf 2 CO 2 heterostructure have been investigated based on first-principles calculations. The results show that the PtSe 2 and Hf 2 CO 2 monolayers form a type-I heterostructure with both the conduction band minimum (CBM) and valence band maximum (VBM) located at the Hf 2 CO 2 layer. The electronic properties of PtSe 2 /Hf 2 CO 2 heterostructure can be effectively adjusted by applying external electric field or biaxial strain. The transition in band alignment from type-I to type-II can be manipulated by controlling the strength and direction of the electric field. Additionally, the transition from type-I to type-II have also taken place under the strains, and the band gap of the PtSe 2 /Hf 2 CO 2 heterostructure decreases with increasing the compressive or tensible strain. Under a strong strain of -8%, the PtSe 2 /Hf 2 CO 2 heterostructure can transform from semiconductor to metal. These findings provide a promising method to tune the electronic properties of PtSe 2 /Hf 2 CO 2 heterostructure and design a new vdW heterostructure in the applications for electronic and optoelectronic devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Anaplastic thyroid cancer (ATC) is the most malignant and aggressive of all classifications of thyroid cancer. ATC normally has poor prognosis after classic treatments such as surgery, endocrine therapy, radiotherapy and chemotherapy. Herein, a novel nanocomposite (named as UCNP@PDA@LEN) has been synthesized for chemo-photothermal therapy of ATC, which is based on a NaErF 4 :Tm 3+ @NaYbF 4 @NaYF 4 :Nd 3+ upconverting nanoparticle (UCNP) as the core, a near-infrared light (NIR)-absorbing polydopamine (PDA) as the shell, and lenvatinib (LEN) as a chemotherapeutic drug. The as-prepared multifunctional UCNP@PDA@LEN exhibits excellent photothermal conversion capability ( η = 30.7%), good photothermal stability and reasonable biocompatibility. Owing to the high UCL emission and good tumor accumulation ability, the UCL imaging of mouse-bearing ATC ( i.e. , C643 tumor) has been achieved by UCNP@PDA@LEN. Under 808 nm NIR laser irradiation, the UCNP@PDA@LEN shows a synergistic interaction between photothermal therapy (PTT) and chemotherapy (CT), resulting in strongly suppressed mouse-bearing C643 tumor. The results provide an explicit approach for developing theranostics with high anti-ATC efficiency., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Designing novel two-dimensional (2D) ferroelectric materials by symmetry breaking and studying their mechanisms play important roles in the discovery of new ferroelectric photocatalysts and nanoelectronics. In this study, we have systematically investigated a series of novel ferroelectric 2D HfSnX 3 (X = S, Se and Te) monolayers through first-principles calculations. We found that each HfSnX 3 monolayer contains a stable ferroelectric phase (FP) and a paraelectric phase (PP). The large polarization (up to 1.64 μC cm -2 ) in the FP can significantly bend the oxidation reduction potential of water, making HfSnX 3 monolayers become excellent ferroelectric photocatalysts. Specifically, by designing a Janus structure to break the symmetry of the PP, we have excitingly obtained a stable Hf 2 GeSnSe 6 (referred to as HGSS) monolayer with triple polarized states. HGSS not only possesses great visible light absorption properties (about 3 × 10 5 cm -1 ) as photocatalysts but also successfully solves the dead layer problem previously reported in practical applications. In addition, by constructing a heterostructure with graphene, HGSS has great application in the design of controllable ultrathin p-n junctions. Overall, our study not only predicts a series of potential ferroelectric photocatalytic materials, but also provides valuable insights for designing tunable polarized materials and nanoelectronics.

NHC-mediated deoxygenation of alcohols under photocatalytic conditions is described. The process provides various alkyl radicals, which can react with 1-bromoalkyne via Csp 3 -Csp coupling to afford internal alkynes in moderate to good yields. The method offers a new and convenient approach to synthesize internal alkynes.

The removal of methylene blue (MB) in water is a challenging task due to its toxicity, carcinogenicity and resistance to biodegradation. Accordingly, a novel composite catalyst (BC@LF) was prepared by loading lanthanum ferrite (LaFeO 3 ) on biomass carbon (BC) to activate bisulfite (BS) for methylene MB removal in this study. Characterization via scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) indicated that LaFeO 3 was successfully loaded on BC. X-ray photoelectron spectroscopy (XPS) analysis suggested that [triple bond, length as m-dash]Fe(iii) was the main active site for BS activation. It was found that 99.4% MB was removed within 60 min in BC@LF/BS system. Sulfate radical (SO 4 ˙ - ) and hydroxyl radicals (HO˙) were proved to be responsible for MB removal in the BC@LF/BS system and SO 5 ˙ - might also be involved in MB removal. The degradation efficiency of MB in the BC@LF/BS system decreased with increasing pH, while the adsorption efficiency of BC@LF for MB improved with increasing pH. Additionally, BC@LF exhibited good reusability for BS activation in successive uses. The BC@LF/BS system exhibited favorable removal effect for various organic compounds, indicating that it has good applicability in the treatment of organic wastewater., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Considering the molar mass between entanglements to be an intrinsic property of ultra-high molecular weight polyethylene (UHMWPE), the number of entanglements per chain increases with increasing molar mass, correspondingly making the UHMWPE intractable. Herein, we dispersed TiO 2 nanoparticles with different characteristics into UHMWPE solutions to disentangle the molecular chains. Compared with the UHMWPE pure solution, the viscosity of the mixture solution declines by 91.22%, and the critical overlap concentration increases from 1 wt% to 1.4 wt%. A rapid precipitation method was utilized to obtain UHMWPE and UHMWPE/TiO 2 composites from the solutions. The melting index of UHMWPE/TiO 2 is 68.85 mg, which is in sharp contrast to that of UHMWPE which is 0 mg. We characterized the microstructures of UHMWPE/TiO 2 nanocomposites using TEM, SAXS, DMA, and DSC. Accordingly, this significant improvement in processability contributed to the reduction of entanglements and a schematic model was proposed to explain the mechanism by which nanoparticles disentangle molecular chains. Simultaneously, the composite demonstrated better mechanical properties than UHMWPE. In summary, we provide a strategy to promote the processability of UHMWPE without sacrificing its outstanding mechanical properties.

Ice nucleation plays a vital function in various fields. In this study, we prepared hydrogel surfaces with different cross-linkages by pH-modulating the coordination pattern of Fe 3+ and catechol. We found that the ice nucleation temperature decreases with increasing cross-linkages. Further analysis shows that the hydrogel surfaces with different cross-linking degrees could achieve the regulation of ice nucleation by modulating the interfacial water. Our study elucidates the mechanism of ice nucleation regulated by interfacial water in soft matter and proposes a new method for preparing ice nucleation-regulated material.

A new complex rare earth borate K 7 PbLu 2 B 15 O 30 was prepared by the spontaneous crystallization method. K 7 PbLu 2 B 15 O 30 is crystallized in the chiral trigonal space group R 32 with cell parameters a = b = 13.0893(3) Å, c = 15.2379(6) Å, α = β = 90°, γ = 120°, and Z = 3. The basic structure of the crystal can be seen as composed of B 5 O 10 groups and LuO 6 polyhedra sharing oxygen atoms, while K + and Pb 2+ fill the space to balance the charge. The UV transmission cut-off edge of K 7 PbLu 2 B 15 O 30 was less than 300 nm, and the powder SHG response was roughly 1.1 times that of KDP. Furthermore, a first-principles analysis was performed to see more about the relationship between the crystal structure and optical characteristics.

Arsenate (As(V)) is a fatal poison and is widely distributed in the environment. The quick and accurate determination of As(V) is of great importance. Herein, we developed a novel competitive coordination strategy for the quantification of ultratrace As(V) using online internal extractive electrospray ionization mass spectrometry (iEESI-MS). Our strategy demonstrates great success for direct ultratrace As(V) detection in broad types of samples, from solids to liquids, such as food, water and biological samples.

Janus particles have been considered suitable for biomedicine owing to their asymmetric structure and unique properties. Although Janus particles have been applied in biosensing for dual-mode sensing, there are almost no reports for the detection of multiple indicators. In fact, many patients require different diagnoses, such as the examination of hepatogenic diseases in diabetics. Here, a Janus particle based on SiO 2 was synthesized using a Pickering emulsion method. A novel strategy for detecting glucose and alpha-fetoprotein (AFP) based on different principles using this Janus particle was then constructed as a detection platform. Composed of adjustable dendritic silica loaded with gold nanoclusters (Au NCs) and glucose oxidase (GOx) and spherical SiO 2 coupled with AFP antibody, this Janus fluorescent probe achieved the double detection of glucose and AFP. With the protection of dendritic silica, the enzyme temperature stability was enhanced. Moreover, the low limit of detection for glucose (0.5 μM in PBS and 2.5 μM in serum) and AFP (0.5 ng mL -1 ) illustrated the feasibility of the application of the Janus material in integrated detection. This work not only supported the use of a Janus fluorescent probe as a detection platform toward glucose and AFP but also showed the potential of Janus particles in integrated detection in the future.

A range of cinchona-alkaloid-derived NN ligands bearing N-H were employed for the asymmetric hydrogenation of ketones. By substituting N-H of the ligands, we demonstrated that the N-H moiety was essential for asymmetric hydrogenation and that without the N-H moiety asymmetric hydrogenation could not proceed, based on which a proposed mechanism is discussed. The effectiveness of the optimal ligand was evaluated on various aromatic and α,β-unsaturated ketones, producing the corresponding alcohols with up to 98.8% ee and good yields.