In situ Gel Electrolytes for the Interfacial Regulation of Lithium Metal Batteries.

With the popularity and development of electronic devices, the demand for lithium batteries is increasing, which also puts high demands on the energy density, cycle life and safety of lithium batteries. Gel electrolytes achieve both of these requirements by curing the electrolytes to reduce the interfacial side reactions of lithium metal batteries. The ionic conductivity of the gel electrolytes prepared by in situ curing reach 8.0×10-4  S cm-1 , and the ionic mobility number is 0.53. Meanwhile, the gel electrolytes maintain a stable electrochemical window of 1.0-5.0 V. Benefited with the interfacial regulation of PEGDA gel electrolytes, the gel lithium metal batteries show better cycling stability, and achieved 97 % capacity retention after 200 cycles (0.2 C) with a lower increasing rate of impedance.

Enhanced bioremediation performance of diesel-contaminated soil by immobilized composite fungi on rice husk biochar.

In response to the low removal capacity and poor tolerance of fungi to diesel-contaminated soil, a novel immobilization system using biochar to enhance composite fungi was proposed. Rice husk biochar (RHB) and sodium alginate (SA) were used as immobilization matrices for composite fungi, and the adsorption system (CFI-RHB) and the encapsulation system (CFI-RHB/SA) were obtained. CFI-RHB/SA exhibited the highest diesel removal efficiency (64.10%) in high diesel-contaminated soil over a 60-day remediation period compared to the free composite fungi (42.70%) and CFI-RHB (49.13%). SEM demonstrated that the composite fungi were confirmed to be well attached to the matrix in both CFI-RHB and CFI-RHB/SA. FTIR analysis revealed the appearance of new vibration peaks in diesel-contaminated soil remediated by immobilized microorganisms, demonstrating changes in the molecular structure of diesel before and after degradation. Furthermore, CFI-RHB/SA maintains a stable removal efficiency (>60%) in higher concentrations of diesel-contaminated soil. High-throughput sequencing results indicated that Fusarium and Penicillium played a key role in the removal of diesel contaminants. Meanwhile, both dominant genera were negatively correlated with diesel concentration. The addition of exogenous fungi stimulated the enrichment of functional fungi. The insights gained from experiment and theory help to provide a new understanding of immobilization techniques of composite fungi and the evolution of fungal community structure.

Studies on stabilization effect of calcium dihydrogen phosphate (Ca(H2PO4)2) on Lead(Pb)-contaminated Soil.

This study investigated the effect of Ca(H2PO4)2 on pH, leaching toxicity and speciations of soil before and after leaching on it. Different amounts of Ca(H2PO4)2 were added to Pb-contaminated soil and stabilized for 30 days. The changes of pH and leaching toxicity of Pb-contaminated soil were tracked during that period. The content of Pb in soil before and after leaching was also determined after 30 days of stabilization. Results showed that the pH of the Pb-contaminated soil didn't change much with the addition of-Ca(H2PO4)2. When the amount of Ca(H2PO4)2 reached to 3 wt%, the leaching toxicity met the standard limiting level of groundwater class III of China. The change of leaching toxicity was found to be mainly affected by the water-soluble fraction and mild acid-soluble fraction of lead. The speciation experiments revealed that the changes on reducible, oxidizable, and residual fractions are significant, while there are only minor changes on the water-soluble and mild acid-soluble fractions. X-ray diffractometry (XRD) analysis showed that Pb9(PO4)6 and Pb2P2O7 substances were generated in the stabilized soil. The stabilization mechanism of Ca(H2PO4)2 was mainly attributed to the formation of insoluble Pb phosphate precipitates through interactions between the heavy metal Pb and the Ca(H2PO4)2. In such a way the active species of Pb in the soil can be successfully stabilized. Novelty statementAt present, the leaching toxicity is currently used for the evaluation of stabilization effect of heavy metal contaminated soil. The speciation distribution of stabilized contaminated soil before and after leaching has rarely been studied, and the research on stabilizing contaminated soil after leaching is less.Therefore, this paper mainly studies the stabilization effect through the speciation changes of contaminated soil before and after leaching, providing a new idea and method for the evaluation of the stabilization effect of contaminated soil remediation.Ca(H2PO4)2 has no significance in pH of contaminated soil: 5.05＜pH＜5.5.The content of the water-soluble fraction and the mild acid-soluble fraction of Pb were availably reduced by Ca(H2PO4)2.The content of the water-soluble fraction and the mild acid-soluble fraction of Pb has no marked change before and after leaching.The stabilization mechanism of Ca(H2PO4)2 is through interaction between the Pb in the soil and phosphate to form insoluble substances of lead phosphate.Ca(H2PO4)2 has a good effect on the stabilization of lead-contaminated soil.

Sub-Nanometer Confined Ions and Solvent Molecules Intercalation Capacitance in Microslits of 2D Materials.

The ion intercalation behavior in 2D materials is widely applied in energy storage, electrocatalysis, and desalination. However, the detailed effect of ions on the performance, combining the influence of interlayer force and the change of solvent shell, is far less well understood. Here the solvated alkali metal ions with different sizes are intercalated into the lattice of 2D materials with different spacings (Ti3 C2 Tx , δ-MnO2 , and reduced graphene oxide) to construct the intercalation model related with sub-nanometer confined ions and solvent molecules to further understand the intercalation capacitance. Based on electrochemical methods and density functional theory calculation, the ions lose the electrostatic shielding solvent shell or shorten the distance between the layers, resulting in a significant increase in capacitance. It is found that the intercalation capacitance arises from the diffusion of solvated ions and is controlled by quantum and electrochemical capacitance for desolvated ions. This effect of solvation structure on performance can be applied in a variety of electrochemical interface studies and provides a new research view for energy storage mechanisms.

Antitumor immunity triggered by photothermal therapy and photodynamic therapy of a 2D MoS2 nanosheet-incorporated injectable polypeptide-engineered hydrogel combinated with chemotherapy for 4T1 breast tumor therapy.

A multifunctional PC10A/DOX/MoS2 hydrogel was designed and prepared for chemotherapy/photothermal therapy/photodynamic therapy of 4T1 tumor, and the immune responses triggered by photothermal and photodynamic effect of MoS2 nanosheet in the hydrogel were also studied. Positively charged DOX and negatively charged PC10A were loaded on the surface of MoS2 nanosheet through layer-by-layer method to prepare hybrid PC10A/DOX/MoS2 nanoparticles. PC10A/DOX/MoS2 nanoparticles were dispersed in PC10A hydrogel to prepare PC10A/DOX/MoS2 hydrogel. 2D MoS2 nanosheet in the hydrogel was simultaneously utilized as photothermal agent and photodynamic agent for the generation of hyperthermia and reactive oxygen species, respectively. This PC10A/DOX/MoS2 hydrogel was injectable and possessed excellent biocompatibility. The results of in vivo tumor-bearing mice experiments showed that a remarkably enhance tumor inhibition was observed by the combination of chemo-photothermal-photodynamic therapy compared with photothermal therapy, photodynamic therapy, or chemotherapy alone. In addition, the results of in vivo therapy exhibited that the PC10A/DOX/MoS2 hydrogel with laser irradiation could activate antitumor immune effects to suppress the growth of primary 4T1 breast tumors and distal lung metastatic nodules. Therefore, these results demonstrated that the PC10A/DOX/MoS2 hydrogel was promising to be utilized in antitumor immunity therapy triggered by photothermal therapy and photodynamic therapy for malignant tumor.

Study on the process of harmless treatment of residual electrolyte in battery disassembly.

Residual electrolyte is the main pollution source in the lithium ion battery disassembly process. A practical detoxified approach is studied using the lithium hexafluorophosphate in the decommissioned power battery with dimethyl carbonate as a solvent. The pH measurement, Fourier transform infrared spectroscopy, micromorphology and phase structure characterization techniques showed that the process in this study is capable of removing lithium hexafluorophosphate from decommissioned power batteries, while controlling the proper ratio of NaOH can also completely precipitate F- into CaF2 crystal and allows recycling of the organic solvents. This process scheme of residual electrolyte treatment effectively reduces environmental pollution during the decommissioned power batteries recycling process, and has the benefit of resource reuse for valuable elements.

Polypyrrole Encapsulated Nickel Nanorods for Conductivity Improvement by Magnetic Alignment.

Polypyrrole encapsulated nickel nanorods (PPy@Ni) have been prepared by electro-polymerization using Ni nanorods as template. PPy@Ni were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectrometer, Fourier transform infrared (FTIR) spectra and vibrating sample magnetometry (VSM). The maximum saturation magnetization of PPy@Ni was up to 44.6 emu g-1. Further, PPy@Ni was used as the additive for the conductivity improvement in polymer matrix. Experimental results showed that the electric conductivity reached 1.8×10-3 S m-1 when 5% PPy@Ni was added in the poly(urethane acrylate) matrix by applying a magnetic field. Further tests showed that when the additive concentration increased from 0.1% to 5%, the correspondence saturation magnetization increased from 15.1 emug-1 to 31.3 emug-1. This work provides new light on controllable fabrication of conducting polymer by adding magnetic alignment conductive additives.

High quantum yield and well-dispersed quantum dots luminescent composite through sodium carboxymethyl starch.

It is a challenging task to prepare well-dispersed and highly luminescent quantum dots (QDs) powder and a new strategy is reported in this article. Sodium carboxymethyl starch (CMS-Na) was employed in this work to prepare the QDs-starch composite. Ultraviolet (UV) light shows that the blank starches had no fluorescence, while the QDs-starches were highly luminescent. Scanning electron microscopy (SEM) observation shows that the QDs-starch composite has the typical particle morphology with the diameter around 200 nm. Energy dispersive X-ray spectroscopy (EDX) results show that there are intensive tellurium (Te) and cadmium (Cd) element signals. Combined fluorescent lifetime and steady-state spectrometer show that the QDs-starch quantum yields (QYs) increase when the QDs loading increases from 1 × 10-6 mol/g to 2 × 10-6 mol/g, but when the loadings further increase, the QYs decrease slightly. For the red colour (λem  = 660 nm) QDs, the QYs can reach to as high as 28.2%, and for the other colour QDs they can also have the QYs above 22%. Time-resolved photobleaching experiments show that the fluorescent QDs-starch composite has a half-decay time of 40.23 s. These results indicate that the CMS-Na is a promising QDs dispersant to obtain high QY QD composites.

A Novel Fluorescent Nanoparticle for Sensitive Detection of Cry1Ab Protein In Vitro and In Vivo.

Here, we report the synthesis and characterization of CoFe2O4 doping Ag2S dendrimer-modified nanoparticles (CoFe2O4-Ag2S DMNs) in Cry1Ab protein detection and imaging. The near-infrared Ag2S quantum dots were first prepared by using the thermal decomposition method, followed by modification of the water-soluble quantum dots using the method of solvent evaporation and ligand exchange, and finally the fluorescent magnetic bifunctional nanoparticles were obtained by binding with CoFe2O4. As-prepared CoFe2O4-Ag2S DMNs were characterized by fluorescence (FL) spectroscopy and transmission electron microscopy (TEM). Results showed that Ag2S DMNs could sensitively detect Cry1Ab both in vitro and in vivo. In vitro, the enhanced FL intensity as a function of the concentration is notably consistent with the Langmuir binding isotherm equation in the range of 0-200 ng/mL of Cry1Ab proteins. The detection limit of this method was found to be 0.2 ng/mL. Meanwhile, the fluorescence wavelength was extended to the second near-infrared range (NIR-II, 1.0~1.4 µm), which enables in vivo imaging. This study highlights the importance of NIR QDs doping magnetic materials as a new method to trace Bacillus thuringiensis (Bt) in insects and their potential applications in in vivo NIR tissue imaging.

A multifunctional targeting probe with dual-mode imaging and photothermal therapy used in vivo.

BACKGROUND: Ag2S has the characteristics of conventional quantum dot such as broad excitation spectrum, narrow emission spectrum, long fluorescence lifetime, strong anti-bleaching ability, and other optical properties. Moreover, since its fluorescence emission is located in the NIR-II region, has stronger penetrating ability for tissue. Ag2S quantum dot has strong absorption during the visible and NIR regions, it has good photothermal and photoacoustic response under certain wavelength excitation. RESULTS: 200 nm aqueous probe Ag2S@DSPE-PEG2000-FA (Ag2S@DP-FA) with good dispersibility and stability was prepared by coating hydrophobic Ag2S with the mixture of folic acid (FA) modified DSPE-PEG2000 (DP) and other polymers, it was found the probe had good fluorescent, photoacoustic and photothermal responses, and a low cell cytotoxicity at 50 µg/mL Ag concentration. Blood biochemical analysis, liver enzyme and tissue histopathological test showed that no significant influence was observed on blood and organs within 15 days after injection of the probe. In vivo and in vitro fluorescence and photoacoustic imaging of the probe further demonstrated that the Ag2S@DP-FA probe had good active targeting ability for tumor. In vivo and in vitro photothermal therapy experiments confirmed that the probe also had good ability of killing tumor by photothermal. CONCLUSIONS: Ag2S@DP-FA was a safe, integrated diagnosis and treatment probe with multi-mode imaging, photothermal therapy and active targeting ability, which had a great application prospect in the early diagnosis and treatment of tumor.

In-Situ Template Formation Strategy for the Preparation of Nitrogen Doped Carbon Nanocage with Graphitic Shell as Electrode Material for Supercapacitor.

Nitrogen doped carbon nanocage with graphitic shell (NGCS) was fabricated through in-situ solid reaction between calcium acetate and dicyandiamide in an inert atmosphere followed by acid etching. The role played by the calcium acetate (Ca(Ac)2) and dicyandiamide (DCD) during the synthesis process is one-stone-two-birds. Calcium acetate plays multiple functions: template agent, graphitization catalyst, and carbon source. Dicyandiamide can be considered as the nitrogen sources and the chemical reaction agent that can be reacted with calcium acetate to form it into CaCN2. The NGCS obtained at 800 °C has a specific surface area of 420 m2/g and nitrogen content of 8.87 at%. The excellent electrochemical performance can be attributed to the combination effects of porous structure, nitrogen doping and graphitized nanocage shell of NGCS electrode. The hollow structure serves as the reservoir for fast electrolyte ion supplement. Nitrogen groups not only improve the wettability of interfaces between carbon surface and electrolyte, but also generate extra pseudocapacitance through redox reaction. The graphitic carbon nanocage shell can enhance the conductivity and facilitates the fast charge transfer. At a current density of 0.5 A/g, the specific capacitance of the NGCS-800 electrode is 215 F/g. Furthermore, the NGCS-800 electrode exhibits excellent rate capability (80% capacitance retention at 10 A/g) and outstanding cycling stability (96.89% capacitance retention after 5000 cycles). These intriguing results demonstrate that nitrogen doped carbon with graphitic shell will be highly promising as electrode materials for supercapacitors and other energy storage and conversation applications.

Quaternary Ammonium Polyamidoamine Dendrimer Modified Quantum Dots as Fluorescent Probes for p-Fluorophenoxyacetic Acid Detection in Aqueous Solution.

The wide use of pesticide p-fluorophenoxyacetic acid has caused the serious environmental contaminant. A novel fluorescent probe for sensitive detection of p-fluorophenoxyacetic acid in aqueous solutions based on 3.0G quaternary ammonium polyamidoamine (PAMAM) dendrimer modified quantum dots (QDs) (PAMAM@QDs) was reported. Through the solvent-evaporation method, quaternary ammonium PAMAM was employed to modify the QDs. Poloxamer 188 was used to improve the solubility and stability. The resultant PAMAM@QDs dispersed well in water. Fluorescence (FL) spectroscopic study showed that the FL intensity of the PAMAM@QDs was enhanced in the presence of p-fluorophenoxyacetic acid. Under optimal conditions, the enhanced FL intensity as a function of concentration matched very well in the range of 1 ~ 200 µg/mL of p-fluorophenoxyacetic acid, while the lower limits of detection were found to be 0.16 µg/mL. These results show that PAMAM@QDs is a promising luminescent probe for the detection of pesticides.

Graphite oxide-dispersed CdTe quantum dots nanocomposite for flexible display luminescent membranes.

A quantum dot (QD) dispersant material was prepared using graphite oxide (GO). Luminescent films were prepared using polyvinyl alcohol as the polymer matrix. First, water-soluble CdTe QDs were prepared by wet chemistry and GO was synthesized using a modified Hummers method. X-Ray diffraction tests showed that the GO reflection peak [001] was 11.9°, which indicates that the d-spacing is 0.7431 nm; atomic force microscopy showed a GO thickness of 200 nm. Fourier transform infrared spectra showed vibrations at 1624 cm-1 for the carbonyl groups, and 3260 cm-1 for the GO samples; the -C-O vibration was at 1320 cm-1 and -COOH, -OH vibrations were at 950 cm-1 . Fluorescent tests showed that pH had an impact on the QD colloidal stability. GO was neutralized before use as the host media for the GO/QDs nanocomposite. The results proved that the resultant nanocomposite is promising for use in brightness enhancement films in flexible displays.

Preparation of carbon quantum dots based high photostability luminescent membranes.

Urethane acrylate (UA) was used to prepare carbon quantum dots (C-dots) luminescent membranes and the resultants were examined with FT-IR, mechanical strength, scanning electron microscope (SEM) and quantum yields (QYs). FT-IR results showed the polyurethane acrylate (PUA) prepolymer -C = C-vibration at 1101 cm-1 disappeared but there was strong vibration at1687cm-1 which was contributed from the-C = O groups in cross-linking PUA. Mechanical strength results showed that the different quantity of C-dots loadings and UV-curing time affect the strength. SEM observations on the cross-sections of the membranes are uniform and have no structural defects, which prove that the C-dots are compatible with the water-soluble PUA resin. The C-dot loading was increased from 0 to 1 g, the maximum tensile stress was nearly 2.67 MPa, but the tensile strain was decreased from 23.4% to 15.1% and 7.2% respectively. QYs results showed that the C-dots in the membrane were stable after 120 h continuous irradiation. Therefore, the C-dots photoluminescent film is the promising material for the flexible devices in the future applications.

High Sensitivity Bacillus thuringiensis Cry1Ac Protein Detections Using Fluorescein Diacetate Nanoparticles.

A highly sensitive transgenic protein analysis method was proposed here based on fluorescein diacetate (FDA). First, FDA was prepared by the ball mill to harvest the nano-sized organic particles. Further examines showed that the FDA size can be controlled by the speed of centrifugation which can obtain FDA in well-distributed size. Cy3 antibody immobilization tests showed that the proteins can attach onto the FDA particles while keep bioactivities. FDA and Cry1Ac antibody immunoassay tests showed that when the FDA particle was in 150 nm, the linear range was 0.01 ng/L-30 µg/mL. And it has the lower detection limitation of 0.01 ng/L, which is 100 times more sensitive than the ELISA methods. These results indicate that the FDA related immunoassays are the promising approach in the transgenic analysis.

Do the cations in clay and the polymer matrix affect quantum dot fluorescent properties?

This paper studied the effects of cations and polymer matrix on the fluorescent properties of quantum dots (QDs). The results indicated that temperature has a greater impact on fluorescence intensity than clay cations (mainly K(+) and Na(+) ). Combined fluorescence lifetime and steady-state spectrometer tests showed that QD lifetimes all decreased when the cation concentration was increased, but the quantum yields were steady at various cation concentrations of 0, 0.05, 0.5 and 1 M. Poly(ethylene oxide) (PEO), poly(vinyl alcohol) (PVA) and diepoxy resin were used to study the effects of polymers on QD lifetime and quantum yield. The results showed that the lifetime for QDs 550 nm in PEO and PVA was 17.33 and 17.12 ns, respectively; for the epoxy resin, the lifetime was 0.74 ns, a sharp decrease from 24.47 ns. The quantum yield for QDs 550 nm changed from 34.22% to 7.45% and 7.81% in PEO and PVA, respectively; for the epoxy resin the quantum yield was 2.25%. QDs 580 nm and 620 nm showed the same results as QDs 550 nm. This study provides useful information on the design, synthesis and application of QDs-polymer luminescent materials. Copyright © 2015 John Wiley & Sons, Ltd.

A capillary based chemiluminscent multi-target immunoassay.

Renewed interest in capillary format immunoassays has lead to increasingly costly and complex approaches to preparation and readout. This study describes a simple multi-target method based on a capillary platform using horseradish peroxidase (HRP) labelled IgG to visualize an antibody antigen complex. When goat-anti-human IgG was employed as the probe and human IgG as target, the system allowed detection of target to less than 1 ng/mL using a standard detection approach. The capillaries were read visually or with a commercial grade CCD camera. Multi-target detection was demonstrated using a model system of rat-anti-mouse, goat-anti-human and mouse-anti-rat IgG. These probes were encoded to different locations in the capillary, providing a simple inexpensive approach to achieve multi-target assays.

Unraveling the impact of the design of current collector on dry-processed lithium-ion battery electrodes.

Dry processing emerges as a cost-effective technique for achieving high material loading in the field of lithium-ion battery fabrication. Nevertheless, insight into the role of current collectors in this process is still scarce. Herein, a set of dry-processed electrodes with three different current collectors is accordingly prepared and comprehensively studied. This work novelly reveals that the current collectors exhibit significant influence on the interface adhesion strength and the electron conductivity, which leads to difference in the mechanical strength and electrochemical performance of dry-processed electrodes. Consequently, it is recommended that carbon-coated current collector is preferred for dry-processed high energy density lithium-ion battery electrodes.

Recent progress of nano-drugs in neutron capture therapy.

As a developing radiation treatment for tumors, neutron capture therapy (NCT) has less side effects and a higher efficacy than conventional radiation therapy. Drugs with specific isotopes are indispensable counterparts of NCT, as they are the indespensable part of the neutron capture reaction. Since the creation of the first and second generations of boron-containing reagents, NCT has significantly advanced. Notwithstanding, the extant NCT medications, predominantly comprised of small molecule boron medicines, have encountered challenges such monofunctionality, inadequate targeting of tumors, and hypermetabolism. There is an urgent need to promote the research and development of new types of NCT drugs. Bio-nanomaterials can be introduced into the realm of NCT, and nanotechnology can give conventional medications richer functionality and significant adaptability. This can complement the advantages of each other and is expected to develop more new drugs with less toxicity, low side effects, better tumor targeting, and high biocompatibility. In this review, we summarized the research progress of nano-drugs in NCT based on the different types and sources of isotopes used, and introduced the attempts and efforts made by relevant researchers in combining nanomaterials with NCT, hoping to provide pivotal references for promoting the development of the field of tumor radiotherapy.

Biosafety assessments of hexafluoropropylene trimer derivative as a fluorinated cooling fluid for electronics.

The Internet Data Center (IDC) is one of the most important infrastructures in the field of information technology. The cooling system for heat dissipation of IDC is indispensable due to it generates a large amount of heat during its calculation process, which may potentially harm its normal operation. Electronic fluorinated fluids have been widely used in cooling systems of IDC with stable physical and chemical properties. However, the biological toxicity of electronic fluorinated fluids has not been fully evaluated and there is a lack of unified safety standards, which may pose potential risks to the environment and human health. Here, hexafluoropropylene terpolymer (HFPT) as an example has been systematically studied, fully considering the application scenarios of data centers. Also, the emergency effects of fluorinated coolants in mammalian models from the perspectives of inhalation, skin contact, accidental entry into eyes, accidental ingestion, and chronic toxicity, are evaluated. Multiple in vivo experiments have proven that HFPT not only has stable physical and chemical properties, that can maintain the safe operation of IDC, but also has low physiological toxicity to mammals and can provide health benefits to data center staff and the assurance of surrounding environment. This study proves the good biological safety of electronic fluorinated fluids and provides a reference for environmental assessment and risk management of liquid cooling technology in IDC. Supplementary Information: The online version contains supplementary material available at 10.1007/s43188-024-00234-3.