Polymerized Dopamine Research Articles

Development of Fe3O4/DEX/PDA@Au(Raman reporters)@Au-MPBA nanocomposites based multi-hotspot SERS probe for ultrasensitive, reliable, and quantitative detection of glucose in sweat

Glucose is a key biomarker of diabetes, and effective glucose monitoring methods are crucial to the prevention and management of diabetes. Therefore, in this paper, Fe3O4/DEX/PDA@Au (Raman reporters) @Au nanocomposites were synthetized that with DTNB (5,5′-dithiobis(2-nitrobenzoic)), MMTA (2-mercapto-4-methyl-5-thiazole acetic acid), MBA (4-mercaptobenzoic acid) and 4-Mpy(4-Mercaptopyridine) were used separately as Raman reporters. Fe3O4 and PDA (Polymerized dopamine) could supply more high surface area of active sites and high SERS (Surface-Enhanced Raman Scattering) substrate, which has high stability and reproducibility. Dextran coating is an effective way to prepare biocompatible materials TEM, XRD, TG and VSM were used to analyze the size, morphology and magnetic properties of the nanocomposites. Fe3O4/DEX/PDA@Au(Raman reporters)@Au that integrates a multi-hotspot structure and magnetic separation techniques were studied the enhancement effect of Raman spectra, and glucose solutions with different concentrations were tested. Furthermore, the optimal Fe3O4/DEX/PDA@Au(Raman reporters)@Au nanocomposites were supplied as SERS substrates for detection of glucose accurately and quickly in sweat. SERS signal intensity is linearly correlated with glucose concentration within the measurement range of 5 × 10-3 to 10 mM, and the minimum detectable concentration is 5 µM. The Fe3O4/DEX/PDA@Au(Raman reporters)@Au nanocomposites exhibit high reliability, specificity and repeatability of the strategy were then verified by practical detection of sweat.

Machine learning-assisted label-free colorectal cancer diagnosis using plasmonic needle-endoscopy system

Early and accurate detection of colorectal cancer (CRC) is critical for improving patient outcomes. Existing diagnostic techniques are often invasive and carry risks of complications. Herein, we introduce a plasmonic gold nanopolyhedron (AuNH)-coated needle-based surface-enhanced Raman scattering (SERS) sensor, integrated with endoscopy, for direct mucus sampling and label-free detection of CRC. The thin and flexible stainless-steel needle is coated with polymerized dopamine, which serves as an adhesive layer and simultaneously initiates the nucleation of gold nanoparticle (AuNP) seeds on the needle surface. The AuNP seeds are further grown through a surface-directed reduction using Au ions-hydroxylamine hydrochloride solution, resulting in the formation of dense AuNHs. The formation mechanism of AuNHs and the layered structure of the plasmonic needle-based SERS (PNS) sensor are thoroughly analyzed. Furthermore, a strong field enhancement of the PNS sensor is observed, amplified around the edges of the polyhedral shapes and at nanogap sites between AuNHs. The feasibility of the PNS sensor combined with endoscopy system is further investigated using mouse models for direct colonic mucus sampling and verifying noninvasive label-free classification of CRC from normal controls. A logistic regression-based machine learning method is employed and successfully differentiates CRC and normal mice, achieving 100% sensitivity, 93.33% specificity, and 96.67% accuracy. Moreover, Raman profiling of metabolites and their correlations with Raman signals of mucus samples are analyzed using the Pearson correlation coefficient, offering insights for identifying potential cancer biomarkers. The developed PNS-assisted endoscopy technology is expected to advance the early screening and diagnosis approach of CRC in the future.

A first look at the formation of PEO-PDA coatings on 3D titanium

Additive manufacturing has revolutionized implantology by enabling the fabrication of customized, highly porous implants. Surface modifications using electrochemical methods can significantly enhance the bioactivity and biocompatibility of biomaterials, including 3D-printed implants. This study investigates novel coatings on 3D titanium (Ti) samples. Mesh Ti samples were designed and subjected to plasma electrolytic oxidation (PEO) to form a calcium phosphate coating. Subsequently, a layer of polydopamine (PDA) was applied. The electrochemical properties and morphology of the coatings were analyzed. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) revealed well-developed coatings containing calcium phosphates (including hydroxyapatite), titanium dioxide, and polymerized dopamine, suggesting promising bioactive potential. Composite layers incorporating PDA exhibited superior protective properties compared to base PEO coatings.

Design, optimization, and evaluation of methotrexate loaded and albumin coated polymeric nanoparticles

Methotrexate is a potent anticancer drug whose strong efflux is facilitated by the brain’s efflux transporter. As an efflux transporter blocker, albumin increased the drug’s concentration in the brain. Methotrexate-loaded nanoparticles were produced by evaporating the emulsification fluid. Improvements and analyses were made to the following aspects of the generated nanoparticles: size, polydispersity, zeta potential, entrapment efficiency, percentage yield, scanning electron microscopy, in vitro drug release studies, and sterilization. The particle size was determined to be in the nano range, and homogeneity of particle size was suggested by a low polydispersity index result. Particle diameters of 168 nm were observed in the F5 preparation, and zeta potential values of −1.5 mV suggested that the preparation produced adequate repulsive interactions between the nanoparticles. Albumin and dopamine HCl were employed to coat the methotrexate-loaded nanoparticles to guarantee that the brain received an adequate amount of them. The homogeneity of albumin coated nanoparticles was demonstrated by the low% PDI values of 0.129 and 0.122 for albumin coated nanoparticles (MNPs-Alb) and polymerized dopamine HCl and albumin coated nanoparticles (MNPs-PMD-Alb), respectively. After 48 h of incubation, the cell viability measured at the same drug concentration (5 mg) decreased for the F5, albumin coated nanoparticles, polymerized dopamine HCl coated nanoparticles, and polymerized dopamine HCl and albumin coated nanoparticles, respectively. Our primary findings demonstrate that the albumin nanoparticles containing methotrexate are designed to deliver the drug gradually. With minimal cytotoxicity, the intended preparation might give the brain an appropriate dosage of methotrexate.

Electrochemically polymerized dopamine activated carbon paste sensor for selective and sensitive detection of rutin in the presence of riboflavin

In this work, a sensor was developed for the quantification of RT in food and medicine samples using electro-polymerization of dopamine (DA) on the surface of a carbon paste electrode in 0.2 M phosphate buffered saline (PBS) of 7.0 pH by cyclic voltammetry (CV). The surface properties of bare carbon paste electrode (BCPE) and poly (DA) modified carbon paste electrode (PDAMCPE) were studied using scanning electron microscopy (SEM), electrochemical impedance study (EIS), and CV techniques. Two electron two proton transfer process was seen during the electrochemical reaction of RT with adsorption-controlled process. Under optimum conditions, the peak current increased linearly with an increase in RT concentration for CV in the range of 0.4 to 2.0 μM and differential pulse voltammetry (DPV) in the range of 0.4 to 2.5 μM and the limit of detection (LOD) was found to be 0.0045 μΜ and for CV and 0.079 μM for DPV techniques respectively. Even in the presence of some interferents like organic compounds and metal ions, the developed electrode exhibits good anti-interference ability for RT, and good selectivity was obtained for RT in the presence of riboflavin (RF). The developed sensor presents good stability, repeatability, and reproducibility. The CV measurement was performed for the analysis of RT in real samples such as green tea and medicine samples which showed a good recovery and this work has been not reported previously.

Corals-inspired magnetic absorbents for fast and efficient removal of microplastics in various water sources.

Microplastics (MPs) as the formidable pollutants with high toxicity and difficult degradation may threaten the aquaculture industry and human health, making it highly necessary to develop the effective removal methods. In this article, Fe3O4 nanoparticles (NPs) were initially fabricated with mesoporous structure, but showing undesirable adsorption efficiencies for the adsorption of MPs (lower than 70%). Inspired by the reefs-rebuilding corals acting as the sinks for various marine pollutants like plastic, Fe3O4 NPs were coated further with adhesive polymerized dopamine (PDA) yielding Fe3O4@PDA absorbents. Unexpectedly, it was discovered that the corals-mimicking absorbents so formed could allow for the removal of MPs with dramatically enhanced efficiencies up to 98.5%, which is over about 30% higher than those of bare Fe3O4 NPs. Herein, the PDA shells might conduct the increased adhesion to MPs, presumably through the formation of hydrogen bonding, π-π stacking, and hydrophobic interactions. A fast (within 20 min) and stable adsorption of MPs can also be expected, in addition to the PDA-improved environmental storage of Fe3O4 NPs. Subsequently, the Fe3O4@PDA adsorbents were utilized to remove MPs from different water sources with high efficiencies, including pure water, suburban streams, village rivers, lake water, inner-city moats, and aquaculture water. Such a magnet-recyclable adsorbent may provide a new way for rapid, effective, and low-cost removal of MPs pollutants from various water systems.

Highly efficient uranium (VI) remove from aqueous solution using nano-TiO2-anchored polymerized dopamine-wrapped magnetic photocatalyst

Radioactive uranium containing wastewater discharged from uranium mining and associated nonferrous metallurgy posing a serious threat to human health and aquatic ecosystem. In this paper, we attempted to use photocatalytic technology to reduction U(VI) from diluted uranium-containing wastewater and recover dispersed uranium by constructing a highly efficient photocatalyst. A polymerized dopamine (PDA)-wrapped magnetic base was introduced to support spherical anchoring of TiO2 nanoparticles, and the newly designed photocatalyst (TiO2/PDA@Fe3O4) with a particle size of 450∼700 nm had a remarkable multilayer-ball structure and displayed remarkably high recyclability and photocatalytic reduction efficiency for aqueous uranium under UV radiation. Uranyl with an initial concentration of 2.0 mg/L, and solution pH of 6.0 was ∼100% removed within 40 min, and no interference by coexisting anionic and cation ions was not observed. In determination of photocatalytic mechanism, the results showed that nanoscale TiO2 particles on TiO2/PDA@Fe3O4 surface can adsorb U(VI) efficiently and reducing them under UV radiation. Furthermore, TiO2/PDA@Fe3O4 nanocomposites displayed high stability performance, the uranium removal efficiency was greater than 83.5% after six times recycle. The proposed engineered interface fabricate strategy has the potential for use in universal hydro-stable micro/nano-particle production and may contribute to more effective uranium extraction from waste liquids.

Polydopamine Derived NaTi2(PO4)3-Carbon Core-Shell Nanostructures for Aqueous Batteries and Deionization Cells.

Due to their stability and structural freedom, NASICON-structured materials such as NaTi2(PO4)3 show a lot of promise as active electrode materials for aqueous batteries and deionization cells. However, due to their low intrinsic electronic conductivity, they must usually be composited with carbon to form suitable electrodes for power applications. In this work, two series of NaTi2(PO4)3-carbon composite structures were successfully prepared by different approaches: postsynthetic pyrolytic treatment of citric acid and surface polymerized dopamine. The latter route allows for a superior carbon loading control and yields more uniform and continuous particle coatings. The homogeneity of the polydopamine derived core-shell carbon layer is supported by FTIR, TEM, and XPS analysis. Combustion elemental analysis also indicates significant nitrogen doping in the final carbonaceous structure. The galvanostatic charge and discharge cycling results show similar initial capacities and their retention, but at only half of the carbon loading in polydopamine derived samples. The overall results indicate that careful nanostructure engineering could yield materials with superior properties and stability suitable for various electrochemical applications such as aqueous Na-ion batteries and deionization cells.

In situ construction of Fe3O4@PDA@Au multi hotspot SERS probe for trace detection of benzodiazepines in serum

The abuse of benzodiazepines is a serious health hazard that can cause damage to the central nervous system.Trace monitoring of benzodiazepines in serum can effectively prevent the damage caused by these drugs. Therefore, in this study, a Fe3O4@PDA@Au core–shell satellite nanomaterial SERS(Surface-Enhanced Raman Scattering) probe that integrates magnetic separation techniques and a multi-hotspot structure was synthetized by in situ growth of gold nanoparticles on the surface of PDA(Polymerized dopamine)-coated Fe3O4. The size and gap of Au nanoparticles on the surface of the SERS probe can be modulated by regulating the amount of HAuCl4 to create 3D multi-hotspot structures. The good dispersion and superparamagnetic properties of this SERS probe enable it to fully contact and load the target molecules in the serum, and the applied magnetic field facilitates separation and enrichment.This process increases the molecular density and number of SERS hotspots, thereby enhancing detection sensitivity. Based on the above considerations, this SERS probe can detect traces of eszopiclone and diazepam in serum at concentrations as low as 1 μg/ml with good linearity, offering promising applications in clinical monitoring of drug concentrations in blood.

Multi-energies assisted and all-weather recovery of crude oil by superhydrophobic melamine sponge.

Efficient and safe recovery of high-viscosity marine crude oil spills is still a worldwide challenge. High-viscosity crude oil is difficult to be removed by traditional adsorbent materials. Although some recent developments in photothermal or electric-thermal oil-absorbing materials, the vertical heat transfer inside and the potential hazard of electrical leakage are difficult to be guaranteed. In order to overcome these problems, we polymerized dopamine (DA) in situ on the skeleton surface of the commercial melamine sponge (MS), and further coated the full-wavelength light-absorbing Fe3O4 NPs-Graphene (HF-G) on it to obtain the superhydrophobic sponge with excellent photothermal conversion effect, heat conductivity and magnetic heating capabilities (HF-G/PDA@MS). When the thickness of sponge is 5mm, the HF-G/PDA@MS shows excellent vertical heat conductivity ability, and can absorb about 80g/g. It also can be combined with an extra electric-heating device to achieve continuous heating to reduce the viscosity and recover crude oil at night or extreme weather. In addition, the temperature of HF-G/PDA@MS can reach about 40°C by electromagnetic induction heater, indicating that we can use multiple energies-assisted modes to heat the HF-G/PDA@MS to. This work provides a promising solution and theoretical support for all-weather solving offshore crude oil spills pollution and recovery.

Multifunctionalization of PTFE membrane surface for biofouling resistance and oil/water separation performance improvement

Polytetrafluoroethylene (PTFE) is considered as one of the most promising membrane materials for oil-water separation, mainly because of its excellent chemical and mechanical stability. But its inherent strong hydrophobicity, which can cause the membrane easy fouled by bacteria, limits the application of PTFE membrane. We designed a new surface modification approach, through which hydrophilic and antibacterial PTFE membranes can be fabricated conveniently by combining polymerized dopamine (PDA) and thiolactone chemistries. A copolymer (P(DMAEMA-co-TlaAm)) containing thiolactone and tertiary amine moieties were synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization and attached onto the PDA coated PTFE membrane surface, together with glucosamine, via the thoilactone chemistry. Due to efficient glycosylation, the membrane exhibits great hydrophilicity. Water contact angle of the membrane surface dropped from 123° to 13°. Pure water flux of the membrane reached 2490 L m−2 h−1 bar−1, which is 2.7 times that of the original membrane. Also, the separation efficiency of the iso-paraffin emulsion reached 97.5 % at a membrane flux of 90 L m−2 h−1 bar−1. Notably, in addition to the hydrophilicity provided by glucosamine, the modified membranes also showed decent antibacterial property because of the introduction of tertiary amine groups. The bacteria inhibition rate against Staphylococcus aureus reached 99 %.

An MMP-degradable and conductive hydrogel to stabilize HIF-1α for recovering cardiac functions.

Rationale: Although a few injectable hydrogels have shown a reliable biosafety and a moderate promise in treating myocardial infarction (MI), the updated hydrogel systems with an on-demand biodegradation and multi-biofunctions to deliver therapeutic drug would achieve more prominent efficacy in the future applications. In this report, a conductive and injectable hydrogel crosslinked by matrix metalloproteinase-sensitive peptides (MMP-SP) was rationally constructed to stabilize hypoxia-inducible factor-1α (HIF-1α) to recover heart functions after MI.Methods: Firstly, tetraaniline (TA) was incorporated into partially oxidized alginate (ALG-CHO) to endow the hydrogels with conductivity. The 1,4-dihydrophenonthrolin-4-one-3-carboxylic acid (DPCA) nanodrug was manufactured with high drug loading capacity and decorated with polymerized dopamine (PDA) to achieve a stable release of the drug. Both ALG-CHO and DPCA@PDA can be cross-linked by thiolated hyaluronic acid (HA-SH) and thiolated MMP-SP to construct a MMP-degradable and conductive hydrogel. After administration in the infarcted heart of rats, echocardiographic assessments, histological evaluation, and RT-PCR were used to evaluate therapeutic effects of hydrogels.Results: The cell viability and the results of subcutaneous implantation verify a good cytocompatibility and biocompatibility of the resulting hydrogels. The hydrogel shows remarkable strength in decreasing the expression of inflammatory factors, maintaining a high level of HIF-1α to promote the vascularization, and promoting the expression of junctional protein connexin 43. Meanwhile, the multifunctional hydrogels greatly reduce the infarcted area (by 33.8%) and improve cardiac functions dramatically with ejection fraction (EF) and fractional shortening (FS) being increased by 31.3% and 19.0%, respectively.Conclusion: The as-prepared hydrogels in this report achieve a favorable therapeutic effect, offering a promising therapeutic strategy for treating heart injury.

Modified porous carboxymethyl chitin microspheres by an organic solvent-free process for rapid hemostasis

Rapid and effective hemorrhage control is essential to reduce mortality following traumatic injuries. Herein we developed an organic solvent-free process to prepare carboxymethyl chitin microsphere (CMCHm) in an aqueous two-phase system through heating and freeze-drying. To further enhance the hemostatic performance of CMCHm, we loaded calcium ions and in-situ polymerized dopamine to get modified hemostatic microspheres CMCHm-Ca2+ and CMCHm-PDA, respectively. The size of these microspheres was mainly distributed between 50 μm and 150 μm, and the porous microstructure was observed by SEM. The data of in vitro degradation, cell cytotoxicity, and hemolysis test indicated good biocompatibility of these microspheres. Importantly, CMCHm-Ca2+ and CMCHm-PDA displayed better hemostatic performance compared with CMCHm and the positive controls Yunnan baiyao® and Quickclean®. Especially, the bleeding time was reduced to 59 s (CMCHm-Ca2+) and 45 s (CMCHm-PDA) in the femoral artery/vein cut model, respectively. All these demonstrate CMCHm-Ca2+ and CMCHm-PDA hold great potential for rapid hemostasis.

Biomimetic Nanopillar-Based Biosensor for Label-Free Detection of Influenza A Virus.

Since the first emergence of influenza viruses, they have caused the flu seasonally worldwide. Precise detection of influenza viruses is required to prevent the spreading of the disease. Herein, we developed an optical biosensor using peptide-immobilized nanopillar structures for the label-free detection of influenza viruses. The spin-on-glass nanopillar structures were fabricated by nanoimprint lithography. A sialic acid-mimic peptide, which can specifically bind to hemagglutinin on the surface of the influenza virus, was immobilized onto the nanopillars via polymerized dopamine. The constructed nanopillar sensor enabled us to detect influenza A viruses in the range of 103–105 plaque-forming units through simple measurements of reflectance. Our findings suggest that biomimetic modification of nanopillar structures can be an alternative method for the immunodiagnosis of influenza viruses.

Identification of Novel FNIN2 and FNIN3 Fibronectin-Derived Peptides That Promote Cell Adhesion, Proliferation and Differentiation in Primary Cells and Stem Cells.

In recent years, a major rise in the demand for biotherapeutic drugs has centered on enhancing the quality and efficacy of cell culture and developing new cell culture techniques. Here, we report fibronectin (FN) derived, novel peptides fibronectin-based intergrin binding peptide (FNIN)2 (18-mer) and FNIN3 (20-mer) which promote cell adhesion proliferation, and the differentiation of primary cells and stem cells. FNIN2 and 3 were designed based on the in silico interaction studies between FN and its receptors (integrin α5β1, αvβ3, and αIIbβ3). Analysis of the proliferation of seventeen-cell types showed that the effects of FNINs depend on their concentration and the existence of expressed integrins. Significant rhodamine-labeled FNIN2 fluorescence on the membranes of HeLa, HepG2, A498, and Du145 cells confirmed physical binding. Double coating with FNIN2 or 3 after polymerized dopamine (pDa) or polymerized tannic acid (pTA) precoating increased HBEpIC cell proliferation by 30–40 percent, suggesting FNINs potently affect primary cells. Furthermore, the proliferation of C2C12 myoblasts and human mesenchymal stem cells (MSCs) treated with FNINs was significantly increased in 2D/3D culture. FNINs also promoted MSC differentiation into osteoblasts. The results of this study offer a new approach to the production of core materials (e.g., cell culture medium components, scaffolds) for cell culture.

Two‐Dimensional Polydopamine Positive Electrodes for High‐Capacity Alkali Metal‐Ion Storage

AbstractRedox‐active organic compounds have attracted substantial attention as charge storage materials, owing to their high theoretical capacity. Herein, a two‐dimensional organic electrode material is prepared by using hydrothermally polymerized dopamine molecules on graphene nanosheets. Two‐dimensional polydopamine is employed as a positive electrode for storing alkali metal ions based on the surface redox reaction between oxygen functional groups and alkali ions. The two‐dimensional polydopamine positive electrodes deliver high capacities of 255 mAh g−1 in Li cells, 150 mAh g−1 in Na cells, and 124 mAh g−1 in K cells at 0.1 A g−1, demonstrating a promising organic positive electrode for rechargeable alkali‐ion batteries.

Achieving maximum recovery of latent heat in photothermally driven multi-layer stacked membrane distillation

Photothermal membrane distillation (PMD) has received increased attention for water desalination because it uses abundant sunlight as its main energy source. It can also be implemented in a modular configuration and work well for decentralized communities. Here we present a multi-layer stacked membrane module with airgaps that can reduce conductive heat loss and recover latent heat. The membrane is synthesized by a simple and scalable spray-coating method that prepared by graphene nanosheets deposition onto a hydrophobic polytetrafluoroethylene (PTFE) membrane with polymerized dopamine (PDA) and trichloro(1H,1H,2H,2H-perfluorooctyl) silane (FTCS). Graphene nanosheets are employed as a photothermal material because of its broad light absorption in the solar spectrum and efficient photothermal conversion. To maximize the water flux, the airgap thickness was optimized, and multiple heat recovery layers were stacked. Using the optimized airgap and four stacked layers, we achieved a high water flux of 1.17 kg/m 2 /h under 0.75 kW/m 2 , equivalent to 105% solar conversion efficiency, which is the highest efficiency reported among all PMD studies (20–70%). To predict the water flux, we further constructed a theoretical model to estimate the membrane surface temperatures that are photothermally heated, which will be helpful in understanding and optimizing future PMD systems. The high efficiency of the multi-layer stacked PMD module in this study bespeaks its great promise as a sustainable and off-grid desalination technique. With an efficient graphene nanosheet-based photothermal membrane, we demonstrate that the performance of the photothermal membrane distillation was largely improved by effectively recovering latent heat generated during condensation of vapor. Using the optimized airgap and four stacked layers, we achieved a high water flux of 1.17 kg/m 2 /h under 0.75 kW/m 2 , equivalent to 105% solar conversion efficiency. • Graphene-based photothermal membranes were fabricated with a simple spray coating. • In our novel multi-layer stacked module, latent heat was efficiently recovered. • With an optimal setting, we achieved the high solar-to-water efficiency (~ 105%). • Synthesized membranes were mechanically and chemically robust for long-term use.

In situ infrared spectroscopy of dopamine oxidation/reduction reactions on a polycrystalline boron-doped diamond electrode

The oxidation of dopamine (DA) on a boron-doped diamond (BDD) electrode was investigated using in situ attenuated total reflection infrared spectroscopy (ATR-IR) and infrared reflection absorption spectroscopy (IRAS). Voltammogram showed multiple anodic/cathodic peaks for the oxidation/reduction of DA and its oxidized derivatives on the BDD electrode. The oxidation/reduction species on the surface and in solution were assigned using ATR-IR and IRAS, respectively. The anodic oxidation of DA promoted polymerization, and the polymerized DA (PDA) was continuously deposited on BDD without being reduced by potential cycles, which resulted in the irreversible behavior of the voltammogram. A decrease in the oxidation current of DA by potential cycles was due to the deposition of PDA. Some intermediate quinone species, such as dopaminequinone and dopaminechrome, were reversibly reduced to hydroquinone.

Enhanced ion transport in PVDF-HFP gel polymer electrolyte containing PDA@BN for lithium ion batteries

Boron nitride nanosheet (BN) modified by polymerized dopamine (PDA@BN) was incorporated into PVDF-HFP gel polymer electrolyte (GPE) by solution casting method. PDA@BN can improve the ionic conductivity (2.26 × 10−3 S cm−1 at 30 °C), the electrochemical stability of GPE (electrochemical window is 5.0 V) and effectively inhibit the growth of lithium dendrites because of barrier effect of two-dimensional BN. The cell prepared with 3PVDF-HFP/5[EMIM][TFSI]/2LiTFSI+6%PDA@BN (3P5E2L+6%PDA@BN) GPE presents excellent cycle performance. The LiFePO4/3P5E2L + 6%PDA@BN/Li cells exhibited more than 99% columbic efficiency and the initial discharge capacity reached the maximum of 162.9 mAh/g, capacity retention was about 85% after 80 cycles at 0.1C. The excellent performance of this GPE implies that it can be applied to high-safety and long-cycle life lithium metal batteries.

Ultrathin and stable graphene oxide film via intercalation polymerization of polydopamine for preparation of digital inkjet printing dye

As a result of distinctive nanopores of two-dimensional material, graphene oxide (GO) has emerged as a new-generation membrane for high performance water separation. However, GO-based composed membrane applied to dye desalting gains less attention. A series of novel ultrathin and stable polydopamine/graphene oxide (PGO) membranes has been successfully fabricated via intercalation polymerization of dopamine using triple vacuum filtration. The polymerized dopamine (PDA) via intercalation polymerization in the interspace between the lamellar layers is used to simultaneously improve the stability of GO film and rapid passage of ions. The high permeation of pure water of as-prepared PGO membranes is investigated through adjusting the thickness (9–126 nm) of modified layers. In addition, the values decrease from 24.2 to 0.65 L m−2 h−1 bar−1 with increasing the layer. With the ultrafast ion transport and dyes rejection under cross-flow condition, the stability PGO membranes show a good capability for desalination dyes and concentration of dye (11.6 times of the initial dye solution).