Liquid-phase Method Research Articles

A silver and manganese dioxide composite with oxygen vacancies as a high-performance cathode material for aqueous zinc-ion batteries.

Aqueous zinc ion batteries (AZIBs) are regarded as a promising alternative for energy storage due to their safety, cost-effectiveness and environmental friendliness. Manganese dioxide is considered a promising cathode material for energy storage because of its abundant reserves and high energy density. However, its inherent low electronic conductivity and limited cycling performance due to structural instability hinder its further development. Herein, a silver and manganese dioxide composite (Ag@MnO2) enriched with oxygen vacancies was prepared by a simple liquid-phase reduction method. The introduction of silver particles facilitates the improvement of electrical conductivity, and the incorporation of oxygen vacancies helps change the surface properties of manganese dioxide, providing additional active sites for ion transport, enhancing the overall electrochemical kinetics, and further improving the battery performance. As a result, the Ag@MnO2 cathode exhibits an astonishingly high capacity of 353 mAh g-1 at a current density of 0.1 A g-1 and a capacity retention of 78% after 1500 cycles. Additionally, electrochemical and structural analyses have revealed that the Ag@MnO2 cathode undergoes a reversible and stable process of H+ and Zn2+ insertion/extraction.

Responsive ZIF-90 nanocomposite material: targeted delivery of 10-hydroxycamptothecine to enhance the therapeutic effect of colon cancer (HCT116) cells.

There is significant value in developing multifunctional drug delivery systems with high therapeutic efficiency for diagnosing and treating tumors. In this study, we synthesized the ATP-triggered and pH-sensitive material ZIF-90 using the liquid-phase diffusion method. This was done to load 10-hydroxycamptothecin (HCPT), and the FA-PEG-NH2 conjugate was synthesized through an amidation reaction. We further modified the HCPT@ZIF-90 nanocomposite by employing the Schiff base reaction to create the HCPT@ZIF-90-PEG-FA nanomaterial. Drug loading test results revealed a high HCPT drug loading of up to 22.3% by weight. In the drug release experiment, the cumulative drug release of HCPT@ZIF-90 nanomaterials in pH 5.4 and ATP solutions was the highest after 72 hours. The active targeted delivery of FA and the dual-responsive release of HCPT by ZIF-90 significantly enhanced the therapeutic effect of HCPT@ZIF-90-PEG-FA on human colon cancer cells (HCT116). In the cytotoxicity test, when 100 μg mL-1 of HCPT@ZIF-90-PEG-FA was incubated with cells, the cell survival rate was 16.61 ± 1.19%, significantly lower than that of the other experimental groups. This result indicates that HCPT@ZIF-90-PEG-FA exhibits excellent anti-tumor activity. Cell cycle experiments have shown that HCPT@ZIF-90-PEG-FA may inhibit the proliferation of cancer cells by blocking DNA synthesis and halting cell cycle progression. Cell uptake experiments showed that HCPT@ZIF-90-PEG-FA was mainly present in the cytoplasm of HCT1116 cells, indicating successful cellular entry of the drug to exert its therapeutic effect. In vivo experiments also demonstrated that HCPT@ZIF-90-PEG-FA nanomaterials can effectively eradicate HCT116 tumors. The utilization of the nano-drug carrier ZIF-90, along with the modification with PEG-FA, notably improved the therapeutic efficacy of HCPT. These results suggest that the system, with its active targeted delivery of FA and dual-responsive release of HCPT, could present a novel strategy for treating human colorectal cancer.

Bandgap regulation and doping modification of Ga2-x Cr x Se3 nanosheets.

Ga2Se3, an important direct wide bandgap semiconductor with excellent optoelectronic properties, has wide application potential in the fields of photodetectors, photoelectric sensors and solar cells. Herein, we describe the synthesis of Ga2Se3 semiconductor nanoparticles using a high temperature organic liquid phase method. Post-annealing treatment at different temperatures can not only improve the crystallinity of Ga2Se3 nanoparticles, but also regulate its optical band gap ranging from 2.50 to 2.80 eV. We further synthesized Ga2-x Cr x Se3 nanosheets by doping CrCl3·6H2O in the reaction process. By adjusting the Cr doping concentration, Ga2-x Cr x Se3 nanosheets can achieve a continuously tunable band gap in the range of 2.23 eV to 2.42 eV. Both Ga2-x Cr x Se3 nanosheets and Ga2Se3 nanoparticles exhibit excellent and stable photoelectric switching performance. With Cr doping, Ga2-x Cr x Se3 exhibits reduced Nyquist impedance and enhanced electrocatalytic activity, which is attributed to its ultrathin nanosheet morphology and large specific surface area. In addition, the diamagnetic behavior of pure Ga2Se3 changes to ferromagnetism with different Cr doping concentrations, and its magnetization is as high as 18.0 emu g-1 at x = 0.4. These findings demonstrate that Ga2-x Cr x Se3 nanosheets have significant potential in future optoelectronic and magnetoelectric applications.

High-performance flexible resistive random-access memory based on SnS2 quantum dots with a charge trapping/de-trapping effect.

The application of resistive random-access memory (RRAM) in storage and neuromorphic computing has attracted widespread attention. Benefitting from the quantum effect, transition metal dichalcogenides (TMD) quantum dots (QDs) exhibit distinctive optical and electronic properties, which make them promising candidates for emerging RRAM. Here, we show a high-performance forming-free flexible RRAM based on high-quality tin disulfide (SnS2) QDs prepared by a facile liquid phase method. The RRAM device demonstrates high flexibility with a large on/off ratio of ∼106 and a long retention time of over 3 × 104 s. The excellent switching behavior of the memristor is elucidated by a charge trapping/de-trapping mechanism where the SnS2 QDs act as charge trapping centers. This study is of significance for the understanding and development of TMD QD-based flexible memristors.

Synthesis of Cobalt Particles and Investigation of Their Electromagnetic Wave Absorption Characteristics.

As the integration technology for integrated circuit (IC) packaging continues to advance, the issue of electromagnetic interference in IC packaging becomes increasingly prominent. Magnetic materials, acknowledged for their superior electromagnetic absorption capabilities, play a pivotal role in mitigating electromagnetic interference problems. In this study, we employed a liquid-phase reduction method. We prepared three types of cobalt (Co) particles with distinct morphologies. Through variations in the synthesis process conditions, we were able to control the aspect ratio of protrusions on the surface of the Co particles. It was found that the sword-like Co particles exhibit superior electromagnetic wave absorption capabilities, showing a reflection loss value of up to -50.96 dB. Notably, when the coating thickness is only 1.6 mm, the effective absorption bandwidth is extended up to 7.6 GHz. The spatially expansive sword-like Co particles, with their unique structure featuring dipole polarization and interfacial polarization, demonstrated enhanced dielectric and magnetic loss capabilities, concurrently showcasing superior impedance-matching performance.

Dielectric and Magnetic Composites of Fe3O4@APNs for Superior Microwave Thermal Effect.

As for the deep tissue infections of chronic osteomyelitis, antibiotics are hard to deliver into the infected bone tissue, which makes it difficult to be cured completely in clinic. Microwave has strong penetration, and the medium can produce a good bactericidal effect through the microwave thermal effect (MTE). Here, a new microwave sensitizer (Fe3O4@APNs) was prepared and evaluated. Black phosphorus nanosheets modified with phytic acid dodecasodium (APNs) were fabricated by a liquid-phase exfoliation method that exhibited good water oxygen stability. A complex with Fe3O4 compound and APNs (Fe3O4@APNs) was formed by an ultrasonic mixing process, which showed excellent MTE (quickly increased to 53.5 °C in 5 min at 2.45 GHz, 10 W/cm2) via dielectric versus magnetic loss (reflect loss value of -5.94 dB at 2.45 GHz). The Fe3O4@APNs microwave sensitizer developed in this study has an outstanding in vitro antibacterial effect and might show promise for the treatment of chronic osteomyelitis enabled by local tissue heating via the MTE.

Construct 2D/1D BiOX (X = Cl, Br)@Bi5O7I heterojunctions with rich interfaces and wide visible light response range for pollutant removal in water under LED light

At present, the development of photocatalysts with high visible light sensitivity and efficient catalytic activity for environmental pollution control is the focus of research in the field of photocatalysis. In this work, 2D/1D BiOX (X = Cl, Br)@Bi5O7I heterojunction with abundant interfaces was prepared by a low-temperature liquid-phase method using Bi5O7I nanorods as substrate and BiOX nanoflakes as shell. The rich interfaces can be used as transport bridge for photogenerated electrons between Bi5O7I and BiOX. Under the optimum condition of BiOX content of 60%, the surface charge transfer efficiency increased from 20.79% (Bi5O7I) to 55.44% (BOI-BC-60) and 67.36% (BOI-BC-60) according to the photoelectrochemical measurement results. In the application of photocatalytic degradation of levofloxacin, the prepared BiOX (X = Cl, Br)@Bi5O7I heterojunctions exhibited enhanced adsorption capacity in darkness and improved photocatalytic activity under visible light. The reaction rate and pollutant removal efficiency of BOI-BC-60 and BOI-BB-60 were 6.87, 2.07 and 12.17, 3.28 times higher than that of Bi5O7I, respectively. It is proved that the suitable valence band and conduction band positions of BiOX and Bi5O7I components in BiOX@Bi5O7I heterojunction provide thermodynamic conditions for the migration of photogenerated electrons and holes.

Liquid-Phase Synthesis of the Li–Si–P–S–Cl Solid Electrolyte for All-Solid-State Li-Ion Battery

Sulfide solid Li-ion conductors can be applied as electrolytes for high-performance all-solid-state batteries. For establishing mass production of such sulfides, liquid-phase synthesis is an attractive alternative to conventional solid-state method. Nevertheless, the new method has only been adapted to limited compositions (i.e., the Li–P–S system) with resulting in low ionic conductivity values of < 1.5 mS cm−1 at room temperature1. This study reports the liquid-phase synthesis of solid electrolytes in the Li–Si–P–S–Cl system (Li9.54Si1.74P1.44S11.7Cl0.3: LSiPSCl)2 with the high ionic conductivity of 6.6 mS cm-1 at 298 K3.In liquid-phase method, it is essential to find appropriate dissolution conditions without decomposition reactions of the raw materials, but such conditions have not been found for Si. We investigated the dissolution conditions of Si in anhydrous acetonitrile (ACN), which typically promotes severe decomposition reactions of dissolved raw materials. However, it was found that SiS2 is highly soluble in ACN when mixed with Li2S in specific molar ratio. This composition was confirmed by ICP-AES, wherein the molar ratio of Si : Li in the homogeneous solution was determined to be 1:1. Based on this finding, LSiPSCl was synthesized by the liquid-phase approach (Fig. 1a). Two homogeneous solutions containing either (Li, Si, and S) or (Li, P, and S)4 were prepared separately and then combined. Subsequently, LiCl and Li2S were added to obtain the precursor slurry solution. The precursor slurry solution was dried at 453 K under vacuum to remove all the solvent and sintered by heating at 748 K to obtain the liquid-phase synthesized sample (L-LSiPSCl).The L-LSiPSCl exhibited high ionic conductivity of 6.6 mS cm-1 at 298 K, which was comparable to the value for the reference sample (S-LSiPSCl) synthesized by the solid-state method. All-solid-state battery cells were prepared to examine the applicability of L-LSiPSCl as a solid electrolyte (Fig. 1b), with In–Li alloy anode and the composite cathode consisting of L-LSiPSCl (or S-LSiPSCl) and LiNbO3-coated LiCoO2. The charge–discharge cycle was conducted at the current density of 0.096 mA cm-2, which corresponds to 0.2 C rate. After 100 cycles, the discharge capacity for the cell with L-LSiPSCl was 88% of its theoretical value (i.e., 137 mA h g-1 for 1.9–3.6 V vs. Li+ /In–Li), and its capacity retention was > 97%. The charge–discharge performance was slightly better than that of the cell with S-LSiPSCl. The possible slight improvement might be attributed to the characteristic particle properties of L-LSiPSCl; scanning electron microscopy and micro-Raman spectroscopy indicated L-LSiPSCl is composed of aggregated particles with pores and carbides on particle surface. Overall, this study expanded the applicability of liquid-phase synthesis and implied its potential merits for sulfide Li-ion conductors for all-solid-state batteries.Reference1) A. Miura et al., Nat. Rev. Chem., 3, 189 (2019)2) Y. Kato et al., Nat. Energy, 1, 16030 (2016)3) T. Ito et al., J. Mater. Chem. A, 10, 14392 (2022)4) M. Calpa et al., Chem. Mater., 32, 9627 (2020) Figure 1

Structural regulation of asphalt-based hard carbon microcrystals based on liquid-phase crosslinking to enhance sodium storage

Air-oxidation is an effective strategy to obtain promising carbon materials from asphalt for sodium-ion batteries. However, this method would generate a vast amount of gaseous pollutant, which pose challenges for recycling. Herein, a simple, cost-effective and environmentally friendly liquid-phase oxidation method is proposed. The oxygen-containing functional groups (-NO2) are introduced into asphalt, which effectively prevents the melting of asphalt and rearrangement of carbon layers during subsequent carbonization process. As a result, a carbon material with notable disorder degree, large interlayer spacing and abundant closed pores, is prepared. The as-prepared product demonstrates an impressive initial Coulombic efficiency of 88.3 % and an enhanced specific capacity of 317.0 mA h g−1, which is 2.6 times that of the pristine product. Moreover, when assembled with a Na3.32Fe2.34(P2O7)2 cathode, the full-cell delivers a high reversible capacity of 271.7 mA h g−1 at 30 mA g−1 with superb cycle life. This study offers a novel oxidation strategy and provides a solution for producing highly disordered carbon anodes from soft carbon precursors.

ИССЛЕДОВАНИЕ ТРИБОТЕХНИЧЕСКИХ СВОЙСТВ КОМПОЗИЦИОННОГО МАТЕРИАЛА НА ОСНОВЕ АЛЮМИНИЕВОЙ МАТРИЦЫ АРМИРОВАННЫЙ СТАЛЬЮ ИЛИ БАЗАЛЬТОМ

The study objective is to evaluate the tribo-engineering properties of composite materials based on an aluminum matrix reinforced with steel or basalt in comparison with a material without reinforcement, and to develop a technology for obtaining such composite materials. Frames consisting of multidirectional fibers were used as reinforcing components: basalt wool (175-200 kg/m3 density); steel wool (4# class); melting temperatures of steel and basalt, which make up steel and basalt wool, are above 10000C, which makes it possible to pour aluminum without changing the aggregate state of reinforcing frames. The percentage of reinforcing components by weight is 4-5%. Deformable AB aluminum alloy was used as a matrix, which differs from the alloys of Al-Mg-Si system because of its higher level of tensile and yield strength. The composite materials under study were obtained by the liquid–phase method - casting according to melting models. Tribo-engineering properties were tested on a friction machine in the medium of Lukoil standard 10W40 SF/CC engine oil. To determine the anti-wear properties, tests were carried out for 1 hour, and to determine the antisize properties and the seizure load, tests were carried out with a constant increase in the load on the friction unit. The assessment of anti-wear and antisize properties was carried out by comparing the values of wear spots and seizure loads. It is found that the anti-wear properties increase by 76-85% when reinforcing samples with basalt wool and by 46-76% when reinforcing with steel wool in relation to an unreinforced sample. Antisize properties increase with basalt reinforcement by 23%, and decrease by 7% with steel reinforcement. Studies on assessing tribo-engineering properties of samples obtained by casting from AB aluminum alloy reinforced with basalt and steel have shown an improvement in anti-wear and antisize properties in relation to samples from AB alloy without reinforcement.

Doping Mg2+ to improve the Li+ diffusion rate and electrochemical performance of spinel LiMn2O4

In order to improve the normal temperature and high temperature cycling performance of spinel LiMn2O4, Mg2+-doped LiMn2-xMgxO4(0 ≤ x ≤ 0.1) cathode material was synthesized by the liquid phase method. XRD and EDS tests show that the doped Mg2+ successfully replaced part of Mn3+ into the lithium manganate cathode material lattice. After doping, the crystal structure is a spinel structure without impurity phase. Electrochemical performance tests show that different Mg2+ doping amount can effectively inhibit LiMn2O4 capacity attenuation during charging and discharging. The specific capacity of LiMn1.95Mg0.05O4 is 111.9 mAh/g at the current density of 0.2C at room temperature for the first discharge, the first discharge specific capacity of 1C was 110.06 mAh/g, and the discharge specific capacity was 105.79 mAh/g after 100 cycles, and the capacity retention rate is 96.12%. The specific capacity of the first discharge at a 0.2C current density at high temperature was 113.4 mAh/g, and after 100 cycles at 1C current density, the specific capacity is 99.29 mAh/g, and the capacity retention rate is 89.32%. The normal temperature and high temperature cycle performance of the sample is higher than that of the undoped Mg2+ sample.

In Situ Interfacial Engineering of CeO2/Bi2WO6 Heterojunction with Improved Photodegradation of Tetracycline and Organic Dyes: Mechanism Insight and Toxicity Assessment.

The construction of heterojunction photocatalysts is an auspicious approach for enhancing the photocatalytic performance of wastewater treatment. Here, a novel CeO2/Bi2WO6 heterojunction is synthesized using an in situ liquid-phase method. The optimal 15% CeO2/Bi2WO6 (CBW-15) is found to have the highest photocatalytic activity, achieving a degradation efficiency of 99.21% for tetracycline (TC), 98.43% for Rhodamine B (RhB), and 94.03% for methylene blue (MB). The TC removal rate remained at 95.38% even after five cycles. Through active species capture experiments, •O2 -, h+, and •OH are the main active substances for TC, RhB, and MB, respectively. The possible degradation pathways for TC are analyzed using liquid chromatography-mass spectrometry(LC-MS). The photoinduced charge transfer and possible degradation mechanisms are proposed through experimentation and density functional theory (DFT) calculations. Toxicity assessment experiments show a significant reduction in toxicity during the TC degradation process. This study uncovers the mechanism of photocatalytic degradation in CeO2/Bi2WO6 and provides new insights into toxicity assessment.

Mn5+-doped BaAl2O4, Ba3Al2O6, and Ba7Al2O10 phosphors emitting in the second near-infrared biological window

In recent years, NIR-II-type fluorophores with emission wavelengths within the 1000–1700 nm range have garnered widespread attention in the field of bioimaging due to their high tissue penetration ability. Here, Mn-doped BaAl2O4, Ba3Al2O6, and Ba7Al2O10 with NIR-II-type luminescence were synthesized by solid-phase or liquid-phase methods. Confirmed by XPS and EDS analysis, Mn is found uniformly distributed in the structure in the valence state of + 5. The optimal doping concentration of Mn5+ in the three matrices was analyzed by PLE and PL spectroscopy. In addition, the samples exhibit a wide excitation range spanning from 600 to 900 nm, coupled with a narrow emission band peaking between 1150 and 1200 nm. As both the excitation and emission wavelengths have excellent penetration capabilities in biological tissues, the synthesized fluorescent phosphors in this study hold potential for meaningful applications in the realm of fluorescence imaging.

Effect of multi-walled carbon nanotubes on the visible light photocatalytic activity of AgInS2 for Rhodamine B degradation

Visible-light responsive AgInS2 (AIS) nanoparticles modified with either pristine multi-walled carbon nanotubes (p-MWCNTs) or mixed-acid (H2SO4 and HNO3) oxidized multi-walled carbon nanotubes (o-MWCNTs) were synthesized using a low-temperature liquid phase method. The resulting nanocomposites are denoted as p-MWCNTs/AIS or o-MWCNTs/AIS. The structure, morphology, and optical properties of the samples were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), photoluminescence spectroscopy (PL), and ultraviolet-visible diffuse reflectance spectroscopy (UV–Vis DRS). The photocatalytic activity of p/o-MWCNTs/AIS towards the degradation of Rhodamine B (RhB) was investigated, and the optimal proportion of p/o-MWCNTs introduced on AIS was determined. A possible degradation mechanism of RhB over p/o-MWCNTs/AIS was proposed. The results demonstrated that p/o-MWCNTs were successfully incorporated into AIS, and the addition of an appropriate amount of p/o-MWCNTs improved the visible-light photocatalytic activity of AIS. Among the samples, 2 % o-MWCNTs/AIS exhibited the highest visible-light catalytic activity, achieving a degradation efficiency of 95 % within 40 min. The·⋅O2− species were identified as the main active species during the photocatalytic degradation process. The introduction of o-MWCNTs not only facilitated the separation of photogenerated electron-hole pairs (e−/h+) in AIS but also enhanced the visible-light absorption of AIS, leading to a significant improvement in its photocatalytic performance. Furthermore, the incorporation of o-MWCNTs greatly enhanced the cycling stability of AIS for reuse.

Efficient Fluoride Removal from Aqueous Solution Using Graphene/Ce Composite Supported on Activated Carbon

Background: More than 260 million people worldwide are affected by excess fluoride (F- &gt; 1.5 mg/L) in their drinking water. Fluorosis of the teeth and skeleton, among other health issues, is caused by it. Objective: The aim of this study is to evaluate the fluoride removal from contaminated water using graphene-based new adsorbent material. Method: Graphene (G) was prepared by a facile liquid-phase exfoliation method. CeO2 nanoparticles (NPs) were synthesized by the co-precipitation method. G was treated with CeO2 NPs in a probe sonicator to generate G/Ce material in solution. Finally, the impregnation evaporation process synthesized the G/Ce supported on activated carbon composite (G/Ce/AC). Results: FE-SEM analysis shows that the crumpling and scrolling sheets of G, the nanosized spherical shape of CeO2 NPs and a thick layer of nano-sized spherical particles has built up on the surface of graphene in G/Ce/AC composite. After conversion to G/Ce/AC Composite, the specific surface area of graphene was increased from 3.08 to 485.3621 m2/g. The adsorption of fluoride on G/Ce/AC was investigated using batch systems (effects of pH, contact time, adsorbent dosage and the initial fluoride concentration), adsorption isotherm and kinetic studies. The pseudo-second order was the one that best described the kinetic data, while the Langmuir isotherm best described the equilibrium data with a maximum adsorption capacity equal to 27.9 mg/g. Conclusion: Therefore, the results show that the G/Ce/AC composite was well synthesized and has excellent fluoride adsorption capacity compared to other materials already evaluated for this purpose.

Synthesis and Characterization of High-Purity, High-Entropy Diboride Ceramic Powders by a Liquid Phase Method

A nano-dual-phase powder with ultra-fine grain size was synthesized by the liquid precursor method at 1200 °C. A series of single-phase high-entropy ceramic powders ((Ti, Zr, Hf, Nb)B2, (Ti, Zr, Hf, Nb, Ta)B2, (Ti, Zr, Hf, Nb, Mo)B2, (Ti, Zr, Hf, Nb, Ta, Mo)B2) with high purity (C content less than 0.9 wt% and O content less than 0.7 wt%) and ultrafine (average grain sizes of 340–570 nm) were successfully synthesized at 1800 °C. The sample of (TiZrHfNbTa)B2 exhibited a hexagonal close-packed (HCP) structure, and the metal elements were uniformly distributed at the nanoscale, microscale, and macroscale. This method did not apply to the preparation of all high-entropy ceramic powders and was unfavorable for the formation of single-phase high-entropy borides when the size difference factor exceeded 3.9%. The present work provides a guide for the development of ceramic-based composites through precursor impregnation pyrolysis.

Air-Stable Ni Catalysts Prepared by Liquid-Phase Reduction Using Hydrosilanes for Reactions with Hydrogen.

The liquid-phase reduction method for the preparation of metal nanoparticles (NPs) by the reduction of metal salts or metal complexes in a solvent with a reducing agent is widely used to prepare Ni NPs that exhibit high catalytic activity in various organic transformations. Intensive research has been conducted on control of the morphology and size of Ni NPs by the addition of polymers and long-chain compounds as protective agents; however, these agents typically cause a decrease in catalytic activity. Here, we report on the preparation of Ni NPs using hydrosilane (Ni-Si) as a reducing agent and a size-controlling agent. The substituents on silicon can control not only the size but also the crystal phase of the Ni NPs. The prepared Ni NPs exhibited high catalytic performance for the hydrogenation of unsaturated compounds, aromatics, and heteroaromatics to give the corresponding hydrogenated products in high yields. The unique feature of Ni catalysts prepared by the hydrosilane-assisted method is that the catalysts can be handled under air as opposed to conventional Ni catalysts such as Raney Ni. Characterization studies indicated that the surface hydroxide was reduced under the catalytic reaction conditions with H2 at around 100 °C and with the assistance of organosilicon compounds deposited on the catalyst surface. The hydrosilane-assisted method presented here could be applied to the preparation of supported Ni catalysts (Ni-Si/support). The interaction between the Ni NPs and a metal oxide support enabled the direct amination of alcohols with ammonia to afford the primary amine selectively.

Phytic Acid-Promoted Exfoliation of Black Phosphorus Nanosheets for the Fabrication of Photothermal Antibacterial Coatings.

Medical device-associated infections (MDAI) caused by planktonic pathogens are of serious concern worldwide due to the emergence of drug resistance resulting from continuous overuse or misuse of antibiotics. Therefore, the design of non-antibiotics-based treatment for MDAI is of crucial importance. Black phosphorus (BP), a novel 2D material, has recently received much attention owing to its remarkable physical, chemical, mechanical, and functional features. However, the intricacy of the fabrication process has severely hampered the development of BP in prospective applications. In this study, a simple and eco-friendly liquid-phase exfoliation method of phytic acid (PA)-promoted exfoliation of BP nanosheets (PA@BP NSs) is developed for their potential application in antibacterial photothermal therapy. To impart the antimicrobial effects, the polydimethylsiloxane surfaces are functionalized with quaternized polymer (polyquaternium-2 or PQ) and PA@BP NSs, leading to the formation of PA-BP-PQ composite coatings. In addition to the contact-killing antibacterial effect of the cationic PQ, the PA-BP-PQ coating exhibits remarkable near-infrared irradiation-triggered bactericidal effects with low cytotoxicity both in vitro and in vivo. This study proposes a simple liquid-phase exfoliation technique for the fabrication of BP NSs and a one-step approach for the construction of PA-BP-PQ composite coatings for bi-modal (contact-killing and photothermal) antimicrobial therapy.

Fabrication of heterogeneous bimetallic nanochains through photochemical welding for promoting the electrocatalytic hydrogen evolution reaction

Heterogeneous bimetallic nanochains (NCs) have gained significant attention in the field of catalysis due to their abundant active sites, multi-component synergistic catalytic, and exotic electronic structures. Here, we present a novel approach to synthesize one-dimensional heterogeneous bimetallic nanochains using a local surface plasmon resonance (LSPR) based strategy of liquid-phase photochemical welding method containing self-assembly and subsequent welding processes. Initially, we introduce additives that facilitate the self-assembly and alignment of Au nanoparticles (NPs) into orderly lines. Subsequently, the LSPR effect of the Au NPs is stimulated by light, enabling the second metal precursor to overcome the energy barrier and undergo photodeposition in the gap between the arranged Au NPs, thereby connecting the nano-metal particles. This strategy can be extended to the photochemical welding of Au NPs-Ag and Au NRs. Using electrocatalytic hydrogen evolution reaction (HER) as a proof-of-concept application, the obtained one-dimensional structure of Au5Pt1 NCs exhibit promoted HER performances, where the mass activity of the Au5Pt1 nanochains is found to be 4.8 times higher than that of Au5Pt1 NPs and 10.4 times higher than that of commercial 20 wt% Pt/C catalysts. The promoted HER performance is benefited from the electron conduction ability and abundant active sites.

Enhanced anti-corrosive capability of waterborne epoxy coating by ATT exfoliated boron nitride nanosheets composite fillers

In this work, 2-amino-5 mercapto-1, 3, 4-thiadiazole/boron nitride nanosheets (ATT/BNNS) nanofillers were prepared via using ATT as intercalating agent to exfoliate BNNS by a liquid-phase assisted ultrasound method. The FTIR and the XPS consequences testify that the corrosion inhibitor ATT is successfully grafted onto BNNS. TEM results indicate that BNNS is adequately exfoliated by ATT and the agglomeration phenomenon is alleviated. BNNS, ATT and ATT/BNNS nanofillers were processed into the waterborne epoxy (WEP) respectively, and WEP composite coatings were then fabricated by a spraying method on the copper electrode. The EIS measurements demonstrate that WEP ATT/BNNS coating displays the best protective performance in combination with optical morphology observation under saline immersion, compared with other three coatings. It is mainly attributed to the combined action of active protection from ATT inhibitor and physical barrier from BNNS. The two-dimensional BNNS nanofiller dispersed in the WEP coating plays the role of physical barrier, forms a “labyrinth effect”, extends the invasion way of corrosive media, thus enhancing the physical barrier effect in the composite coating. Furthermore, ATT inhibitor can also diffuse through the coating to the copper substrate and build a safety shield to hold back further corrosion. Importantly, after 40 days immersion in 3.5 wt% NaCl solution, the value of impedance module at 0.01 Hz of WEP ATT/BNNS coating is about 2 orders of magnitude larger than that of pure WEP coating, revealing superior long-term anticorrosion performance.