查找使用阿拉丁产品的科研文献

Robust Plasmonic Structures Fabricated by Femtosecond Laser-Assisted Anisotropic Intaglio Engraving on Quartz for High-Sensitivity Surface Plasmon Resonance Sensing

Yibo Lu,Lan Jiang,Mengmeng Wang,Xin Li,Sumei Wang,Xueqiang Zhang,Bo Chen,Xiaorui Li,Chang Lu

Fabrication of plasmonic structures on a gold film is a well-established approach to improve the performance of surface plasmon resonance (SPR) sensors. However, traditional fabrication techniques, such as photolithography, electron beam lithography (EBL), and focused ion beam (FIB) milling, often involve complex procedures and costly equipment. In this study, we present a mask-free, convenient method to fabricate robust plasmonic structures on the surface of z-cut α-quartz by combining femtosecond laser-induced modification with chemical etching for high-sensitivity Kretschmann configuration SPR sensing. We find that the etching process of laser-modified α-quartz in ammonium bifluoride (NH4HF2) solution proceeds in two distinct stages: isotropic etching and anisotropic etching. By comparing the etching morphology of the craters ablated by femtosecond laser with wavelengths of 400 and 800 nm, we observe that due to the lower threshold fluence and steeper crater profile, the 400 nm laser can induce more pronounced anisotropic etching, leading to sharper inverted pyramid structures. A 5-nm-thick Cr film and a 50-nm-thick Au film are then deposited on the patterned quartz surface, which is used to detect the refractive indices (RIs) of glycerol solutions as an SPR sensor. The inverted pyramid structures can enhance the localized electric fields, causing a red shift of the resonance peak and thereby improving the sensitivity of the SPR sensor. The sensor demonstrates a sensitivity of 4662.21 nm/RIU, achieving a 21.51% improvement compared with a traditional SPR sensor with a plain Au film under the same light incident angle. The refractive index (RI) resolution reaches 2.7 × 10–5 RIU, and the figure of merit (FOM) is 85.36 RIU–1. Femtosecond laser-assisted chemical etching offers an efficient and convenient method for fabricating plasmonic structures on α-quartz. The high-sensitivity SPR sensors developed through this approach demonstrate promising potential for applications in fields such as medical diagnostics, disease detection, and environmental monitoring.

Impact of Molecular Structure on Secondary Organic Aerosol Formation from Aliphatic Carbonyls

Chengrui Liang,Shuxiao Wang,Bin Zhao,Boyang Feng,Qipeng Qu,Liang Zhu,Jiming Hao

Aliphatic carbonyls widely exist in source emissions and the atmosphere, serving as secondary organic aerosol (SOA) precursors. Molecular structure including carbon number and functional groups influences SOA formation. However, limited research was conducted on the vastly different SOA yields among aliphatic carbonyls, and the impact of the molecular structure remains unclear and controversial. In this study, 11 aliphatic carbonyls were photooxidized to study the SOA formation and gas-phase products in an oxidation flow reactor (OFR). The maximum SOA yields of C15 and C13 straight-chain carbonyls are 0.41–0.52 and 0.18–0.23, lower but within a comparable range with long-chain alkanes, whereas those for C8–C10 carbonyls are less than 0.04. Aliphatic carbonyls with more carbon have significantly higher SOA yields, accompanied by additional multigenerational products. The SOA yield of n-aldehyde is moderately higher than that of n-alkan-2-one with the same carbon number, due to the enhanced formation of long-chain acids with lower volatility than dicarbonyls. The saturated cyclic structure increases the SOA yield by forming more multifunctional products with additional aldehyde groups upon ring-opening, whereas the branched structure easily fragmented and decreased the SOA yield. This study highlights that the aliphatic carbonyls with more carbon numbers and a cyclic structure with less branching may have higher SOA yields.

Dual Dynamic Supramolecular Interaction-Enhanced All-Solid-State Electrolyte for High-Performance Lithium Metal Batteries

Xue Wang,Yaohan Chen,Nannan Zhang,Xinrui Chai,Zejin Yu,Xiaofeng Li,Shenghai Li

Poly(ethylene oxide) (PEO)-based polymer electrolytes exhibit great potential for application in all-solid-state batteries. However, the insufficient Li+ transport efficiency has hindered the large-scale development of PEO. To address these challenges, we introduced a dual supramolecular interaction strategy for the preparation of PEO-based electrolytes, where tetrafluoroterephthalonitrile (TFTPN) complexes with Li+ and phenylenediboronic acid (PBA) as anion capturer were engaged. Through the synergistic effects of Lewis acid–base interactions between TFTPN and Li+, and hydrogen bonding-derived anchoring for bis(trifluoromethylsulfonyl)imide (TFSI–) anion by boronic acid moieties in PBA, the Li+ transport efficiency was significantly enhanced with ionic conductivity of 6.14 × 10–4 S cm–1 and Li+ transference number of 0.6 at 50 °C (1.01 × 10–4 S cm–1 at 25 °C). PEO-TFTPN-PBA-based cell enabled a maximum discharge specific capacity of 130.7 mAh g–1 at 2 C, and a high retention rate of 81.7% after 200 cycles. This study will provide an effective approach and a synergistic material design strategy for leveraging dynamic supramolecular interactions within PEO-based solid polymer electrolytes.

La3Pd2NaO9: A High-Valent Insulating Palladate

Qingqing Yang,Ning Guo,Tieyan Chang,Zheng Guo,Xiaoli Wang,Chuanyan Fan,Chao Liu,Lu Han,Feiyu Li,Tao He,Qiang Zheng,Yu-Sheng Chen,Junjie Zhang

A high-valent palladate, La3Pd2NaO9, has been synthesized for the first time. Single crystals with dimensions of 20 μm on the edge were successfully grown using the flux method at 420 °C and 70 bar oxygen pressure. Energy dispersive spectroscopy (EDS) and inductively coupled plasma mass spectroscopy (ICP) measurements show that the atomic ratio of La: (Pd + Na) is 3:3 and Pd: Na is 2:1. X-ray photoelectron spectroscopy (XPS) measurements show that the oxidation state of Pd is dominated by the +4. Synchrotron X-ray single-crystal diffraction measurements revealed that this material crystallizes in the monoclinic P21/c space group with charge ordering of Na and Pd. Real-space imaging via scanning transmission electron microscopy (STEM) confirmed the crystal structure and revealed excellent sample homogeneity. Electrical resistivity measurements show an insulating behavior. Magnetic measurements show an unexpected paramagnetic behavior, which probably originates from a small fraction of high-spin Pd2+ evidenced by XPS. The successful growth of La3Pd2NaO9 single crystals with a high-valent oxidation state of Pd offers an approach for exploring interesting palladates, including potential bilayer Ruddlesden–Popper palladates analogous to the high temperature superconducting La3Ni2O7.

Reproducible Plasmonic Nanopyramid Array of Various Metals for Highly Sensitive Refractometric and Surface-Enhanced Raman Biosensing

Li Zhang,Xuemeng Li,Yangyang Wang,Kang Sun,Xuexian Chen,Huanjun Chen,Jianhua Zhou

Localized surface plasmon resonance (LSPR) biosensors show great potential for practical/commercial use in clinical diagnosis, home healthcare, environmental analysis, and public healthcare. However, two main issues, that is, low refractometric sensitivity and low reproducibility (large-area uniformity and batch-to-batch consistency), hinder the extensive applications of LSPR biosensors. Therefore, plasmonic nanostructures with high sensitivity and excellent reproducibility are desirable for preparing reliable LSPR sensors. Herein, we have fabricated plasmonic nanopyramid arrays (NPAs) for several batches with reproducible morphology and optical properties by elastic soft lithography and metal thermal evaporation. NPAs of various metals (i.e., Al, Au, and Ag) were also prepared by thermal evaporation with the according metals. The transmission spectra of these NPAs showed several narrow LSPR peaks in the visible-infrared wavelength region. The refractometric sensitivities of the LSPR peaks were systematically studied, and high refractometric sensitivities of 774.0, 472.8, and 421.0 nm/RIU were achieved on Al, Au, and Ag NPAs, respectively. To demonstrate the potential of the NPAs for multiplex applications, we first applied this highly sensitive Al NPA biosensor to monitoring the process of proliferation of HeLa cancer cells, in situ and in real time. Then, we demonstrated that the Au NPA was able to identify the absorbed analytes on its surface through the surface-enhanced Raman scattering spectrum. In addition, the finite difference time domain simulations were performed to reveal the electromagnetic field enhancement on NPAs. Because of the properties of high sensitivity and excellent reproducibility of the metal NPA LSPR substrates, as well as the simplicity and cost efficiency of the fabrication method, our proposed work will accelerate the practical use of LSPR sensors.

Multifunctional Up-Converting Nanocomposites with Smart Polymer Brushes Gated Mesopores for Cell Imaging and Thermo/pH Dual-Responsive Drug Controlled Release

Xiao Zhang,Piaoping Yang,Yunlu Dai,Ping'an Ma,Xuejiao Li,Ziyong Cheng,Zhiyao Hou,Xiaojiao Kang,Chunxia Li,Jun Lin

Multifunctional nanocarriers based on the up-conversion luminescent nanoparticles of NaYF 4 :Yb 3+ /Er 3+ core (UCNPs) and thermo/pH-coupling sensitive polymer poly[( N -isopropylacrylamide)- co -(methacrylic acid)] (P(NIPAm- co -MAA)) gated mesoporous silica shell are reported for cancer theranostics, including fluorescence imaging, and for controlled drug release for therapy. The as-synthesized hybrid nanospheres UCNPs@mSiO 2 -P(NIPAm- co -MAA) show bright green up-conversion fluorescence under 980 nm laser excitation and the thermo/pH-sensitive polymer is active as a “valve” to moderate the diffusion of the embedded drugs in-and-out of the pore channels of the silica container. The anticancer drug doxorubicin hydrochloride (DOX) can be absorbed into UCNPs@mSiO 2 -P(NIPAm- co -MAA) nanospheres and the composite drug delivery system (DDS) shows a low level of leakage at low temperature/high pH values but significantly enhanced release at higher temperature/lower pH values, exhibiting an apparent thermo/pH controlled “on-off” drug release pattern. The as-prepared UCNPs@mSiO 2 -P(NIPAm- co -MAA) hybrid nanospheres can be used as bioimaging agents and biomonitors to track the extent of drug release. The reported multifunctional nanocarriers represent a novel and versatile class of platform for simultaneous imaging and stimuli-responsive controlled drug delivery.

Rational design of MIL-88A(Fe)/Bi2WO6 heterojunctions as an efficient photocatalyst for organic pollutant degradation under visible light irradiation

Qianwen Li,Limei Li,Xuanyu Long,Yu Tu,Lanqing Ling,Jiabao Gu,Liwei Hou,Yi Xu,Nan Liu,Zequan Li

Photocatalysis provides an exciting way to directly utilize solar energy to degrade environmental pollution. This process, however, suffers from rapid recombination of the photogenerated charges leading to low efficiency and instability. Herein, we report a novel MIL-88A(Fe)/Bi 2 WO 6 heterojunction as a highly efficient photocatalyst for degradation of organic compounds under visible-light irradiation. When tested in 10 mg/L Rhodamine B (RhB), such catalyst can get remarkable degradation efficiency, up to 96%, at 50 min visible-light irradiation time. Significantly, it also shows super performance for Tetracycline (TC). Moreover, MIL-88A(Fe)/Bi 2 WO 6 exhibited excellent photostability and recyclability. The superior photocatalytic activity of MIL-88A(Fe)/Bi 2 WO 6 may be the formation of a heterojunction between MIL-88A(Fe) and Bi 2 WO 6 with high surface area, which provides abundant active sites to drastically promote interactions between photocatalyst and reactants. Furthermore, the related electrochemical analysis and free radicals trapping experiments indicated that both •O 2 − and h + have significant effect in the degradation process. Our findings of the work not only provide a novel insight to the design and develop MOF-based heterojunction photocatalysts but also suggest its great potential application value for environmental remediation.

Direct synthesis of substrate-independent nanoparticles for antibacterial application

Wei Ye,Nan Wang,Lingren Wang,Sen Liu,Chao Zhang,Jingjing Liu,Jiang Xin,Hongyan Ding

In the present study, we designed a substrate-independent antimicrobial nanoparticle (SNP) via self-assembly of poly (acrylic acid) (PAA) and poly (diallyl dimethyl ammonium chloride) (PDDA). The prepared nanoparticle, with a cube structure, as revealed by scanning electron microscope (SEM), maintained structural integrity even after extensive washing. In addition, the SNP was endowed with substrate-independent adhesive affinity to various surfaces by carbodiimide reaction owing to the carboxyl group of PAA. The results of blood compatibility and cytocompatibility demonstrated that the SNP had a limited effect on blood coagulation and cell proliferation. The results of antibacterial tests indicated that the SNP exhibited significant inhibition ability for both gram-negative and gram-positive bacteria, reducing cell amount by 97.2% and 98.2% within 24 h for Escherichia coli and Staphylococcus aureus, respectively. The hemocompatibility and cytocompatibility were attributed to the introduction of carboxyl group, and the significantly antimicrobial property was ascribed to the introduction of PDDA. Furthermore, the SNP maintained outstanding long-term antimicrobial property. In general, it was believed that the designed SNP probably showed potential for applications in various biological and clinical fields.

Relationships between structures of surfactants and their anti-hygroscopicity performance of ammonium nitrate particles

Baha I. Elzaki,Zhang Yue Jun

The coating processing condition was used for the research of coating ammonium nitrate particles by means of the surfactants as coating materials which have the same polar heads with different non-polar straight hydrocarbon tails or the same non-polar straight hydrocarbon tails with different polar heads, in order to investigate the relationships between structures of surfactants and their anti-hygroscopicity used in ammonium nitrate particles coated. Furthermore, the relationships and possibly mechanism were analyzed and discussed based on both the experimental results and the selected coating processing, basic property of materials and behaviors of material in coating processes. The experimental results indicated that, the anti-hygroscopicity performance of C 16 -alchol and C 18 -acid were best ones within the all groups of selected surfactants with polar heads. The best declines of hygroscopicity of ammonium nitrate particles coated were 29.26% for C 16 -alcohol and 24.0% for C 18 -acid. And for the later, the anti-hygroscopicity performance of C 18 -acid and C 20 -acid were best ones within the all groups of selected surfactants with longer tails, and that of C 16 -alcohol and C 14 -amine were best ones with shorter tails, their best declines were 24.0%, 20.39%, 29.26% and 18.6%, respectively. The mechanism analysis results indicated that the decline of hygroscopicity were influenced by both the coating processing condition and the material properties, such as the polarity, hydroscopicity, solublity in solves and especially the surfactivity of the used surfactants, and the later, i.e. the material properties would play an important role when the processing condition and solvent used in coating ammonium nitrate particles were fixed. Therfore, the property of coating materials which are depending on their structures and the bahaviours of coating material molecules in coating processes dominated commonly and ultimatly anti-hydroscopicity of coated ammonium nitrate particles, under a selected coating processing condition. This work provides new insights on understanding the relationship between structure of surfactants and anti-hygroscopicity performance to further improve the anti-hygroscopicity performance of ammonium nitrate particles.

Studies of the plasticizing effect of different hydrophilic inorganic salts on starch/poly (vinyl alcohol) films

Xiancai Jiang,Hongmei Li,Yong Luo,Yulai Zhao,Linxi Hou

The effects of different inorganic salts LiCl, MgCl 2 ·6H 2 O, CaCl 2 , and AlCl 3 ·6H 2 O on the crystalline, thermal, water vapor barrier, and tensile properties of starch/PVA films were studied. The high plasticizing efficiency of all these four inorganic salts for starch/PVA film was confirmed by the obtained results. These four salts all had a good compatibility with starch/PVA within the content of 15 wt% and starch/PVA became completely miscible with the addition of 15 wt% inorganic salts. All these four salts had a strong destroying effect on the crystals of starch and PVA. Among these four salts, AlCl 3 ·6H 2 O had the largest negative effect on the thermal stability of starch/PVA and LiCl had the largest improving effect on the water sorption rate of starch/PVA film. On the whole MgCl 2 ·6H 2 O and CaCl 2 were the more suitable plasticizer for starch/PVA film among these four inorganic salts. With the addition of 15 wt% MgCl 2 ·6H 2 O and CaCl 2 , the elongation at break of starch/PVA film could reach to 418.83% and 434.80%, respectively.

Simultaneous degradation of p-nitrophenol and reduction of Cr(VI) in one step using microwave atmospheric pressure plasma

Chaoxia Zhao,Li Xue,Hongxiao Shi,Wenqi Chen,Yu Zhong,Yi Zhang,Yanping Zhou,Kama Huang

Different physicochemical properties between Cr(VI) and phenolic compounds pose serious challenges for the effective treatment of co-contamination. This study developed an electrodeless high-flow microwave atmospheric plasma jet for the single-step simultaneous degradation of p -nitrophenol (PNP) and reduction of Cr(VI). Following a 15 min treatment with microwave atmospheric pressure plasma, the removal efficiency of Cr(VI) and PNP reached 97.5% and 93.6%, respectively, whereas that of total organic carbon reached 30.2%. Adding PNP to the solution significantly improved Cr(VI) reduction, whereas PNP degradation increased slightly with Cr(VI). The results indicate that the PNP intermediates significantly affected Cr(VI) reduction. Additionally, long-lived H 2 O 2 and short-lived · H aided the reduction of Cr(VI) during plasma treatment. The addition of hydroxyl scavengers during treatment implied that · O H was largely responsible for PNP oxidation. High-performance liquid chromatography–mass spectroscopy (HPLC-MS) revealed that PNP intermediates, including p -nitrocatechol and 5-nitrobenzene-1,2,3-triol, function as Cr(VI) reductants. On the basis of the examined intermediate products, the potential PNP degradation pathway was investigated. The factors that could influence simultaneous dehgradation and reduction, including solution pH, gas velocity, and distance between the plasma outlet and the water surface were researched. Low pH supports Cr(VI) reduction, and the promotion of PNP for Cr(VI) reduction applies to all pH values. The degradation of PNP is insensitive to pH values with or without Cr(VI). The optimal gas velocity for PNP degradation and Cr(VI) reduction was revealed to be 6 L/min. The simultaneous removal of PNP and Cr(VI) benefits from a shorter distance between the plasma outlet and the water's surface.

Preparation and self-assembly properties of surface active hydrophobically associating polyacrylamide

GaoShen Su,Yue Luo,Fan Li,Xiaorong Yu