Surface Molecular Structure Research Articles

Influence of ultraviolet aging on the structure, mechanical and gas permeability properties of hydrogenated nitrile butadiene rubber

AbstractThe effect of ultraviolet (UV) radiation on the structure and performance of hydrogenated nitrile butadiene rubber (HNBR) was studied in this paper. The HNBR was exposed to UV radiation for various durations (0, 7, 14, 21 and 28 days). The Fourier transform infrared spectroscopy (FTIR) results demonstrated that the surface molecular structures were oxidized to generate oxygenated species under UV radiation. The oxidative degree enhanced with the increase of aging time, resulting in thicker and denser cracks on the surface. The plausible aging mechanism of HNBR was suggested. The free volume of HNBR before and after UV aging was characterized by positron annihilation lifetime spectroscopy (PALS) and their cross‐linking density, compression set, mechanical and gas permeability properties were also analyzed. In the first 14 days of UV irradiation, the dominant chain‐scission reaction led to a decrease in cross‐linking density of HNBR, resulting in the enhancement of free volume and thereby the increase of gas permeability. When the aging time was longer than 14 days, cross‐linking reaction played a leading role and the free volume decreased, thus causing the reduction of gas permeability. As the aging time increased, the glass transition temperature (Tg), tensile strength and storage modulus of HNBR initially reduced and then increased, which was in agreement with the changing trend of cross‐linking density.

Fabrication of a novel nanocomposite electrode with ZnO-MoO3 and biochar derived from mushroom biomaterials for the detection of acetaminophen in the presence of DA

A novel two-dimensional ZnO-MoO3-C nanocomposite was synthesized by the green thermal calcination method with the biochar of mushroom derived carbon nanosheets and Zn1.5PMo12O40 polyoxometallate. The nanocomposite was used to modify a glassy carbon electrode (GCE) for the first time to construct an acetaminophen (AP) electrochemical biosensor. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and nitrogen adsorption/desorption isotherm (BET) results showed that the synthesized ZnO-MoO3-C nanocomposite has many layered nanostructure and a large surface area. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) indicated that ZnO-MoO3-C/GCE presented highly effective and accurate toward the oxidation of AP due to the stable molecular structure of the electrode surface. The DPV response of the proposed sensor exhibited selectively and sensitively determination for AP with a wider linear dependence on the concentration of AP from 2.5 to 2000 μM, and lower limits of detection (LOD) 1.14 μM, compared with other carbon-base material modified GCE and GCE electrodes. In addition, the proposed sensor was applied to detection of AP in real samples, and the recovery was the range from 94.7 to 101.0%, and RSD was less than 5%. It indicates that the proposed sensor has a hopeful capacity of extensive applications in bioanalysis and tablets.

Growth of Multilayers of Ionic Liquids on Au(111) Investigated by Atomic Force Microscopy in Ultrahigh Vacuum.

Understanding the growth of ultrathin films of ionic liquids (ILs) on metal surfaces is of highest relevance for a variety of applications. We present a detailed study of the growth of the wetting layer and successive multilayers of 1,3-dimethylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([C1C1Im][Tf2N]) on Au(111). By atomic force microscopy (AFM) in ultrahigh vacuum, we follow the temperature-dependent behavior between 110 and 300 K at defined coverages. We initially observe the formation of a wetting layer with a thickness of ∼0.37 nm with anions and cations arranged in a checkerboard structure. Stable AFM imaging up to 280 K allows us to follow the IL growing on top of the wetting layer in bilayers with an average thickness of ∼0.71 nm, that is, double the height of the wetting layer, in a bilayer-by-bilayer fashion. This growth behavior is independently confirmed from the surface morphology, as deduced from AFM and angle-resolved X-ray photoelectron spectroscopy. High-resolution AFM images at 110 K allow for identifying the molecular surface structure of the bilayers as a striped phase, which is one of the phases also seen for the wetting layer (Meusel, M.; Lexow, M.; Gezmis, A.; Schotz, S.; Wagner, M.; Bayer, A.; Maier, F.; Steinrück, H. P. Atomic Force and Scanning Tunneling Microscopy of Ordered Ionic Liquid Wetting Layers from 110 K up to Room Temperature. ACS Nano2020, 14, 9000–9010).

EDTAD-modified cassava stalks loaded with Fe3O4: highly efficient removal of Pb2+ and Zn2+ from aqueous solution.

In this study, a novel magnetic cassava stalk composite (M-EMCS) was prepared through modification with ethylenediamine tetraacetic anhydride (EDTAD) and loading of Fe3O4. The surface morphology, molecular structure, and magnetic characteristics of the composite were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), vibrating-sample magnetometer (VSM), and X-ray diffraction (XRD). It was shown that EDTAD and Fe3O4 were successfully modified and loaded in cassava straw (CS), respectively. The capacity of M-EMCS to absorb heavy metals under different influencing factors was tested by atomic absorption spectroscopy. The adsorption processes of both Pb2+ and Zn2+ were suitably described by second-order kinetic models and Langmuir models, indicating monolayer chemisorption. M-EMCS had high adsorption rates and adsorption capacities for these two metal ions. The adsorption of Pb2+ and Zn2+ reached a plateau after 10min, and the adsorption capacity of Pb2+ (163.93mg/g) was higher than that of Zn2+ (84.74mg/g). Thermodynamic analysis showed that the adsorption of two metals by M-EMCS was spontaneous, endothermic, and irreversible. XPS analysis showed that M-EMCS mainly removes Pb2+ and Zn2+ through ion exchange, chelation, and redox. Graphical abstract.

Crystal structure analysis of (E)‐N‐(3,5‐dimethylphenyl)‐2‐(substituted benzylidene)thiosemicarbazone: Experimental and theoretical studies

AbstractTwo novel thiosemicarbazone derivatives (E)‐N‐(3,5‐dimethylphenyl)‐2‐(3‐methylbenzylidene)thiosemicar‐bazone (1) and (E)‐N‐(3,5‐dimethylphenyl)‐2‐(3‐fluorobenzylidene)thiosemicarbazone (2) had been synthesized and characterized by FT‐IR, nuclear magnetic resonance, and elemental analysis. Single crystal X‐ray diffraction analysis showed that compound 1 belongs to triclinic system in P‐1 space group and compound 2 belongs to monoclinic system in C2/c space group. It could be seen from the determined crystal structure that the central skeleton NNHC(S)NH of both thiosemicarbazone compounds have good planarity. Density functional theory (DFT) calculations were done using B3LYP/6‐31+G(d, p) basis set and the calculated results are in good agreement with the experimental data. In addition, the UV‐visible absorption spectrum was estimated based on TD‐DFT quantum chemistry calculations. Likewise, the simulated absorption spectrum is very consistent with the experimental data. Combining Hirshfeld surface analysis and molecular structure, it was found that the intermolecular hydrogen bond NH···SC constitutes central symmetric dimer . Through quantum chemical calculation, we investigated the reduced density gradient function and the independent gradient model, which provided a deeper insight into the intermolecular and intramolecular interaction force of the compounds. The frontier molecular orbital analysis and molecular electrostatic potential were also discussed by theoretical calculations.

Surface modified nanoliposome formulations provide sustained release for 5-FU and increase cytotoxicity on A431 cell line

Malignant melanoma is a type of skin cancer with high risk of metastasis. 5-Fluorouracil is commonly used for treatment of skin cancer, however its penetration through the skin is found to be insufficient in some cases. Therefore, we optimized its pharmacokinetics by fabricating 5- Fluorouracil-loaded nanoliposome formulations modified with Poly-L-lysine coating. 5-Fluorouracil-loaded nanoliposome formulations were prepared using dipalmitoylphosphatidylcholine, dicethylphosphate and cholesterol having encapsulation efficiency of 45 ± 9.61%. The particle size, zeta potential, polydispersity index and encapsulation rate of the prepared formulation was found to be 237.9 ± 0.986 nm, 41.4 ± 1.060 mV, 0.233 ± 0.019 and 88.2 ± 7.85%, respectively. Surface characterization, molecular structure and thermal property illumination of the formulations were performed alongside stability studies. The In-vitro release of 5-FU from Lipo-FU6 and PLL-1 formulations was investigated by dialysis membrane method. Within the first 12 hours, the percentage release of 5-FU from Lipo-FU6 and PLL-1 formulations was observed to be 47.17% and 20.84%, respectively. Moreover, the cytotoxicity study on A431 epidermal carcinoma cell lines has revealed that 5-FU-loaded formulations were toxic to cells unlike the 5-FU free formulations. In conclusion, PLL coated nanoliposome formulations showed a potential to be an effective option for further combined drug/gene therapy applications.

Effects of iron precursor and loading on the catalytic performance of FeOx/CeO2 catalysts for NO reduction by CO

During the catalyst synthesis process, the precursor chosen could have great impact on the physiochemical and surface properties of the catalysts. More importantly, the precursor could result in very different catalytic activities of the catalyst. In this work, two series of FeOx/CeO2 catalysts were prepared using iron nitrate/sulfate precursors with a wide range of Fe loading (1 wt% – 30 wt%). The catalytic activity, physical property, surface morphology and surface/molecular structure were investigated using GC, BET, XRD, Raman, FT-IR as well as SEM and EDS techniques. From the results, although the physical properties (specific surface area, total pore volume) of the catalyst were similar with different precursors, the surface composition and molecular structures were very different. The iron nitrate precursor fully transformed into FeOx after the calcination process, whereas the iron sulfate precursor only partially transformed into FeOx, leaving some FeSO4 on the catalyst surface. The catalytic activity results suggested that a near monolayer coverage of FeOx on the catalyst surface was crucial to increase the catalytic activity in the NO reduction by CO reaction, while the presence of FeSO4 had advert impacts on the catalytic activity.

Regulating surface molecular structure of cellulose nanocrystals to optimize mechanical reinforcement effect on hydrophobic bio-based polyesters

The classical approach to prepare nanocomposites is often applied to chemical or physical modification of nanofillers to improve interfacial interaction between nanofillers and matrices. However, those methods might disturb the original reinforcement of nanoparticles due to the inhibition and even the absence of association among fillers. Here, we inspected a molecular design strategy using rod-like cellulose nanocrystals (CNCs) as fillers to study whether regulating the surface structure of CNC could allow a better reinforcement effect. Toward that, we prepared four modified CNCs by esterification with mono or binary anhydrides of different lengths of carbon chains. The long hydrocarbon chains were supposed to further improve the interfacial compatibility between CNC and poly(lactic acid) (PLA), and the terminal carboxyl groups should retain the association between nanoparticles. Results from transmittance of visible light for the nanocomposite films revealed homogeneous dispersion and good compatibility between modified nanocrystals and PLA matrix, especially for the long carbon-chain grafting CNCs. With an addition of 4 wt% dodecenyl succinic anhydride-modified CNC, the nanocomposite showed an increase in the tensile strength by ca. 170%. This was ascribed to the improved entanglement of grafting long chains and the potential interaction of terminal carboxyl groups on the CNC surface with the segments of PLA matrix, which enhanced association and compatibility between nanoparticles and matrix. This strategy prepared a biomass alloy of green materials reinforced by natural polymers and promoted the sustainable development of materials with high mechanical properties.

Investigation of mechanical, thermal and electrical parameters of gel combustion-derived cubic zirconia/epoxy resin composites for high-voltage insulation

Abstract The present study deals with the fabrication of epoxy composites reinforced with synthesized nano-zirconia, and to study their properties for high-voltage applications. The epoxy composites were extensively characterized to understand the morphology, mechanical, thermal, and electrical insulating behavior. The surface morphology and molecular structure of the nanoparticle and its interaction with the base matrix ware investigated by scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction (XRD). XRD profiles confirmed that particles were crystalline and nanosized. Moreover, the tensile characteristics were analyzed using various theoretical models that predict the stiffness of these composites. The glass transition temperature of the epoxy/ZrO2 composite increased with the increase in nanofiller content. The AC breakdown voltage reached a maximum of 14.8 kV for 2 wt% ZrO2 composite. The prepared composites have the potential to act as high-performance insulation materials.

Molecular beam epitaxy growth and surface structure of Sr1−xNdxCuO2 cuprate films

We report on the epitaxial growth and surface structure of infinite-layer cuprate Sr1-xNdxCuO2 films on SrTiO3(001) substrates by combining ozone-assisted molecular beam epitaxy and in situ scanning tunneling microscopy. Careful substrate temperature and flux control has been used to achieve single-phase, stoichiometric, and c-axis oriented films. The surface of the films is usually characterized by a mixed CuO2 surface and gridlike superstructure. The superstructure exhibits a periodicity of 3.47 nm that corresponds to a coincidence lattice between the overlayer peroxide SrO2 and underlying CuO2 plane, and gives rise to a conductance spectrum that is distinct from the Mott-Hubbard band structure of CuO2. At a higher Nd composition x > 0.1, a (2 x 2) surface characteristic of the hole-doped CuO2 emerges, which we ascribe to the intake of apical oxygens in the intervening Sr planes.

Plasma-Deposited Ru-Based Thin Films for Photoelectrochemical Water Splitting

Plasma-enhanced chemical vapor deposition (PECVD) was used to produce new Ru-based thin catalytic films. The surface molecular structure of the films was examined by X-ray photoelectron spectroscopy (XPS). To determine the electro- and photoelectrochemical properties, the oxygen evolution reaction (OER) process was investigated by linear sweep voltammetry (LSV) at pH = 13.6. It was found that Ru atoms were mainly in the metallic state (Ru0) in the as-deposited films, whereas after the electrochemical stabilization, higher oxidation states, mainly Ru+4 (RuO2), were formed. The stabilized films exhibited high catalytic activity in OER—for the electrochemical process, the onset and η10 overpotentials were approx. 220 and 350 mV, respectively, while for the photoelectrochemical process, the pure photocurrent density of about 160 mA/cm2 mg was achieved at 1.6 V (vs. reversible hydrogen electrode (RHE)). The plasma-deposited RuOX catalyst appears to be an interesting candidate for photoanode material for photoelectrochemical (PEC) water splitting.

Significantly Improved Surface Flashover Characteristics of Epoxy Resin/Al2O3 Nanocomposites in Air, Vacuum and SF6 by Gas-Phase Fluorination

In this work, epoxy resin incorporated with nano-Al2O3 of various concentrations, 0 wt.%, 1 wt.%, 3 wt.% and 5 wt.%, were prepared and subsequently fluorinated for 15 min, 30 min and 60 min at 40°C in a F2/N2 gas mixture (20/80 v/v) with pressure of 0.05 MPa. Fourier-transform infrared spectroscopy was employed for the chemical characterization of epoxy resin/Al2O3 nanocomposites which showed the molecular-chain scission during the gas-phase fluorination. Later, the effect of gas-phase fluorination on DC flashover characteristics of epoxy resin/Al2O3 nanocomposites was analyzed. It was found that gas-phase fluorination of pure epoxy resin can improve its DC flashover voltage in air and sulfur hexafluoride (SF6). In addition, nano-Al2O3 incorporation leads to a slight decrease of the DC flashover strength but it is still higher than that of non-fluorinated epoxy resin. This proves that suppression of charge accumulation can increase the DC flashover voltage of epoxy resin. The vacuum DC flashover voltage of epoxy resin/Al2O3 nanocomposites decreased by 35.8% after 30 min fluorination. However, the vacuum DC flashover voltage of epoxy resin incorporated with 1 wt.% nano-Al2O3 was 17.5% higher than that of unfilled epoxy resin. Based on the secondary electron emission avalanche model of vacuum flashover, the experimental results were analyzed. It was found that the fluorination modifies the surface molecular structure of epoxy resin/Al2O3 nanocomposites, which may weaken its adsorption capacity for gases and make it easier to desorb gases and reduce flashover voltage.

Effect of Molecular Structure of Quinones and Carbon Electrode Surfaces on the Interfacial Electron Transfer Process

Quinones can undergo thermodynamically reversible proton-coupled electron transfer reactions and are being applied as electroactive compounds in aqueous organic batteries. However, the electrochemi...

Density-functional tight-binding for phosphine-stabilized nanoscale gold clusters.

We report a parameterization of the second-order density-functional tight-binding (DFTB2) method for the quantum chemical simulation of phosphine-ligated nanoscale gold clusters, metalloids, and gold surfaces. Our parameterization extends the previously released DFTB2 “auorg” parameter set by connecting it to the electronic parameter of phosphorus in the “mio” parameter set. Although this connection could technically simply be accomplished by creating only the required additional Au–P repulsive potential, we found that the Au 6p and P 3d virtual atomic orbital energy levels exert a strong influence on the overall performance of the combined parameter set. Our optimized parameters are validated against density functional theory (DFT) geometries, ligand binding and cluster isomerization energies, ligand dissociation potential energy curves, and molecular orbital energies for relevant phosphine-ligated Aun clusters (n = 2–70), as well as selected experimental X-ray structures from the Cambridge Structural Database. In addition, we validate DFTB simulated far-IR spectra for several phosphine- and thiolate-ligated gold clusters against experimental and DFT spectra. The transferability of the parameter set is evaluated using DFT and DFTB potential energy surfaces resulting from the chemisorption of a PH3 molecule on the gold (111) surface. To demonstrate the potential of the DFTB method for quantum chemical simulations of metalloid gold clusters that are challenging for traditional DFT calculations, we report the predicted molecular geometry, electronic structure, ligand binding energy, and IR spectrum of Au108S24(PPh3)16.

Layer by layer exposure of subsurface defects and laser-induced damage mechanism of fused silica

Inert ion beams with large incident angle were used for layer by layer etching of chemical-mechanical polished fused silica. The evolution of the impurities, subsurface defects, surface roughness, and surface molecular structure after ion beam etching and their effects on the laser-induced damage threshold (LIDT) were investigated to understand the laser damage mechanism of fused silica. The impurity elements are mainly distributed at a depth of 0–200 nm of the sample surface, which will strongly absorb ultraviolet (UV) laser energy. The result is consistent with the measurement of weak photothermal absorption. After 500 nm removal of the fused silica surface, the deposition layer of polishing powder is removed, and the subsurface defects are exposed. Correspondingly, the amount and size of the defects reach the maximum, and result in the greastest surface roughness and deterioration of surface quality, which enhances the local optical field. As the removal depth increases, the passivation and removal of subsurface defects lead to a decrease in surface roughness and improvement of surface quality. In addition, the density of structural defects and the SiOSi bond angle will decrease after ion beam etching, which yields a densified and strengthened surface of fused silica. The results indicate that metallic impurities are the key factors that limit the improvement of LIDT. Moreover, subsurface defects restrict the further enhancement of LIDT. Therefore, ion beam etching can be developed to remove subsurface damage for improving the laser resistant capacity of fused silica.

Biphasic composite of calcium phosphate-based mesoporous silica as a novel bone drug delivery system

We reported the new biphasic composites of calcium phosphate and mesoporous silica material (CaP@MSi) in the form of powders and pellets as a potential bone drug delivery system for doxycycline hydrochloride (DOX). The CaP@MSi powders were synthesized by cationic surfactant-templating method. The effects of 10, 20, and 30% CaP content in the CaP@MSi powders on the molecular surface structure, the cytotoxicity against osteoblast cells in vitro, and the mineralization potential in simulated body fluid were investigated. The CaP@MSi characterized by the highest mineralization potential (30% CaP content) were used for DOX adsorption and pelletization process. The CaP which precipitated in the CaP@MSi composites was characterized as calcium-deficient with the Ca:P molar ratio between 1.0 and 1.2. The cytotoxicity assays demonstrated that the CaP content in MSi increases osteoblasts viability indicating the CaP@MSi (30% CaP content) as the most biocompatible. The combination of CaP and MSi was an effective strategy to improve the mineralization potential of parent material. Upon immersion in simulated body fluid, the CaP of composite converted into the bone-like apatite. The obtained pellets preserved the mineralization potential of CaP@MSi and provided the prolonged 5-day DOX release. The obtained biphasic CaP@MSi composites seem to have an application potential as bone-specific drug delivery system.

Leaching and purification of indium from waste liquid crystal display panel after hydrothermal pretreatment: Optimum conditions determination and kinetic analysis

Indium is one of the components with great recycling value in waste LCDs. Degradation of organic materials and the remain of indium in the solid phase can be simultaneously achieved by hydrothermal pretreatment via parameter regulation. Indium was transferred from the solid phase to the liquid phase by using sulfuric acid after hydrothermal pretreatment. Di-(2-ethylhexyl) phosphoric acid diluted by sulfonated kerosene and hydrochloric acid were used as extractant and stripping agent respectively to purify and concentrate indium from acidic leaching solution. The results indicated that the leaching yield of indium reached 100% under the optimal condition of reaction time of 40 min, reaction temperature of 70–80 °C, acid concentration of 0.5 M and solid-liquid (S/L) ratio of 1:2 g/mL. Given conditions of extraction time of 3 min at the organic phase to aqueous phase (O/A) ratio of 1:10 by 20% D2EHPA and stripping time of 10 min at the (O/A) ratio of 10:1 by 4 M HCl, the recovery efficiency of indium reached 97.25%. In addition, acid leaching process did not change the surface topography and molecular structure of glass substrate and had no negative effect on subsequent recycling of glass. The kinetic equation of leaching yield and reaction time at the temperature of 80 °C is 1 − (1 − y)1/3 = 0.0215 t. The reaction activation energy of metal indium leaching process is 50.64 kJ/mol.

One-pot synthesis of 3D Au nanoparticle clusters with tunable size and their application

In general, the preparation of Au nanoparticle clusters (NPCs) is more challenging than that of nanoparticles. The traditional multi-step method for preparing Au NPCs is time consuming and highly sensitive to the reaction conditions. Here, we report a simple and feasible method for the rapid preparation of Au NPCs (∼30 min), in which Au (III) is reduced to Au (0) by trisodium citrate, and assembled into NPCs in the presence of a trace amount of cysteine. The surface plasmon resonance peak of the Au NPCs is tunable and ranged from visible to near-IR regions by varying the content of cysteine added. The growth process of Au NPCs was monitored by dynamic light scattering, UV–vis absorption spectroscopy and transmission electron microscopy. Their elemental composition, chemical state and molecular structure of the sample surface were measured by x-ray photoelectron spectroscopy. The proposed synthesis mechanism has guiding significance for the preparation of other NPCs. Au NPCs used as surface-enhanced Raman spectroscopy substrate has a good enhancement effect because of its unique morphology.

Unraveling the role of surface molecular structure on vacuum flashover for fluorinated copolymers

To investigate the influence of surface molecular structure on the electrical performance of fluorinated copolymers, ultraviolet (UV) curable resin containing different types of fluorinated monomers (ethers and alkyls) were prepared by photopolymerization. The X-ray photoelectron spectra indicated the presence of fluorinated monomers on the surface after UV radiation. Furthermore, the surface morphology measurement revealed that these monomers cause a slight change to the surface roughness. Subsequently, the electrical properties were examined through a pulsed flashover test in vacuum. The results showed an improvement in the electrical strength of the specimen doped with dodecafluoroheptyl methacrylate (alkyls). In contrast, the sample doped with perfluoropolyether chains (ethers) exhibited no alleviation in flashover performance, despite the fact that its surface F 1s/C 1s atomic ratio is 10 times higher than that of the former. A coarse-grained model based on quantum chemical calculations reveals that electron traps are introduced at the surface because of the grafted fluorinated chains. Further explanation based on the free volume theory indicates that the higher gas absorption arising from the amorphous structure during the electron-induced degassing process accounts for the deterioration of the insulation system, which was verified by surface charge behavior before and after the flashover.

A highly sensitive sensor based on a computer-designed magnetic molecularly imprinted membrane for the determination of acetaminophen

In this paper, a sensor based on a magnetic surface molecularly imprinted membrane (MMIP) was prepared for the highly sensitive and selective determination of acetaminophen (AP). Before the experiment, the appropriate functional monomers and solvents required for the polymer were screened, and the molecular electrostatic potentials (MEPs) were calculated by the DFT/B3LYP/6-31 + G method. MMIP with high recognition of AP was synthesized based on Fe3O4@SiO2nanoparticles (NPs) with excellent core-shell structure. Next, a carbon paste electrode (CPE) was filled with a piece of neodymium-iron-boron magnet to make magnetic electrode (MCPE), and MMIP/MCPE sensor was obtained by attaching a printed polymer to the surface of the electrode under the strong magnetic. Due to the stable molecular structure of the electrode surface, the sensor is highly effective and accurate for detection of AP using DPV. The DPV response of the sensor exhibited a linear dependence on the concentration of AP from 6 × 10−8 to 5 × 10−5 mol L−1 and 5 × 10−5 to 2 × 10−4 mol L−1, with a detection limit based on the lower linear range of 1.73 × 10−8 mol L−1(S/N = 3). When used for determination of AP in actual samples, the recovery of the sensor to the sample was 95.80–103.76%, and the RSD was 0.78%–3.05%.