Close-packed Arrays Research Articles

Interaction of obliquely incident lasers with anharmonic CNTs acting as dipole antenna to generate resonant THz radiation

The present paper explores the terahertz (THz) generation by the interaction of obliquely incident laser beams with the array of vertically aligned anharmonic carbon nanotubes (CNTs) acting as dipole antennas. In the scheme, anharmonicity arises due to the nonlinear variation of restoration force on the various electrons of CNTs and it plays a key role in the enhancement of THz generation. The anharmonic CNTs help in broadening the resonance peak, which paves the way for the enhancement of the normalized THz amplitude. The laser beams incident obliquely on the close-packed array of vertically aligned anharmonic CNTs grown over the glass substrate and set oscillations in the CNTs so that each CNT act as the oscillatory dipole to generate THz radiation. The THz electric field shows enhancement at surface plasmon resonance frequency , where is the characteristic parameter of CNTs, is the relative permittivity of lattice and is the plasma frequency. This scheme is quite suitable to generate THz radiations in the milliwatt range of optimized values of the laser and CNTs parameters. We also explore the impact of polarization, S-parameter, critical angle, and length-matching effects of CNT antennas on the THz generation.

Quasi-periodic micro-lens array via laser-assisted wet etching

A close-packed micro-lens array (MLA) is widely used not only in novel optical systems but also in various engineering fields, such as semiconductors and display devices. In this paper, we present a simple and efficient method for fabricating MLAs on a glass substrate via laser ablation with a single femtosecond laser pulse and chemical wet etching in a hydrofluoric acid solution. The shapes of concave micro-lenses were optimized for laser pulse energy and etching time, and ∼70 000 micro-lenses with 15 µm diameter were formed. The shape of the micro-lens varies significantly with respect to the etching time in accordance with an initial ablated area (or laser energy), which is a key feature in fabricating micro-lenses of several tens of μm. Using the glass MLA as a mold, a polydimethylsiloxane convex-plano lens array was replicated, and the performance of the optical imaging and beam integrator was then examined.

Structure of a cholinergic cell membrane.

Cell membranes are complex assemblies of proteins and lipids making transient or long-term associations that have yet to be characterized at a molecular level. Here, cryo-electron microscopy is applied to determine how phospholipids and cholesterol arrange between neighboring proteins (nicotinic acetylcholine receptors) of Torpedo cholinergic membrane. The lipids exhibit distinct properties in the two leaflets of the bilayer, influenced by the protein surfaces and by differences in cholesterol concentration. In the outer leaflet, the lipids show no consistent motif away from the protein surfaces, in keeping with their assumed fluidity. In the inner leaflet, where the cholesterol concentration is higher, the lipids organize into extensive close-packed linear arrays. These arrays are built from the sterol groups of cholesterol and the initial saturated portions of the phospholipid hydrocarbon chains. Together, they create an ordered ∼7 Å-thick "skin" within the hydrophobic core of the bilayer. The packing of lipids in the arrays appears to bear a close relationship to the linear cholesterol arrays that form crystalline monolayers at the air-water interface.

(Invited) Enabling Fast Charging of Lithium-Ion Batteries without Lithium Plating

Today’s Li-ion technology is highly optimized for performance at relatively slow charging operation. However, significant challenges still present for fast charging conditions (> 4C). In state-of-the-art Li-ion batteries (LIBs) with high energy densities, the electrodes are relatively thick (> 100 μm), which leads to a tradeoff between energy density and high-power performance. In addition, the electrochemical potential of the anode can easily become more negative than Li/Li+ during fast charging, resulting in Li plating [1]. Therefore, new approaches are needed to overcome these energy/power tradeoffs in LIBsIn this talk, I will introduce three strategies to enable fast charging LIBs, using industrially-relevant pouch cells with thick (>3 mAh/cm2) electrode loadings. In the first strategy, vertical channels are introduced into post-calendared electrodes using laser ablation patterning [2]. The resulting 3-D anode architecture consists of a hexagonal close-packed array of vertical channels that serve as linear pathways for rapid ionic diffusion through the electrode thickness. This allows for a more homogeneous flux of Li throughout the volume of the electrode. As a result, the accessible capacity of the electrode during fast charging increases, and Li plating is eliminated.In the second strategy, the energy/power tradeoffs in carbonaceous anode materials are overcome by forming hybrid blends of graphite and hard carbon [3]. This allows for a balance between the higher energy density of graphite with the faster rate performance of hard carbon. By controlling the graphite/hard carbon ratio, we identify an optimal blend for fast charging.In the third strategy, we demonstrate the potential to eliminate Li plating and enabling 4C fast charging purely through interfacial control. This is achieved by coating the surface of graphite with a solid-state electrolyte material using Atomic Layer Deposition (ALD) [4]. These coatings eliminate electrolyte decomposition during the formation cycle, resulting in an “artificial SEI” with a resistance that is 75% lower than the natural SEI that forms in carbonate electrolytes. This challenges the fundamental assumption that fast charging of thick graphite anodes must be solved by improving mass transport, highlighting the critical role of the SEI on fast-charge performance.[1] Y. Chen, K.-H. Chen, A. J. Sanchez, E. Kazyak, V. Goel, Y. Gorlin, J. Christensen, K. Thornton, N. P. Dasgupta, J. Mater Chem. A 9, 23522 (2021).[2] K.-H. Chen, M. Namkoong, V. Goel, C. Yang, S. Kazemiabnavi, S. M. Mortuza, E. Kazyak, J. Mazumder, K. Thornton, J. Sakamoto, N. P. Dasgupta, J. Power Sources 471, 228475 (2020).[3] K.-H. Chen, V. Goel, M. J. Namkoong, M. Wied, S. Müller, V. Wood, J. Sakamoto, K. Thornton, N. P. Dasgupta, Adv. Energy Mater. 11, 2003336 (2020).[4] E. Kazyak, K.-H. Chen, Y. Chen, T. H. Cho, N. P. Dasgupta, Adv. Energy Mater, In Press (2021).

A Bayesian approach to high fidelity interferometric calibration − II: demonstration with simulated data

ABSTRACT In a companion paper, we presented bayescal, a mathematical formalism for mitigating sky-model incompleteness in interferometric calibration. In this paper, we demonstrate the use of bayescal to calibrate the degenerate gain parameters of full-Stokes simulated observations with a HERA-like hexagonal close-packed redundant array, for three assumed levels of completeness of the a priori known component of the calibration sky model. We compare the bayescal calibration solutions to those recovered by calibrating the degenerate gain parameters with only the a priori known component of the calibration sky model both with and without imposing physically motivated priors on the gain amplitude solutions and for two choices of baseline length range over which to calibrate. We find that bayescal provides calibration solutions with up to 4 orders of magnitude lower power in spurious gain amplitude fluctuations than the calibration solutions derived for the same data set with the alternate approaches, and between ∼107 and ∼1010 times smaller than in the mean degenerate gain amplitude, on the full range of spectral scales accessible in the data. Additionally, we find that in the scenarios modelled only bayescal has sufficiently high fidelity calibration solutions for unbiased recovery of the 21-cm power spectrum on large spectral scales (k∥ ≲ 0.15 hMpc−1). In all other cases, in the completeness regimes studied, those scales are contaminated.

Easy-to-Operate Co-Flow Step Emulsification Device for High-Throughput Three-Dimensional Cell Culture.

Cell culture plays an essential role in tissue engineering and high-throughput drug screening. Compared with two-dimensional (2D) in vitro culture, three-dimensional (3D) in vitro culture can mimic cells in vivo more accurately, including complex cellular organizations, heterogeneity, and cell–extracellular matrix (ECM) interactions. This article presents a droplet-based microfluidic chip that integrates cell distribution, 3D in vitro cell culture, and in situ cell monitoring in a single device. Using the microfluidic “co-flow step emulsification” approach, we have successfully prepared close-packed droplet arrays with an ultra-high-volume fraction (72%) which can prevent cells from adhering to the chip surface so as to achieve a 3D cell culture and make scalable and high-throughput cell culture possible. The proposed device could produce droplets from 55.29 ± 1.52 to 95.64 ± 3.35 μm, enabling the diverse encapsulation of cells of different sizes and quantities. Furthermore, the cost for each microfluidic CFSE chip is approximately USD 3, making it a low-cost approach for 3D cell culture. The proposed device is successfully applied in the 3D culture of saccharomyces cerevisiae cells with an occurrence rate for proliferation of 80.34 ± 3.77%. With low-cost, easy-to-operate, high-throughput, and miniaturization characteristics, the proposed device meets the requirements for 3D in vitro cell culture and is expected to be applied in biological fields such as drug toxicology and pharmacokinetics.

Improved performance in microsphere-assisted 2D and 3D imaging by polystyrene microspheres semi-immersed in SU-8 resist

In this work, we introduce a method to improve the performance of microsphere-assisted imaging by optimizing the refractive index of immersion media. In the method, polystyrene (PS) microspheres are semi-immersed in water, spin-on-glass, SU-8 resist, and S1805 resist. We experimentally find that the distortion of the image observed by a PS microsphere semi-immersed in SU-8 resist is the smallest while the resolution of the semi-immersed microsphere is the highest. ZEMAX software simulations show that PS microspheres semi-immersed in SU-8 resist have the smallest distortion and spherical aberration. Moreover, numerical simulations also reveal that they have the strongest peak intensity, the narrowest waist, and the shortest focal length of the photonic nanojet. When the semi-immersed PS microsphere is used in microsphere-assisted microscopy, a 200-nm-diameter hexagonally close-packed (hcp) silica nanoparticle array can be clearly distinguished. When they are used in microsphere-assisted interference microscopy, a 250-nm-diameter hcp silica nanoparticle array can be resolved.

Transducer design for low-frequency circular close-packed array and its mutual radiation analysis.

Conventional flextensional transducers possess advantages of low frequency, small dimension, and high power [K. D. Rolt, J. Acoust. Soc. Am. 87, 1340 (1990)]. The low-frequency circular array composed of flextensional transducers has a strong mutual radiation effect due to the large vibration amplitude of the radiation surface located inside the circular array and the close distance between array elements [Z. Y. He et al., AIP Conf. Proc. 1272, 345 (2010)]. Here, a single-sided radiation flextensional transducer (SSR FT) is designed for a low-frequency circular close-packed array to diminish the mutual radiation effect. On the basis of the vibration principle of SSR FT, effects of structural parameters on electroacoustic, vibration, and radiation performance are studied for the final design of the transducer. Subsequently, the mutual radiation effect of circular close-packed arrays composed of SSR FTs and their counterparts is qualitatively analyzed on the basis of resonant mass, equivalent circuit, and numerical simulations. Finally, fabricated and tested circular arrays lead to a conclusion that the circular array composed of SSR FTs has a weaker mutual radiation effect and smaller dimensions than its counterpart composed of class IV FTs [K. P. B. Moosad, G. Chandrashekar, M. J. Joseph, and R. John, Appl. Acoust. 72, 127-131 (2011)]. The results confirm that the circular close-packed array provides flexibility in the application of low-frequency and small-dimension underwater acoustic sources.

自己整列微粒子の形状転写によるマイクロレンズアレイの製作とモールド変形を利用した非球面化の検討

Aspheric micro-lens arrays have been attracting great attention to improve light distribution control. This study proposes a simple and efficient method for fabricating close-packed aspheric micro-lens array. First, silica particles of ϕ10 μm were self-assembled over ϕ10 mm area using sedimentation method. Then the convex profile of the self-assembled particles was replicated to a spherical micro-lens array mold. The mold material was silicone elastomer or polydimethylsiloxane (PDMS). Then, the mold profile was replicated into ultraviolet (UV) curing resin. By applying uniaxial stretching to the mold during the secondary replication, aspheric micro-lens array was fabricated. Deformation of the PDMS mold under uniaxial stretching was analyzed by using finite element analysis (FEA) for rough estimation. Experimental results showed that intended lens profile was obtained though some defects were observed due to the nonuniformity of the particle diameters. Optical characteristic of elliptic micro-lens array was made clear.

Design, finite element analysis, fabrication and electroacoustic characterization of transducer arrays from piezoceramics with hollow cylindrical shell form

Electroacoustic transducers arrays operating in the 50–100 kHz frequency range are currently being investigated for underwater applications such as target detection transducers installed on underwater autonomous vehicles (UAV) and detection of underwater intruders to protect and secure economically and strategically critical coastal areas and facilities. However, the frequency range is such that it prevents the use of monolithic piezoceramics operating in the thickness mode due to the unacceptably high voltages that are required to drive them. Whereas the alternative such as Langevin-type transducer solutions have certain other assembly difficulties that arise due to the size limitations imposed on the transducer from the half-wavelength (λ/2) arrangement requirement of the units. In our study, an entirely new alternative was proposed to overcome these difficulties. A piezoceramic transducer constructed from a hollow cylindrical shell form poled in the radial direction was designed and developed to operate at the longitudinal length extension mode. Since the hollow cylindrical piezoceramics were designed and produced with one end closed, this closed end was used as a passive cap with the transducer operating in a piston mode. ATILA finite element analysis code was used to design, analyze and fine-tune the dimensional requirements of the transducer. The center frequency of the transducer was fixed to 70 kHz. Commercial lead zirconate titanate (PZT) composition with hard piezoelectric character (PZT-4) was used as the starting powder. The slip casting method was used to obtain the cylindrical shell form. Single element transducers, as well as a hexagonal close-packed array consisting of seven units and arranged with a distance of half-wavelength (λ/2) to obtain constructive interference at 70 kHz were constructed and tested for underwater electroacoustic performance.

Experimental and Theoretical Insight into the Facet-Dependent Mechanisms of NO Oxidation Catalyzed by Structurally Diverse Mn2O3 Nanocrystals

Crystalline structure of metal oxides is based on a close-packed array of oxygen anions with metal cations occupying interstitial sites, where the exposed facet determines the surface arrangement and coordination of oxygen and metal ions. Owing to the different physicochemical properties of various ions, the exposed crystal facets have a critical influence on properties of metal oxides, including catalytic behavior. Understanding the facet-dependent mechanisms of catalytic reactions is important for improving the performance of metal oxide catalysts; however, this understanding is currently lacking because research performed to date has been limited by the unilateral experimental or theoretical evidence. Herein, we aim to elucidate the effect of different exposed crystal facets in Mn2O3 by constructing rod- and particle-like Mn2O3 nanocrystals and investigating the effects on the catalytic performance of these structures for NO oxidation. Distinct catalytic behaviors of these different nanocrystals are investigated by a combination of systematic structural and property characterizations and density functional theory (DFT) calculations. Our results suggest that NO oxidation on the surface of rod-like Mn2O3 with exposed (220) and (400) facets follows the Langmuir–Hinshelwood mechanism, whereas the Mars–van-Krevelen mechanism is favored for Mn2O3 nanoparticles with exposed (222) facets. These different mechanisms lead to diverse catalytic performances of Mn2O3, especially the poisoning resistance. Specifically, rod-like Mn2O3 is shown to be deactivated by H2O because hydroxylated oxygen inhibits the adsorption of NO and adsorbed OH* hinders the chemisorption of O2 on the (220) and (400) facets, while H2O only slightly influences the activity of Mn2O3 nanoparticles with (222) facets. This work shows that regulating which crystal facets of Mn2O3 are exposed allows tuning the catalytic performance of this material and the reaction pathways for NO oxidation. Furthermore, this work provides clear insight that may increase the understanding of facet-dependent reaction mechanisms of other metal oxide catalysts and establishes valuable design principles for future studies to improve heterogeneous catalysts.

Optimization of microsphere optical lithography for nano-patterning

We present an original approach to realistic modeling of light focusing by microsphere systems to form the photonic jets for nano-patterning of the substrates with high refractive index. In simulations we analyze the photonic jets produced by a single sphere and close-packed array of microspheres on the photoresist layer and Si substrate. We show how the lithographic profiles can be controlled by varying the exposure dose and system geometry in wide ranges of photoresist layer thicknesses and microsphere sizes. The modeling covers the entire lithographic system and accounts for the interference of focused light transmitted through the microlenses and reflected from the Si substrate. We use our approach to optimize the size of the lithographic pattern and confirm the simulation results experimentally. The suggested set of methods is rather universal and may be applied to other microlens and resist materials to minimize lithography lateral resolution.

Studies on transmittance modulation and ions transfer kinetic based on capacitive-controlled 2D V2O5 inverse opal film for electrochromic energy storage application

Two-dimensional vanadium pentoxide inverse opal (2D V2O5 IO) architecture was fabricated by polystyrene (PS) sphere template assisted electrodeposition process. In comparison to the un-templated V2O5 film, the 2D V2O5 IO film exhibited a highly ordered hexagonal close-packed bowel-like array, as well as noticeable electrochromism, such as transmittance modulation up to 42.6% at 800 nm, high coloration efficiency (28.6 cm2 · C−1), fast ions transfer kinetic (t b = 7.2 s, t c = 2.5 s). These improvements of electrochromic performance were attributed to the ordered morphology with larger surface areas, which considerably shortened the ions diffusion paths and accelerated ions migration. An electrochromic energy storage device assembled from the 2D V2O5 IO film with simultaneous electrochromic and pseudocapacitive performance could not only show transmittance modulation accompanied by multicolor variations but also powered an LCD screen and an LED bulb, demonstrating a promising potential for practical applications.

A numerical study on the closed packed array of gold discs as an efficient dual mode plasmonic tweezers

In this report, we propose the closed pack array of gold discs on glass, as a dual mode plasmonic tweezers that benefits from two trapping modes. The first trapping mode is based on leaky surface plasmon mode (LSPM) on the gold discs with a longer penetration depth in the water and a longer spatial trapping range, so that target nanoparticles with a radius of 100 nm can be attracted toward the gold surface from a vertical distance of about 2 µm. This trapping mode can help to overcome the inherent short range trapping challenge in the plasmonic tweezers. The second trapping mode is based on the dimer surface plasmonic mode (DSPM) in the nano-slits between the neighboring gold discs, leading to isolated and strong trapping sites for nanoparticles smaller than 34 nm. The proposed plasmonic tweezers can be excited in both LSPM and DSPM modes by switching the incident wavelength, resulting in promising and complementary functionalities. In the proposed plasmonic tweezers, we can attract the target particles towards the gold surface by LSPM gradient force, and trap them within a wide half widthhalfmaximum (HWHM) that allows studying the interactions between the trapped particles, due to their spatial proximity. Then, by switching to the DSPM trapping mode, we can rearrange the particles in a periodic pattern of isolated and stiff traps. The proposed plasmonic structure and the presented study opens a new insight for realizing efficient, dual-mode tweezers with complementary characteristics, suitable for manipulation of nanoparticles. Our thermal simulations demonstrate that the thermal-induced forces does not interefe with the proposed plasmonic tweezing.

Lost horses on the frontier: K2BiCl5 and K3Bi2Br9

Two missing members, K3Bi2Cl9 and K3Bi2Br9, within the series of Bi-containing defect perovskite halides A3Bi2X9 were sought. K3Bi2Cl9 could not be obtained, but the previously identified but uncharacterized compound K2BiCl5 was prepared. K3Bi2Br9 was successfully prepared. K2BiCl5 and K3Bi2Br9 were synthesized by reactions of binary halides at 450–500 ​°C and their structures were determined by single-crystal X-ray diffraction methods. K2BiCl5 adopts the K2PrCl5-type structure in orthorhombic space group Pnma with Z ​= ​4 and cell parameters of a ​= ​12.5461(7) Å, b ​= ​8.7630(5) Å, and c ​= ​7.9865(5) Å. This structure features one-dimensional columns of edge-sharing BiCl7 capped octahedra. K3Bi2Br9 adopts the Tl3Bi2Br9-type structure in monoclinic space group P21/c with Z ​= ​4 and cell parameters of a ​= ​18.718(3) Å, b ​= ​8.1148(13) Å, c ​= ​13.154(2) Å, and β ​= ​91.329(2)°. In this defect perovskite variant, Bi atoms occupy two-thirds of the octahedral sites formed by close-packed arrays of the K and Br atoms, and the BiBr6 octahedra are connected by corner-sharing within slabs. Among defect perovskite halides A3Bi2X9 containing corner-sharing octahedra, K3Bi2Br9 exhibits the greatest degree of distortion from the ideal cubic perovskite structure observed so far. The band gaps, as measured from optical diffuse reflectance spectra, are 2.8 ​eV for K2BiCl5 and 2.2 ​eV for K3Bi2Br9. Electronic structure calculations indicate an indirect gap for K2BiCl5 and a direct gap with rather flat bands for K3Bi2Br9.

Molecularly imprinted colloidal array with multi-boronic acid sites for glycoprotein detection under neutral pH

Glycoproteins play vital roles in living organisms and often serve as biomarkers for some disease. However, due to the low content of glycoprotein in biological fluids, selective detection of glycoproteins is still a challenging issue that needs to be addressed. In this study, molecularly imprinted colloidal array with multi-boronic acid sites for glycoprotein detection under physiological pH was proposed. Monodispersed glycoprotein imprinted particles (SiO2@PEI/MIPs) was first prepared based on surface imprinting strategy using horseradish peroxidase (HRP) as template, and polyethyleneimine (PEI) was used to increase the number of boronic acid groups. The binding experiment indicated that the SiO2@PEI/MIPs hold satisfactory adsorption capacity (1.41 μmol/g), rapid adsorption rate (40 min) and preferable selectivity toward HRP. Then the SiO2@PEI/MIPs was assembled into close-packed colloidal array to construct a label free optical sensor (denoted as GICA). Benefiting from the high ordered photonic crystal structure, binding of HRP onto the GICA could be directly readout from the changes in structure color and diffracted wavelength. The structure color of the GICA changed from bright blue to yellow with the diffraction wavelength red shifted 59 nm when the HRP concentration increased from 2.5 to 15 μmol/L. Importantly, the GICA was capable of detecting HRP from human serum samples. All those results indicated the potential of the GICA for naked-eye detection of glycoprotein.

Self-assembly of C[formula omitted] layers at Tl/NiSi[formula omitted] atomic sandwich on Si(111)

Self-assembled growth of C60 monomolecular layers at the atomic sandwich consisting of Tl-covered single-layer NiSi2 on Si(111) has been studied as a function of the density of the Tl atomic layer. It has been found that C60 fullerenes form hexagonal close-packed arrays. Within a C60 layer, fullerenes can form together with Tl atoms three distinct configurations which are reflected by difference of the C60 brightness, labelled as dim, normal and bright, in the scanning tunneling microscopy images. It has been elucidated that the bright fullerenes reside atop a completed Tl monolayer, in the case of the normal fullerenes one Tl atom directly beneath the given fullerene is missing, and under the dim fullerenes no Tl atoms are left. Using Tl deposition, it is possible to change the relative fractions of the dim, normal and bright fullerenes, in particular to fabricate the homogeneous C60 layers consisting exclusively of the fullerenes of a single type, normal or bright, depending on the desire.

Pyroelectricity of Lead Sulfide (PbS) Quantum Dot Films Induced by Janus-Ligand Shells.

Asymmetry is an essential property to control. To do that in nanocrystalline systems we have developed methods to produce Janus-ligand shells on otherwise symmetric PbS quantum dots (QDs). Here, we demonstrate that control by constructing a system that exhibits pyroelectricity built from spherical PbS QDs. We observed a pyroelectric current in two different configurations. In one configuration, the QDs are self-assembled into close-packed arrays while in the second configuration, the QDs are dispersed into an electro-inactive polymer, polydimethylsiloxane. Both exhibit a pyroelectric response. In the first configuration we estimate a lower limit of the pyroelectric coefficient to be 1.97 × 10-7 C/m2·K, which is likely limited by the degree of QD alignment during film formation but is already on par with common pyroelectric systems. Compared with inorganic ceramic-like and polymeric pyroelectric materials, pyroelectric films self-assembled from polar QDs are easier to prepare, responsive to light with different energies based on QD exciton energy, and the polarization of each QD could be easily tuned by constructing different Janus-ligand shells.

Direct-write microsphere photolithography of hierarchical infrared metasurfaces.

A direct-write configuration of microsphere photolithography (MPL) is investigated for the patterning of IR metasurfaces at large scales. MPL uses a self-assembled hexagonal close-packed array of microspheres as an optical element to generate photonic nanojets within a photoresist layer. The photonic jets can be positioned within the microsphere-defined unit cells by controlling the illumination's angle of incidence (AOI). This allows the definition of complex antenna elements. A digital micromirror device is used to provide spatial modulation across the microsphere arrays and coordinated with a set of stages providing AOI control. This provides hierarchical patterning at the sub- and super-unit cell levels and is suitable for a range of metasurfaces. The constraints of this approach are analyzed and demonstrated with a polarization-dependent infrared perfect absorber/emitter, which agrees well with modeling.

Reliable SERS detection of pesticides with a large-scale self-assembled Au@4-MBA@Ag nanoparticle array

The fabrication of sensitive and reliable interfacial plasmonic platform for measuring chemical contaminants in various phases is an exciting topic in the food industry and for environment monitoring. In this study, a high-performance surface-enhanced Raman spectroscopy (SERS) analytic platform was developed through self-assembly of the gold@4-mercaptobenzoic acid@silver nanoparticles (Au@4-MBA@Ag NPs) at the cyclohexane/water interface. By addition of the inducer ethanol, the Au@4-MBA@Ag NPs in aqueous phase was effectively migrated to the biphasic interface, forming a large-scale close-packed nanoparticle array. The average gap between adjacent nanoparticles was smaller than 3 nm, where intensive SERS “hot spots” were created for high-sensitive detection. Furthermore, using the sandwiched 4-MBA molecule as the internal standard to correct the Raman signal fluctuations, the point-to-point and batch-to-batch reproducibility of Au@4-MBA@Ag array were improved with lower relative standard deviation (RSD) values of 8.84% and 14.97%, respectively, and pesticides (thiram and thiabendazole) analysis in both aqueous and organic phases were achieved with higher accuracy (R2 of 0.986 and 0.990) as compared with those without 4-MBA correction (R2 of 0.867 and 0.974). The high-throughput fabrication of the self-assembled nanoparticle array is a promising approach for development of a sensitive and reliable SERS platform for chemical contaminants monitoring in multiphase.