Trapping Efficiency Research Articles

Enhancing Energy Storage Capacity of 3D Carbon Electrodes Using Soft Landing of Molecular Redox Mediators.

The incorporation of redox-active species into the electric double layer is a powerful strategy for enhancing the energy density of supercapacitors. Polyoxometalates (POM) are a class of stable, redox-active species with multielectron activity, which is often used to tailor the properties of electrochemical interfaces. Traditional synthetic methods often result in interfaces containing a mixture of POM anions, unreactive counter ions, and neutral species. This leads to degradation in electrochemical performance due to aggregation and increased interfacial resistance. Another significant challenge is achieving the uniform and stable anchoring of POM anions on substrates to ensure the long-term stability of the electrochemical interface. These challenges are addressed by developing a mass spectrometry-based subambient deposition strategy for the selective deposition of POM anions onto engineered 3D porous carbon electrodes. Furthermore, positively charged functional groups are introducedon the electrode surface for efficient trapping of POM anions. This approach enables the deposition of purified POM anions uniformly through the pores of the 3D porous carbon electrode, resulting in unprecedented increase in the energy storage capacity of the electrodes. The study highlights the critical role of well-defined electrochemical interfaces in energy storage applications and offers a powerful method to achieve this through selective ion deposition.

Linking marsh sustainability to event-based sedimentary processes: Impulsive river floods initiated lateral erosion of deltaic marshes

Salt marshes providing valuable services in buffering flooding risks are regarded as cost-effective coastal defense solutions. Given that eroding marsh cliffs will threaten the sustainability of these protective functions, there is a need for mechanistic understanding of cliff formation. Based on short-term field measurements together with satellite-derived dataset and a morphodynamic model, we determined the response of marsh lateral dynamics to event-based sedimentary processes in the Yellow River Delta, China. It was found that the Eastern Marsh with a cliff of ∼1.2 m in height significantly differed from the gentle Western Marsh in accretion pattern and lateral dynamics. Attributed to an artificial flood lasting ∼20 days in 2022, the Eastern Marsh platform experienced average vertical accretion of 23.3 mm, ∼5 times higher than the Western Marsh barely impacted by fluvial sediment supply. Although the accretion pattern ensured the overall vertical adaptability, Eastern Marsh has translated from a phase of rapid expansion to lateral retreat of ∼60 m/yr since 2018, whereas Western Marsh was relatively stable in recent decade. With a validated delta-marsh model, we showed that the observed disparities were attributed to different marsh edge morphodynamic responses to river flood sediment supplies. When Spartina alterniflora initially colonized, the Eastern Marsh platform was lower and the trapping efficiency could rise by ∼3 times than the present. Integrating with ten-fold increases in sediment loads, it was estimated that the large artificial floods in 2018 could contribute to a vertical growth approximating 30 cm at Eastern Marsh. Such episodic but rapid marsh accretion played a crucial role in initiating the development of marsh cliff. Driven by positive feedbacks between platform elevations and cumulative wave thrust, a series of event-based marsh sedimentation will promote long-term marsh loss caused by lateral retreat at sediment-starved systems. This study provides insights in predicting marsh sustainability and long-term evolutions under episodic sedimentary events.

Trapping of microplastics and other anthropogenic particles in seagrass beds: Ubiquity across a vertical and horizontal sampling gradient

Seagrass beds can trap large amounts of marine debris leading to areas of accumulation, known as ‘sinks’, of anthropogenic particles. While the presence of vegetation can enhance accumulation, less is known about how the trapping effect changes from vegetated to less vegetated patches. To test this, vegetation and sediment were sampled along a vegetation percent cover gradient from the centre of seagrass beds to nearby less vegetated patches. To determine whether trapped particles can lead to increased accumulation in associated fauna, gastropods were also collected from the transects laid across this gradient. Extracted anthropogenic particles were counted and characterised. Particles were detected in all sample types and reached quantifiable limits in at least 50% of sediment and gastropod samples. There was no significant difference in the distribution of particles found in seagrass beds compared to less vegetated patches, suggesting other factors contribute to the trapping efficiency of biogenic habitats besides simply the presence or absence of vegetation.

Exploiting graded triangular gratings for optimal nano-focusing: A novel approach to enhance SERS efficiency

Plasmonic graded nano-gratings enable rainbow trapping of multiple resonant modes over a wide wavelength spectrum, useful for multi-channel Surface Enhanced Raman Spectroscopy (SERS) of molecular species. However, rectangular nano-gratings have limitations in achieving efficient rainbow trapping and localizing a wide spectrum of plasmonic modes due to their stepwise geometry, which induces high dissipation of surface plasmon polaritons into the substrate. An alternative platform of graded triangular nano-gratings enables increased localization and more efficient adiabatic transformation between neighboring grooves. Varying groove angles, depths, and periods in the tapered geometry allow for smooth adjustment of the surface plasmon polariton propagation constant, reducing losses and maximizing nano-focusing inside the groove tips. To overcome the limitation of low aspect ratio in wet-etching silicon, we employed a multi-step process of reactive ion etching of a SiO2 barrier layer to generate aperture width, followed by anisotropic wet-etching. The resulting graded triangular nano-gratings showed excellent SERS enhancement along three laser wavelength excitations. The enhancement factors of 638 and 785 nm wavelengths are 8.5 × 109 and 9 × 108, respectively, for the detection of 1 µM Rhodamine 6G. In addition, graded triangular nano-gratings show similar enhancement factors for other species, specifically the lipid DPEE-PEG, at the 532 nm laser excitation wavelength with an excellent SERS enhancement factor of 1.5 × 109. Owing to the ability of the graded triangular gratings to elicit pronounced SERS responses across three distinct laser excitations, they unequivocally qualify as “rainbow trapping” structures. Wider apertures, lower ohmic losses, and the ability to tune the groove angle beyond conventional etching methods bode well for graded triangular gratings as a superior platform for miniature sensors.

Developed Photocatalytic Cotton Fabric with Agricultural By-Products Tea Saponins for Accelerating Aqueous Chromium(VI) Reductive Removal

ABSTRACT In order to achieve the goal of preparing functional textiles using tea saponin, in this work, carboxymethylated tea saponin (CTS) was used to modify cotton fabrics by an industrial rolling and baking process, and then functional textiles could be obtained after coordination with Fe3+, which could remove Cr species from water by photocatalytic reduction and adsorption processes. High CTS concentrations and higher treatment temperatures led to an increase in the carboxyl group content (QCOOH) and Fe content (QFe) of the obtained Fe-CTS-Cotton. The increase in the QFe value of the functional textiles favored the photocatalytic reduction of Cr(VI). Fe-CTS-Cotton with high QCOOH values showed excellent adsorption performance for the generated Cr(III) ions during the adsorption process. Therefore, the high photocatalytic reduction efficiency and strong Cr(III) ion trapping ability were the reasons for the recycling of Fe-CTS-cotton as a hybrid photocatalyst for enhanced removal of Cr(VI).

Unveiling the Computational Insights into Na‐Decorated Hydrogen‐Substituted Graphdiyne for Efficient Tracing and Trapping of Nitrogen and its Oxides

Addressing air pollution is a critical concern, particularly in the context of tracing and trapping nitrogen and its oxides (N2, N2O, NO, NO2) emitted from fuel combustion. In this context, this study delves into the potential of recently discovered Hydrogen-substituted Graphdiyne (HsGDY) and to enhance its adsorption capabilities by incorporating sodium (Na) metal atom computationally. Herein, the strategic sites for Na atom decoration on HsGDY is identified and the most stable site R1 with Eads = −0.820 eV is chosen for subsequent NOx adsorption studies. Through DFT calculations, we assess the adsorptive capacity of NOx gases onto both HsGDY and Na-decorated HsGDY (NaHsGDY) slabs. In particular NO2 gas molecule with Eads = −2.537 eV emphasizes greater adsorption over NaHsGDY slab. Analysis of electronic properties reveals significant reduction in the energy gap (Eg) of the NaHsGDY, indicating heightened reactivity toward NOx gases thereby resulting in substantial increase in the slab’s conductivity. Additionally, charge density difference and Löwdin charge analyses provides consistent evidence supporting enhancement in charge transfer during NOx gases adsorption after Na decoration. The NaHsGDY slab demonstrates high selectivity, sensitivity, and superior performance than HsGDY slab, positioning it as a promising candidate for targeted NOx gas molecules detection.

Multi-hierarchical CuS/SnIn4S8 S-scheme heterojunction for superior photothermal-assisted photocatalytic hydrogen production

Various methods aimed at enhancing light trapping and charge separation efficiencies have emerged as a central research focus in the field of photocatalysis. This study marks the successful construction of CuS/SnIn4S8 composite photocatalysts for the first time. Firstly, the interesting multi-hierarchical architecture enables efficient light harvesting and abundant active sites. Secondly, the excellent photothermal effect of the composite makes its surface temperature reach up to 173 °C after 300 s exposure to simulated sunlight. Thirdly, the S-scheme heterojunction establishes a unique channel guaranteeing improved charge separation and transfer as well as boosted charge reactivity. Thanks to these synergistic effects, the developed CuS/SnIn4S8 heterostructure demonstrates superior solar-driven photocatalytic water splitting for hydrogen production, with an average hydrogen evolution rate of as high as 6235.72 μmol g−1 h−1, which is 20 times and 4 times higher than that of single-phase CuS and SnIn4S8, respectively. This work proposes a novel concept for the design of photothermal-assisted composite photocatalysts.

Constructing Sequential Type II Heterojunction CQDs/Bi2S3/TiNbO Photoanode with Superior Charge Transfer Capability Toward Stable Photoelectrochemical Water Splitting.

Efficient charge transfer and light-trapping units are pivotal prerequisites in the realm of Ti-based photoanode photoelectrochemical (PEC) water splitting. In this work, we successfully synthesized a ternary carbon quantum dots/Bi2S3 quantum dots/Nb-doped TiO2 nanotube arrays (CQDs/Bi2S3/TiNbO) composite photoanode for PEC water splitting. CQDs/Bi2S3/TiNbO composite photoanode exhibited a considerably elevated photocurrent density of 8.80 mA cm-2 at 1.23 V vs the reversible hydrogen electrode, which was 20.00 times better than that of TiO2 (0.44 mA cm-2). Furthermore, the CQDs/Bi2S3/TiNbO composite photoanode attested to exceptional stability, maintaining 92.54% of its initial current after 5 h of stability measurement. Nb-doping boosted the electrical conductivity, facilitating charge transfer at the solid-liquid interface. Moderate amounts of Bi2S3 quantum dots (QDs) and CQDs deposited on TiNbO provided abundant active sites for the electrolyte-photoanode interaction. Simultaneously, Bi2S3 QDs and CQDs synergistically functioned as light-trapping units to broaden the light absorption range from 396 to 530 nm, stimulating increased carrier generation within the composite photoanode. In comparison with pristine TiO, CQDs/Bi2S3/TiNbO photoanodes possessed a superior ability to promote interfacial reactions. This study may provide a strategy for developing high-performance Ti-based photoanodes with efficient charge transfer and light trapping units for highly driving solar-to-hydrogen conversion.

Efficient trapping of lithium-ions by branched amine for stable lithium metal anodes

Lithium metal batteries (LMBs) have attracted wide attention as high-energy–density energy storage devices, but their practical applications are hindered due to capacity degradation and safety concerns arising from the growth of lithium (Li) dendrites. The interaction between the electrode and Li, encompassing both Li-ions and Li metal, display significant potential for solving Li-dendrite issues in LMBs. Here, a novel strategy is reported to thin hybrid coating (∼1.3 μm) comprising highly polar poly(vinylidene fluoride) (PVDF) and branched poly(ethyleneimine) (PEI) onto Cu foil, employed as a current collector for the Li metal anode. The branched PEI contains amine group side chains that effectively capture Li ions, thereby facilitating rapid Li-ion transfer kinetics. Moreover, the inclusion of PEI enhances the surface energy of the polymer coating, leading to a reduction in the nucleation radius of Li and the promotion of uniform Li deposition. When coupled with a LiFePO4 (LFP) cathode, the Li-E40V@Cu||LFP full cell demonstrates an impressive initial capacity of 141.8 mA h g−1, which remains at 118.1 mA h g−1 after 518 cycles at 1C (1C = 170 mA h g−1). This investigation presents a novel approach to alleviate the formation of dendrites on Li metal anodes.

Li2ZnTi3O8 as the host-separator modifier with efficient polysulfides trapping and fast Li+ diffusion for lithium-sulfur batteries

Li2ZnTi3O8 as the host-separator modifier with efficient polysulfides trapping and fast Li+ diffusion for lithium-sulfur batteries

Lateral heterostructures of WS2 and MoS2 monolayers for photo-synaptic transistor

Von Neumann architecture-based computing, while widely successful in personal computers and embedded systems, faces inherent challenges including the von Neumann bottleneck, particularly amidst the ongoing surge of data-intensive tasks. Neuromorphic computing, designed to integrate arithmetic, logic, and memory operations, has emerged as a promising solution for improving energy efficiency and performance. This approach requires the construction of an artificial synaptic device that can simultaneously perform signal processing, learning, and memory operations. We present a photo-synaptic device with 32 analog multi-states by exploiting field-effect transistors based on the lateral heterostructures of two-dimensional (2D) WS2 and MoS2 monolayers, formed through a two-step metal–organic chemical vapor deposition process. These lateral heterostructures offer high photoresponsivity and enhanced efficiency of charge trapping at the interface between the heterostructures and SiO2 due to the presence of the WS2 monolayer with large trap densities. As a result, it enables the photo-synaptic transistor to implement synaptic behaviors of long-term plasticity and high recognition accuracy. To confirm the feasibility of the photo-synapse, we investigated its synaptic characteristics under optical and electrical stimuli, including the retention of excitatory post-synaptic currents, potentiation, habituation, nonlinearity factor, and paired-pulse facilitation. Our findings suggest the potential of versatile 2D material-synapse with a high density of device integration.

Simulation of CO2 dissolution reactions in saline aquifers using lattice Boltzmann method

CO2 dissolution reactions in saline aquifers during geologic carbon sequestration (GCS) involve multiple physicochemical processes and pose a challenge for both experimental and numerical techniques to capture reactive transport features and complex porous structures. Benefited from advanced models in the lattice Boltzmann (LB) community, namely, multiphase flow LB model and multicomponent transport LB model with chemical reactions, dynamics of CO2-water interfaces, concentration evolution of ions, and heterogeneous and homogeneous reactions could be readily captured by the proposed LB model to characterize CO2 dissolution reactions applicable to far-field applications. This LB model can not only emphasize CO2 dissolution processes at the scale of a few pores but also elaborate on the corresponding controlling mechanisms in porous media during GCS in saline aquifers. LB simulations herein indicate that both diffusion coefficient and reactive interfacial length may change the total concentration gradient at the CO2-water interface to further affect CO2 dissolution reactions. It is also confirmed that CO2 dissolution is a non-equilibrium process, which could not be neglected in reservoir-scale simulations. The effect of reactive interfacial length on CO2 dissolution is negligible due to a narrower range of contact angles in saline aquifers. Influenced by the structural complexity of porous media, the dissolution of CO2 clusters shows a strong heterogeneous characteristic evaluated by the pore size distribution. The evolution of pH in homogeneous reactions is estimated via mass action equations. Besides, the effects of partial pressure, formation temperature, and salinity, as three key factors in the practical application, are thoroughly probed. The high pressure is conducive for sequestration because of its greater sequestration efficiency, but the temperature has both positive and negative impacts on CO2 dissolution trapping and should be carefully evaluated in a certain saline aquifer before the operation. High ion strength would decrease the efficiency of dissolution trapping to some extent.

Comparative Efficacy of the Different Power Sources in Light Trap during Rabi Season

The present investigation entitled, “Comparative efficacy of different power sources in light trap against major phototactic insect pest of rabi season” was carried out at the BSP (Breeder Seed Production) Farm, Adhartal, JNKVV, Jabalpur (MP) during rabi (mid-November 2022 to mid-April 2023) season 2022-2023.Four light traps design were used in study via. T1 – Solar light trap (with 40 cm funnel diameter, T2 – Solar light trap (50 cm funnel diameter), T3 – Electrical light trap (with 40 cm funnel diameter), T4 – Electrical (with 50 cm funnel diameter). All four light traps were operated every evening and collection was collected every morning for the duration of the investigation for 12 species viz., Helicoverpa armigera, Agrotis ipsilon, Creatonotus gengis, Spodoptera litura, Gryllus bamaculatus, Gryllotalpa orientalis, Nezara viridula, Amata cyssea, Asota ficus Perina nuda, Thysanoplusia orichalcea and Theretra oldenlandiae analysis daily data were combined into weekly totals, this data was subjected to analysis in paired and two sample t-test. In conclusion, electrical light traps were superior in terms of trapping efficacy compared to solar light traps for most of the species collected. The advantage of electrical light traps is in their ability to provide continuous illumination while the power is on, which ensures a higher attraction and capture rate of insects. On the other hand, solar light traps have limitations in providing consistent and sustained light throughout the night, potentially leading to reduced trapping efficiency.

Estimating the useful life of the sempor reservoir using erosion modelling

Sedimentation determines how optimal a reservoir functions throughout its design life. The Sempor Reservoir in Central Java, Indonesia, will be 45 years old in 2023. At least 15 million m3 of particles have been sedimented in the reservoir for >30 years, reducing its function as an irrigation water source to only 60%. Therefore, assessing its performance in providing irrigation water and generating hydropower electricity is essential, given that its design life ends in 2028. This study was conducted to analyse the sedimentation and estimate the useful life of the Sempor Reservoir based on the erosion potential in its catchment area. The potential sedimentation rate was formulated from erosion potential assessed using the universal soil loss equation (USLE) model, sediment delivery ratio (SDR) and trap efficiency (TE). By contrast, the actual sedimentation rate was determined from changes in the dead storage capacity from 2013 to 2023. The interpolation performance evaluation of the bathymetric survey results was tested using the coefficient of determination (R2), Nash-Sutcliffe efficiency (NSE), and mean absolute percentage error (MAPE) which resulted in values of 0.917; 0.87; and 13.03%, respectively. The results show that the catchment area had an erosion potential of 3,405,353.86 t∙a−1, resulting in a potential sedimentation rate of 309,106.63 m3∙a−1. The calculated actual sedimentation rate was 33,903.28 m3∙a−1. Therefore, the useful life of the Sempor Reservoir was estimated to end in 0.5 years and 4.59 years based on the potential and actual sedimentation rates, respectively.

Au@ZnS core–shell nanoparticles decorated 3D hierarchical porous TiO2 photocatalysts for visible-light-driven CO2 reduction into CH4

Hereby, the core–shell structured Au@ZnS nanoparticles were precipitated on three-dimensionally ordered macro-mesoporous TiO2 (Au@ZnS/3DOMm-TiO2) by GBMR/P method. The slow photon effect of 3DOM structure leads to increase the light trapping and absorption efficiency. The hierarchical porous structure improves the specific surface area of the carrier, providing a larger internal void for desorption of reaction products and additional activation sites for the CO2 reduction. In the all-solid Z-scheme system, electrons are transferred along the direction from TiO2 to Au and finally to the surface of ZnS is realized to participate in the reaction of CO2 reduction. Under irradiation of visible light, ternary Au@ZnS/3DOMm-TiO2-2 catalyst exhibits the highest catalytic activity for CO2 photoreduction with H2O, i.e., the formation rate and selectivity of CH4 product is 33.2 µmol g-1h−1 and 91.5 %, respectively. The design of Z-scheme heterojunctions on 3D macro-mesoporous oxide surfaces are expected to expand new ideas for the preparation of efficient photocatalysts.

Smart 3D Ag-decorated TiO2 Nanostructure: An advanced synergistic SERS substrate for trace detection of analytes with diverse natures

Designing surface-enhanced Raman scattering (SERS) substrates that combine multiple advanced features in synergy is highly desirable for the SERS technique, however, it has been a long-standing challenge due to inherent trade-offs in feature selection. For instance, while nanoplasmonic surface functionalization bolsters attraction to target analytes, it simultaneously introduces barriers to direct contact. Similarly, the intrinsic hydrophilic or hydrophobic nature of substrates often limits their sensing effectiveness across a wide range of analyte types. Here, we demonstrate a smart 3D Ag-decorated TiO2 nanostructure, an advanced synergistic SERS substrate, created by controlling the formation of Ag nanoparticles on functionalized TiO2 nanomaterials, which integrates four unique features: uniform hotspot distribution, efficient analyte trapping, accessible plasmonic surfaces, and dual-phase detection. This design brings unachieved sensor efficiency across a diverse array of analytes with varying sizes and hydrophobicity. Moreover, our design exhibits a novel dual-phase detection capability within mixtures of hydrophilic and hydrophobic analytes. As a proof-of-concept, our results highlight the potential of designing SERS substrates with multiple advanced features that work synergistically, enabling trace detection of a broader range of analyte types in various environments. More broadly, we anticipate that this work paves the way for the development of other nanomaterials that are capable of attracting diverse molecules while retaining key features such as accessible plasmonic surfaces and wide-area ordered hotspot distribution. Such nanomaterials could be powerful for advanced applications in hotspot engineering, surface analysis, catalysis, and plasmon-mediated reactions.

Using modified trapping regimes to understand the behavioral and spatial ecology of Philornis downsi (Diptera: Muscidae).

The avian vampire fly Philornis downsi (Dodge & Aitken) (Diptera: Muscidae) is native to continental South America and the Caribbean, but invasive in the Galapagos Archipelago. The larvae of P. downsi feed on the blood and tissues of the nestlings of 75% of the small land bird species that are endemic or native to Galapagos, causing high in-nest mortality and severe population declines in some species. Efficient trapping techniques are vital to safeguarding these birds in the short term as well as for monitoring fly populations, but basic information about the ecology of the fly is still needed to help develop a species-appropriate trapping method. In this study, we used a novel trapping regime with a vertical distribution to make inferences about P. downsi's behavioral and spatial ecology and to optimize trap catch. Our results showed that male and female P. downsi were trapped in greater numbers below the canopy (3.1-7.5 m), lower down than other commonly caught insect species (5.1-11.5 m). Notably, the effect of trap height remained consistent across seasons and different weather conditions. These findings suggest that P. downsi tend to move at heights where their hosts nest (at or below the canopy) and do not spend time above the canopy. This also makes it unlikely that strategies such as hill-topping or aerial swarming are being used to locate mates. As such, trapping and control efforts should be focused below the canopy in forests with similar canopy heights to effectively capture P. downsi and reduce bycatch of other insects.

Room-temperature strong coupling in a single-photon emitter-metasurface system

Solid state single-photon sources with high brightness and long coherence time are promising qubit candidates for modern quantum technology. To prevent decoherence processes and preserve the integrity of the qubits, decoupling the emitters from their surrounding environment is essential. To this end, interfacing single photon emitters (SPEs) with high-finesse cavities is required, especially in the strong coupling regime, when the interaction between emitters can be mediated by cavity fields. However, achieving strong coupling at elevated temperatures is challenging due to competing incoherent processes. Here, we address this long-standing problem by using a quantum system, which comprises a class of SPEs in hexagonal boron nitride and a dielectric cavity based on bound states in the continuum (BIC). We experimentally demonstrate, at room temperature, strong coupling of the system with a large Rabi splitting of ~4 meV thanks to the combination of the narrow linewidth and large oscillator strength of the emitters and the efficient photon trapping of the BIC cavity. Our findings unveil opportunities to advance the fundamental understanding of quantum dynamical system in strong coupling regime and to realise scalable quantum devices capable of operating at room temperature.

Electrostatically directed assembly of macroporous skeleton structured copper selenide for elemental mercury sequestration from coal-fired flue gas

Decontamination of Hg0 from coal-fired flue gas remains an enormous challenge. It is an imperative pursuit to design adsorbents bearing an abundance of accessible chelating sites with a high affinity toward mercury, thus achieving both rapid uptake and high capacity for Hg0. Herein, an electrostatically directed assembly strategy was designed to construct Cu2Se decorated commercial polyurethane sponge (Cu2Se/PUS) as an efficient Hg0 trap. The surface coverage of Cu2Se on the Cu2Se/PUS can be rationally adjusted by turning the charge density of Cu2Se and PUS. The saturated Hg0 adsorption capacity of Cu2Se/PUS was achieved at 217.04 mg g−1 (normalized to the Cu2Se coating amount), which was much higher than that of powdery Cu2Se (43.66 mg g−1). Multiform selenium active sites (Se- and Se2-) and copper-terminated active centers of Cu2Se/PUS co-participated in Hg0 adsorption, instead of the individual role of Se- over powdery Cu2Se. The macroporous skeleton structure and the highly dispersed Cu2Se boosted the diffusion of mercury to the active sites for immobilization, thus accelerating the consumption of multiple active sites on the Cu2Se/PUS. This work not only provided an efficient Hg0 trap but also showed great inspiration for the potential of electrostatically directed assembly methods in constructing adsorbents for diverse environmental remediations.

Silica seed particles improve the efficiency and throughput of nanoparticle acoustic trapping

Silica has rarely been used as a seed particle material in acoustic trapping of nanoparticles. Here we use fluorescent nanoparticles, which are frequently used as a model system, to demonstrate that throughput and nanoparticle trapping efficiency can be improved by using silica seed particles as opposed to traditionally used polystyrene seed particles. The 10 times larger dipole scattering coefficient of silica seed particles compared with polystyrene seed particles in water leads to a higher retention force against fluid flow and thus enables higher throughput. Seed particles retained at an actuation voltage of approximately 10 V p.p. can withstand flow rates up to 2100 ± 200 µl/min for silica and 200 ± 50 µl/min for polystyrene. Furthermore, silica is found to be 40%–2000% more efficient (number of trapped nanoparticles as measured by fluorescent intensity) than polystyrene seed particles in trapping 270-nm polystyrene nanoparticles from suspensions of 1010–1011 particles/ml. Moreover, after enriching nanoparticles into a silica seed particle cluster, the washing flow rate can be increased from 30 µl/min to 200 µl/min (the flow rate at which polystyrene clusters are unstable), halving the total sample processing time without losing the silica seed particle cluster or compromising the nanoparticle trapping efficiency. Thus, material properties (particularly density) of the seed particles are critical to both nanoparticle trapping efficiency and throughput. Published by the American Physical Society 2024