Silica Layer Research Articles

Stepwise ordering under nano-scale confinement in thin silica films

The phase transition from an amorphous 2D structure to a crystalline 3D structure under confinement is a fascinating and challenging problem in materials science and condensed matter physics. This work reports the Field Emission Scanning Electron Microscopy (FESEM) and energy dispersive analysis of X-rays (EDAX), X-ray diffraction (XRD), X-ray reflectivity (XRR), Fourier Transform Infrared Spectroscopy (FTIR) studies on pristine silica thin films. Silica was deposited on pristine Al (001) substrate (Alfa-Aesar) from tetraethyl orthosilicate (TEOS) precursor and thin films were spin-coated at different spinning frequencies under ambient conditions. The samples are highly porous and in-plane porosity varies from 30% to 60% as analyzed from both the FESEM and XRR and with increasing spinning frequency pores become more ordered. XRR shows that the samples are composed of two layers, a thick layer of aluminum oxide (Al2O3) as buffer layer and a layer of SiO2 on the top of the film. XRR shows sharp ordering rather than any layering. The film thickness varies from 90[Formula: see text]Å to 200[Formula: see text]Å and it shows a linear decay in the thickness of silica layer. In between 1000 and 1500[Formula: see text]rpm, XRR shows a sharp drop in the thickness of silica layer where thickness of this layer falls below the unit-cell dimension indicating higher-ordered crystallization under strained condition. XRD shows that there are no crystalline peaks coming from silica at lower rpm except the peaks of Al coming from the substrate. At 1000, 1200 and 1500[Formula: see text]rpm there is peak corresponding to the quartz, highly crystalline phase of SiO2 and where the substrate is slightly modified Al2O3. Reflection from (101) plane is prominent in all the films and it gives indication of formation 3D crystalline phase. Whereas FTIR shows that the Si–O stretching modes exhibit sharper and more defined reflectance peak compared to the broad bands observed in the samples in lower rpm. Observations suggest a clear indication of progressive ordering under confinement. To one extent, the results of XRR and FESEM will suggest the mechanism of transition from 2D amorphous to 3D crystalline phase under geometrical confinement effect and total confinement effect arising from thinning of the films with the increasing rpm, interfacial effect and on the other hand XRD and FTIR results will explain high ordering under confinement without any layering.

Impact of substrate thickness and surface roughness on Al/Ni multilayer reaction kinetics

Reactive multilayers comprising alternating nanoscale layers of Al and Ni, exhibit potential across various applications, including localized heating for welding and joining. Control over reaction properties is pivotal for emerging applications, such as chemical time delays or neutralization of biological or chemical weapons. This research offers insights into the intricate interplay between substrate thickness, surface roughness, and the behavior of Al/Ni reactive multilayers, opening avenues for tailored applications in various domains. To observe this interplay, silica with various thicknesses from 0.4 µm to 1.6 µm was deposited on polished single crystalline Si and rough poly‐Si base substrates. Additionally, to analyze the impact of varying silica thickness along the sample length on reaction behavior, silica in step‐like shape was fabricated. Subsequently, Al/Ni multilayers with 5 µm total thickness and 20 or 50 nm bilayer periodicities were deposited. Reaction velocity and temperature were monitored with a high‐speed camera and pyrometer. Results indicate that silica thickness significantly affects self‐propagation in multilayers. The reaction is not self‐sustained for silica layers ≤ 0.4 µm, depending on bilayer periodicity and substrate roughness. The velocity increases or decreases based on the direction of reaction propagation, whether it moves upwards or downwards, in relation to the thickness of silica.This article is protected by copyright. All rights reserved.

Micelles Cascade Assembly to Tandem Porous Catalyst for Waste Plastics Upcycling

AbstractCatalytic upcycling of polyolefins into high‐value chemicals represents the direction in end‐of‐life plastics valorization, but poses great challenges. Here, we report the synthesis of a tandem porous catalyst via a micelle cascade assembly strategy for selectively catalytic cracking of polyethylene into olefins at a low temperature. A hierarchically porous silica layer from mesopore to macropore is constructed on the surface of microporous ZSM‐5 nanosheets through cascade assembly of dynamic micelles. The outer macropore arrays can adsorb bulky polyolefins quickly by the capillary and hydrophobic effects, enhancing the diffusion and access to active sites. The middle mesopores present a nanoconfinement space, pre‐cracking polyolefins into intermediates by weak acid sites, which then transport into zeolites micropores for further cracking by strong Brønsted acid sites. The hierarchically porous and acidic structures, mimicking biomimetic protease catalytic clefts, ideally match the tandem cracking steps of polyolefins, thus suppressing coke formation and facilitating product escape. As a result, light hydrocarbons (C1‐C7) are produced with a yield of 443 mmol gZSM‐5−1, where 74.3 % of them are C3‐C6 olefins, much superior to ZSM‐5 and porous silica catalysts. This tandem porous catalyst exemplifies a superstructure design of catalytic cracking catalysts for industrial and economical upcycling of plastic wastes.

Micelles Cascade Assembly to Tandem Porous Catalyst for Waste Plastics Upcycling.

Catalytic upcycling of polyolefins into high-value chemicals represents the direction in end-of-life plastics valorization, but poses great challenges. Here, we report the synthesis of a tandem porous catalyst via a micelle cascade assembly strategy for selectively catalytic cracking of polyethylene into olefins at a low temperature. A hierarchically porous silica layer from mesopore to macropore is constructed on the surface of microporous ZSM-5 nanosheets through cascade assembly of dynamic micelles. The outer macropore arrays can adsorb bulky polyolefins quickly by the capillary and hydrophobic effects, enhancing the diffusion and access to active sites. The middle mesopores present a nanoconfinement space, pre-cracking polyolefins into intermediates by weak acid sites, which then transport into zeolites micropores for further cracking by strong Brønsted acid sites. The hierarchically porous and acidic structures, mimicking biomimetic protease catalytic clefts, ideally match the tandem cracking steps of polyolefins, thus suppressing coke formation and facilitating product escape. As a result, light hydrocarbons (C1-C7) are produced with a yield of 443 mmol gZSM-5 -1, where 74.3 % of them are C3-C6 olefins, much superior to ZSM-5 and porous silica catalysts. This tandem porous catalyst exemplifies a superstructure design of catalytic cracking catalysts for industrial and economical upcycling of plastic wastes.

Demonstration of 4H-silicon carbide on an aluminum nitride integrated photonic platform.

The existing silicon-carbide-on-insulator photonic platform utilizes a thin layer of silicon dioxide under silicon carbide (SiC) to provide optical confinement and mode isolation. Here, we replace the underneath silicon dioxide layer with 1-µm-thick aluminum nitride and demonstrate a 4H-silicon-carbide-on-aluminum-nitride integrated photonic platform for the first time to our knowledge. Efficient grating couplers, low-loss waveguides, and compact microring resonators with intrinsic quality factors up to 210,000 are fabricated. In addition, by undercutting the aluminum nitride layer, the intrinsic quality factor of the silicon carbide microring is improved by nearly one order of magnitude (1.8 million). Finally, an optical pump-probe method is developed to measure the thermal conductivity of the aluminum nitride layer, which is estimated to be over 30 times of that of silicon dioxide.

Enhanced spontaneous radiation of quantum dots based on modulated anapole states in dielectric metamaterial

Dielectric nanostructures exhibit low-loss electrical and magnetic resonance, making them ideal for quantum information processing. In this study, the periodic double-groove silicon nanodisk (DGSND) is used to support the anapole state. Based on the distribution properties of the electromagnetic field in anapole states, the anapoles are manipulated by cutting the dielectric metamaterial. Quantum dots (QDs) are used to stimulate the anapole and control the amplification of the photoluminescence signal within the QDs. By opening symmetrical holes in the long axis of the nanodisk in the dielectric metamaterial, the current distribution of Mie resonance can be adjusted. As a result, the toroidal dipole moment is altered, leading to an enhanced electric field (E-field) and Purcell factor. When the dielectric metamaterial is deposited on the Ag substrate separated by the silicon dioxide (SiO2) layer, the structure exhibits ultra-narrow perfect absorption with even higher E-field and Purcell factor enhancement compared to silicon (Si) nanodisks.

Surface-enhanced Raman scattering-fluorescence dual-mode probes for target imaging of tumors, organoids and cancerous cells

A dual-mode nanoprobe (DMNP) overcomes the limitations of single probes and offers superior performance by combining their advantages. Herein, we report a DMNP design that features a gold nanosphere core and two layers of silica wrapping. The gold core surface is coated with 4-mercaptobenzoic acid(4-MBA), which serves as a Raman reporter. After the initial silica encapsulation, fluorophores in the form of conjugated polymer nanoparticles (CPNs) are applied to the surface. Finally, the encapsulation process is completed by adding the second layer of silica. The probe has dual-mode capabilities, including surface-enhanced Raman scattering (SERS) with a Raman enhancement factor of 134.1, and metal-enhanced fluorescence (MEF) with a fluorescence enhancement factor of 1.42. When modified with glycoprotein-3 (GPC3) antibody, the DMNPs probe shows excellent performance in fluorescence and SERS imaging for HepG2 liver cancer cells. When DMNP is conjugated with the breast tumor-specific antibody CA153, the DMNPs-AbCA153 probe enables imaging and induces apoptosis of breast cancer cells. These probes can serve as a platform for visualizing the distribution of cancer cell surface markers by modifying antibodies to recognize the cell surface. They have also shown significant potential as probes for oncology diagnosis and treatment monitoring.

Propolis polyphenol nanosheet for synergistic cancer chemo-photothermal therapy

Two-dimensional (2D) carbon-based nanostructures hold great promise as near-infrared (NIR) photothermal materials, yet their widespread use has been hindered by labor-intensive and costly fabrication processes. Here, a novel, cost-effective approach is presented to produce photothermal materials derived from the polyphenolic fraction of propolis (PFP) for the first time. The method involves the pyrolysis of PFP under a neutral atmosphere, resulting in the formation of 2D PFP-based nanosheets (PFPNS) measuring 50–100 nm in size with efficient photothermal properties. Then, a layer-by-layer nanohybrid structure comprising PFPNS, polydopamine (PDA), mesoporous silica (MS), and polyethyleneimine (PEI) layers (PFPNS@PDA@MS-PEI) was designed as a versatile platform for drug delivery. Specifically, the anticancer drug doxorubicin (DOX) was loaded onto the nanohybrid (PFPNS@PDA@MS(DOX)-PEI) for targeted delivery to cancerous cells. Each layer of the nanohybrid serves a distinct purpose, enhancing functionality and efficacy. The NIR-responsive PFPNS@PDA component facilitates accelerated drug release and induces hyperthermic effects on cancer cells upon NIR irradiation. The MS structure enables high drug loading capacity (approximately 83.3%), while the pH-responsive PEI layer promotes cellular uptake and facilitates drug release within the acidic microenvironment of cancer cells. Combining NIR irradiation with chemotherapy results in a synergistic effect, leading to the eradication of 67% of MCF-7 breast cancer cells. The demonstrated efficacy, coupled with the non-toxic nature of the nanohybrid, positions it as a promising candidate for synergistic chemo-photothermal therapy of tumor tissues.

Low temperature PECVD processes for the fabrication of integrated symmetrical resonant UV210 organic/semiconductor structures

The resonant structures used as sensors for investigating specific dark and opaque substances may pose difficulties due to their potential aggressiveness towards photonic chips and the risk of destruction upon contact. To avoid it, this study presents a detailed description of a novel symmetrical waveguide structure with UV210 enclosed between Si/SiO2 bi-layers implemented for integrated photonics. The fabrication process is thoroughly explained, accompanied by various analyses conducted for characterizations purposes. The structure is composed of an organic UV210 material developed using deep UV lithography at 248 nm and fabricated onto an oxidized silicon layer, resulting in a Si/SiO2 bi-layer configuration. This process enables the fabrication of µm-scale access waveguides and racetrack Micro-Resonators (MRs) with a 400-nanometers gap. Several multilayer families have been produced using various low-temperature PECVD processes to obtain symmetrical Si/SiO2/UV210/Si/SiO2 structures and then properly characterized using non-destructive analyses and imaging techniques. The advantage of structural symmetry is primarily related to the electromagnetism and guidance equations, which eliminate the requirement for a cut-off thickness (or frequency), enabling significant miniaturization. Additionally, the upper cladding composed of a Si/SiO2 bi-layer offers protection against potentially aggressive substances directly in contact with the organic waveguide core and MRs. Different bi-layer upper cladding families, produced under various PECVD conditions, were characterized using XPS to understand the bonding mechanism between the silicon and UV210 organic. In addition, ellipsometric analyses were conducted to determine the real and imaginary components of the refractive index of the global structure and the upper cladding bi-layer. Structure imaging were obtained by Raman analyses and optical statistical measurements were conducted on four different types of heterostructures, with silica temperatures ranging from 120°C to 150°C during the second PECVD process. The resonance analysis, performed through Free Spectral Range (FSR) measurements, allowed us to draw conclusions regarding the stability and reproducibility of the fabrication process, as well as the impact of PECVD processes conditions on the optical measurements. Such optoelectronic resonant elements and hybrid heterostructures enable the investigation of aggressive substances in direct contact.

DNA Origami‐Directed Self‐Assembly of Gold Nanospheres for Plasmonic Metasurfaces

AbstractPlasmonic nanostructures are frequently utilized to create metasurfaces with a large variety of optical effects. Control over shape and positioning of the nanostructures is key to the function of such plasmonic metasurfaces. Next to lithographic means, directed self‐assembly is a viable route to create plasmonic structures on surfaces with the necessary precision. Here, a combined approach of DNA origami self‐assembly and electron beam lithography is presented for determinate positioning of gold nanospheres on a SiO2 surface. First, DNA origami structures bind to the electron beam‐patterned substrate and subsequently, gold nanoparticles attach to a defined binding site on the DNA origami structure via DNA hybridization. A sol‐gel reaction is then used to grow a silica layer around the DNA, thereby increasing the stability of the self‐assembled metasurface. A mean yield of 74% of single gold nanospheres is achieved located at the determinate positions with a spatial position accuracy of 9 nm. Gold nanosphere dimers and trimers are achieved with a rate of 65% and 60%, respectively. The applicability of this structuring method is demonstrated by the fabrication of metasurfaces whose optical response can be tuned by the polarization of the incoming and the scattered light.

Ar transport and blister growth kinetics in titania-doped germania-based optical coatings

Blistering is a phenomenon sometimes observed in sputtered-deposited thin films but seldom investigated in detail. Here, we consider the case of titania-doped germania (TGO)/silica multilayers deposited by ion beam sputtering. TGO is a candidate as high refractive index material in the Bragg mirrors for the next iteration of gravitational waves detectors. It needs to be annealed at 600 ∘C for 100 h in order to reach the desired relaxation state. However under some growth conditions, in 52-layer TGO/silica stacks, blistering occurs upon annealing at a temperature near 500 ∘C, which corresponds to the temperature where Ar desorbs from TGO. In order to better understand the blistering phenomenon, we measure the Ar transport in single layers of TGO and silica. In the case of < 1 µm-thick TGO layers, the Ar desorption is mainly limited by detrapping. The transport model also correctly predicts the evolution of the total amount of Ar in a 8.5 µm stack of TGO and silica layers annealed at 450 ∘C, but in that case, the process is mainly limited by diffusion. Since Ar diffusion is an order of magnitude slower in TGO compared to silica, we observe a correspondingly strong accumulation of Ar in TGO. The Ar transport model is used to explain some regimes of the blisters growth, and we find indications that Ar accumulation is a driver for their growth in general, but the blisters nucleation remains a complex phenomenon influenced by several other factors including stress, substrate roughness, and impurities.

Numerical demonstration of an efficient up-conversion enhancement strategy by plasmon excitations in a gap-mode nanocavity

Lanthanide-doped up-conversion nanoparticles (UCNPs) can be widely used as near-infrared absorbing photoactive materials in bioimaging and photovoltaic devices. However, the low absorption cross section and low luminescence quantum rate of UCNPs significantly limit its use. Therefore, a hexagonal gold pillar nano-array structure consisting of UCNPs, gold pillar arrays, gold film and silica layer is proposed. By optimizing the structural parameters, the surface plasmon resonance wavelengths are simultaneously matched with the 808 nm excitation wavelength and 450 nm emission wavelength of the UCNPs. The gap-mode nanocavity confines the incident excitation radiation to nanophotonic hotspots with greatly high field strengths, thus theoretically proposed an efficient strategy to enhance the up-conversion luminescence. The plasmonic structure investigated in this study combines the advantages of ease of processing, high absorption, low loss and good controllability of its localized surface plasmon resonance. It provides a new solution for up-conversion enhancement design of gap-mode nanocavities.

Photonic Bandgap Properties of One-Dimensional Bilayer Periodic Structure Composed of Silicon Dioxide and Gallium Phosphide Material Layers

Photonic Bandgap Properties of One-Dimensional Bilayer Periodic Structure Composed of Silicon Dioxide and Gallium Phosphide Material Layers

Super-Nernstian pH detection using out-of-equilibrium body potential in silicon on insulator ISFET sensors: Proof-of-concept and optimization paths

In this work, we demonstrate pH sensing using the out-of-equilibrium body potential (VB) monitored in silicon-on-insulator (SOI) double-gate “ISFET-like” devices with deposited metal contacts. Similar to the behavior of a dual-gate ISFET, in this study, the conductive channel induced by the back-gate voltage at the silicon/buried oxide (Si/BOX) interface is modulated by the charges to-be-sensed that are intentionally placed on the top silicon oxide layer SiO2 covering the Si film. The detection of the surface charge modulation was evidenced by monitoring in real-time the out-of-equilibrium body potential, while the classic shift in the drain current served as control experiment and for benchmarking. These first experiments demonstrate the successful implementation of this new pH detection paradigm, with super-Nernstian sensitivity. To provide optimization options for the body-potential sensing, TCAD simulations of the pH sensors were performed in a 2D structure and illustrated the possibility to further enhance the device sensitivity with an optimized architecture. Moreover, the pH-induced shift occurs at very high applied gate biases for the drain current, contrary to the body potential, which implies a sensor with lower power consumption when VB is used as reading method. Thus, body potential monitoring provides a promising reading method to reach the required low-power consumption regime of the tomorrow’s sensing devices.

Comparison of p-n and p-i-n vertical diodes based on p-PMItz/n-Si, p-PMItz/n-4HSiC and p-PMItz/i-SiO2/n-Si heterojunctions

In this paper, we present a comprehensive comparison study between p-n and p-i-n vertical diodes employing diverse heterojunction configurations under dark conditions. The diodes are fabricated utilizing p-PMItz as the organic semiconductor layer interfacing with different inorganic substrates, including n-Si (n-type silicon), n-4HSiC (n-type 4H silicon carbide), and incorporating an intrinsic SiO2 (silicon dioxide) layer in the p-PMItz/i-SiO2/n++-Si configuration. The current–voltage and dielectric characteristics are analyzed to discern the performance discrepancies among these diode configurations. The influence of heterojunction interfaces and band alignments on device behavior is investigated, shedding light on the charge transport mechanisms within these structures. Our findings reveal distinct trends in device characteristics for p-n and p-i-n diodes, highlighting the significance of heterojunction design in optimizing device performance. This comparative analysis offers valuable insights for the development of efficient organic–inorganic hybrid diodes tailored for various optoelectronic applications.

Properties of silicon dioxide coatings obtained by nano physical vapor deposition (PVD) method on the titanium 13‐niobium 13‐zirconium alloy

AbstractSurface modification techniques play an important role in adjusting the physicochemical properties of titanium and its alloys. To reduce the penetration of alloying element ions into the body, various types of oxide coatings are used to protect it from the corrosive environment. Another important issue related to the surface layer requirement is ensuring an appropriate set of mechanical properties. Accordingly, in this study, the mechanical and electrochemical properties of the silicon dioxide layers formed by the deposition of nano physical vapor deposition on the surface of titanium and titanium 13‐niobium 13‐zirconium alloy samples were investigated. To evaluate the mechanical properties of the layers produced by this method, hardness tests were carried out, as well as tests on the adhesion of these layers to the metal substrate. On the other hand, electrochemical properties were studied using potentiodynamic measurements to assess the resistance to pitting corrosion, followed by impedance measurements to interpret the processes and phenomena occurring at the silicon dioxide layer/electrolyte interface. The data obtained showed different mechanical and electrochemical properties of the silicon dioxide layers generated with varying process parameters.

Silica-coated liquid metal nanoparticles with different stiffness for cellular uptake-enhanced tumor photothermal therapy

Cells can sense the mechanical stimulation of nanoparticles (NPs) and then regulate the cellular uptake process. The enhanced endocytosis efficiency can improve the concentration of NPs in tumor cells significantly, which is the key prerequisite for achieving efficient biological performance. However, the preparation methods of NPs with flexible and tunable stiffness are relatively limited, and the impact of stiffness property on their interaction with tumor cells remains unclear. In this study, soft liquid metal (LM) core was coated with hard silica layer, the obtained core-shell NPs with a wide range of Young's modulus (130.5 ± 25.6 MPa - 1729.2 ± 146.7 MPa) were prepared by adjusting the amount of silica. It was found that the NPs with higher stiffness exhibited superior cellular uptake efficiency and lysosomal escape ability compared to the NPs with lower stiffness. The silica layer not only affected the stiffness, but also improved the photothermal stability of the LM NPs. Both in vitro and in vivo results demonstrated that the NPs with higher stiffness displayed significantly enhanced tumor hyperthermia capability. This work may provide a paradigm for the preparation of NPs with varying stiffness and offer insights into the role of the mechanical property of NPs in their delivery.

Nd3+-sensitized multilayered rare-earth nanocrystals with enhanced NIR-IIb luminescence for high resolution optical imaging

Luminescence imaging in the second near-infrared (NIR-II) window, particularly within the NIR-IIb (1500–1700 nm) sub-window, has been utilized for both fundamental research and clinical applications due to its exceptional spatiotemporal resolution. Nevertheless, efficient contrast agents designed for NIR-IIb imaging are still scarce. Herein, a multilayered rare-earth nanocrystal (NaYF4:Yb,Er,Ce@NaYF4:Yb,Nd@NaYF4) with strong NIR-IIb luminescence was designed and synthesized. The doping of Ce3+ ions in the core effectively suppresses the upconversion and boosts the downconversion luminescence by populating the Er 4I13/2 level. Additionally, by separating the sensitizer (Nd3+) and the activator (Er3+) in different layers, we are able to maximize the light absorption around 800 nm and reduce the cross relaxations between rare-earth elements, which leads to a strong downconversion emission around 1530 nm under 808 nm excitation. After passivation with NaYF4 shell and phase transfer with highly PEGylated mesoporous silica layer, the nanocomposites with excellent colloidal stability and bright NIR-IIb emission were obtained. With long blood circulation time in vivo, the fabricated nanocomposites enable high resolution and contrast luminescence imaging of the blood vessels and tumors in living mice. Moreover, the rare-earth nanocrystals with superior optical properties also hold great promise for various applications in optical sensing and biomedical imaging.

Highly efficient anti-reflection coating on transparent material surface by a deposition-oxidation two-step process using very high-frequency plasma under atmospheric pressure

Using atmospheric-pressure (AP) helium (He)-based plasma excited by a 150 MHz very high-frequency (VHF) power, the formation of low-refractive-index silicon oxide (SiOx) layers for single-layer quarter-wave anti-reflection (AR) coatings of transparent substrate materials is studied. To effectively lower the refractive index of SiOx layers, a deposition-oxidation two-step process is adopted. Specifically, carbon and hydrogen-containing silicon oxide (SiOCH) films are coated in hexamethyldisiloxane and hydrogen-fed plasma on the substrates with fine polystyrene spheres arranged, and subsequently oxidized in oxygen-fed plasma. During the post-oxidation process, the SiOCH film is transformed into silica (SiO2)-like one and the polystyrene spheres underlying the film is simultaneously oxidized to be removed. As a result, a SiO2-like film with a very low refractive index of 1.23 and with excellent adhesion to the substrate is obtained. It is also demonstrated that the low-refractive-index coating functions well as a quarter-wave AR coating of a glass substrate.

Efficient Generation of Plasma‐Activated Aerosols with High Concentrations of Reactive Species via Silicon Dioxide Coated Surface Acoustic Wave Devices

AbstractAn effective method to deliver plasma‐activated water onto contaminated surfaces is with a surface acoustic wave (SAW) nebulizer that can efficiently produce plasma‐activated aerosols. While higher reactive species concentrations in the plasma‐activated aerosols promote more efficient bacterial inactivation and hence reduce the amount of aerosols needed to completely eradicate the bacteria colonies, higher concentrations of reactive species themselves are found to lead to lower nebulization rates due to the increased electrical conductivity of the solution. To circumvent this problem, it is shown that coating the SAW substrate with a thin insulating layer of silicon dioxide (SiO2) can significantly mitigate the nebulization rate reduction. Specifically, when the electrical conductivity increases from 0.25 to 4.0 mS cm−1, the 62% drop in the nebulization rate is observed with the uncoated SAW devices is substantially reduced to 19% simply with the SiO2 coating. This can be attributed to the synergistic effects of increased wettability and the suppression of the electrical body force acting on the liquid film. The concomitant increase in the bacterial colony reduction from 17% to 76% demonstrates this solution to be a facile yet effective way of enhancing the efficiency for spray‐based bacterial inactivation on contaminated surfaces.