Mist Deposition Research Articles

Thin Film Deposition and Optical Properties of Cs-Cu-I System Via Mist Deposition with Various Precursor Compositions

Thin Film Deposition and Optical Properties of Cs-Cu-I System Via Mist Deposition with Various Precursor Compositions

Ultrahigh Transparent Safety Film for Spectrally Selective Photo/Electrothermal Conversion via Surface-Enhanced Plasma Resonance Dynamics.

Traditional deicing methods are increasingly insufficient for modern technologies like 5G infrastructure, photovoltaic systems, nearspace aerocraft, and terrestrial observatories. To address the challenge of combining anti-icing efficiency with operational performance, an innovative, spectrally selective, photo/electrothermic, ice-phobic film was prepared through a cost-effective mist deposition method. By manipulating the diameter ratio and density of nanowires, the local density of free electrons within this film is controlled to precisely dictate the position and intensity of surface plasmon resonance to achieve spectrally selective photo/electrothermal conversion. Additionally, the synthesized hydrophobic N-Boroxine-PDMS/SiO2 layer improves thermal stability and accelerates the deicing process. It achieves rapid deicing within 86 s under photothermal conditions and 65 s with Joule heating while maintaining high optical transmittance. The film improves the operational efficiency and thermal safety of equipment while preserving aesthetics and stability, thereby underscoring its broad suitability for advanced outdoor installations in cold environments.

The deposition and the optical characteristics of Cu-based metal halide Cs3Cu2I5 thin film via mist deposition

Cu-based metal halides, such as Cs3Cu2I5, are promising materials for LEDs, photodetectors, and scintillators because of their excellent optical properties, nontoxicity, and high air stability. In this study, we demonstrated the deposition of high-coverage Cs3Cu2I5 thin films using solution-based mist deposition. By adjusting the substrate temperature appropriately, continuous Cs3Cu2I5 thin films were formed. The Cs3Cu2I5 thin films exhibited blue emission under ultraviolet irradiation, with a large Stokes shift of 1.40 eV. Furthermore, they exhibited a high photoluminescence quantum yield of over 80%.

Computational Fluid Dynamics Process for Front Windshield Mist Deposition and Its Subsequent Demisting

<div>A vehicle’s heating, ventilation, and air-conditioning system plays a dual role in passenger thermal comfort and safety. The functional aspects of safety include the front windshield demist and deicing feature of the system. The thin-film mist is a result of condensation of water vapor on the inner side of the windshield, which occurs at low ambient temperatures or high humidity. This mist deposition depends on the air saturation pressure at the front windshield. Indian regulation AIS-084 defines the experimental setup for testing, which encompasses both the mist deposition and its subsequent demist process. This regulation mandates testing, which occurs at a later stage of product development. This performance validation can be performed using a three-dimensional computational fluid dynamics approach.</div> <div>Current work summarizes the simulation process for both the mist deposition and the subsequent demisting phenomenon. The complexity of the flow physics is captured via the transient multiphase fluid flow phenomenon subjected to buoyancy effects. This phenomenon is simulated using the Eulerian wall film approach. The wall film deposition of the mist is modeled via species transport. Further, the near-wall thermal effects of surface conduction and heat transfer are simulated by modeling shell conduction layers. Vapor diffusion and relative humidity inside the cabin are modeled using a user-defined function. The process correlation is achieved for two categories of vehicles to establish the process efficacy and robustness. Moving ahead, a design of experiments (DOE) is planned to mitigate the need to simulate mist deposition. The DOE is planning to incorporate deviations in both the input airflow conditions and the imposed ambient conditions. The results from DOE point toward factors that might cause deviations in simulation results with respect to the test. Importantly, the study concludes that the uniform initial thickness assumption of the mist layer can be used for subsequent demist analysis.</div>

Modeling and Simulation of Coalescence in the Context of Oil Mist Filtration

Today, aerosols are generated in many industrial processes like machining or in pneumatic compressors. The harmfulness of these droplets often lies in the liquid itself, as it can be toxic or cancerous while exhaled natural aerosols can carry pathogens. For health protection, the filtration of these aerosols is an important task. The wetting properties of the fibers have a large influence on the filtration efficiency and coalescence of droplets on the fibers. Oleophilic fibers are better in capturing the oil particles, while drainage increases using oleophobic fibers. For improved efficiency and drainage properties, a mixed-wet fiber system could therefore be advantageous. Describing droplet capture and coalescence in filter-scale simulations is computationally extremely demanding. We present a new approach for simulating oil mist deposition and droplet coalescence, specifically accounting for the wettability of the fibers, especially for mixed-wet filter media. The aim is to gain a more realistic pressure loss of a fibrous filter structure which takes the presence of the filtered phase into account as well as the coalescence of the liquid phase on the fibers depending on the wettability and the fluid parameters. Our approach is to model the shape of deposited droplets via weighted distance maps, according to the contact angles. Starting from a sphere, the shape is fitted on the solid surface such that the contact angle is met. For validation purposes, volume-of-fluid-based simulations were set up using the same droplet-fiber system as a reference to compare the droplet shape and pressure loss in the presence of oil droplets on the fiber surface.

Evaluation of Soft Mist Inhaler Aerosol Velocity, Size, and Deposition Inside the Mouth-A Computational Fluid Dynamics Study.

Respiratory diseases debilitate more than 250 million people around the world. Among available inhalation devices, the soft mist inhaler (SMI) is the most efficient at delivering drugs to ease respiratory disease symptoms. In this study, we analyzed the SMI performance in terms of the aerosol's velocity profiles, flow pattern, size distribution, and deposition by employing computational fluid dynamics (CFD) simulations. We modeled two different simplified mouth geometries, idealized mouth (IM), and standard mouth (SM). Three different locations (x = 0, x = 5, and x = 10 mm) for the SMI nozzle orifice were chosen along the mouth cavity centerlines, followed by two different SMI nozzle angles (10 deg and 20 deg) for IM geometry. A flowrate of 30 L/min was applied. The simulation results were evaluated against experimental data. It was found that the SMI could be simulated successfully with a level of error of less than 10%. The inhalation flowrate significantly impacted the aerosol's velocity profile and deposition efficiency on both the IM and SM walls. The lowest particle deposition on the mouth wall occurred when a fixed flowrate (30 L/min) was applied inside both geometries, and the SMI nozzle position moved forward to x = 10 mm from the IM and SM inlets. An increase in the SMI nozzle angle increased particle deposition and decreased the deposition fraction for particles with a diameter above 5 μm inside the IM.

ミストデポジション法を用いて調製した質量イオン化支援剤の物性評価と植物性自然毒の可視化の検討

Herein, physical evaluation of a mass ionization assist agent prepared using mist deposition method and the visualization of natural occurring poisons in plants were investigated. An -cyano-4-hydroxy-cinnamic acid (CHCA) crystal layers were formed on sliced botanical samples deposited on a glass slide for a mass ionization assist agent of matrix assisted laser desorption/ionization(MALDI) imaging. The formed CHCA crystal layer exhibits a homogeneous surface at nozzle temperatures over 200 ℃, and its chemical stability is confirmed via Raman spectroscopy. -chaconine and -solanine in sample were detected as H+ adduct localized around of root in sliced potato sample using MALDI-fourier transform ion cyclotron resonance mass spectrometry and mass spectrometry imaging. Mist deposition method is effective for the mass ionization assist preparation and promising for utilize to visualization of target components in samples.

Evaluation of ultrasonic-atomized rhodamine dye film deposition using an optical waveguide sensor with surface plasmon resonance

A process of an ultrasonic-atomized rhodamine 6 G (R6G) dye film deposition was investigated using an optical waveguide (OWG) sensor with surface plasmon resonance (SPR). The sensor surface was coated with a transparent polyvinylcarbazole (PVK) to adjust the SPR wavelength and separate it from the R6G absorption band. Simultaneous observations of R6G absorption and SPR were conducted, and the relationship between the R6G film thickness and absorption intensity was obtained. Furthermore, the mist deposition, the evaporation of solvent water, and the R6G film formation process were estimated.

Layer formation of 2,5-dihydroxybenzoic acid crystals via mist deposition for mass spectrometry imaging of biological samples

Dihydroxybenzoic acid (DHB) crystal layers were formed via mist deposition. Crystal layers exhibiting whiskers measuring a few hundred micrometers were formed at a nozzle temperature of 200 °C. DHB crystal layers exhibited strong absorbance in the ultra-violet wavelength regions, and Raman spectroscopy confirmed their vibrational property. The lipid component was analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry imaging using a DHB crystal layer as the mass ionization assist agent. Cholesterols, diacylglycerides, and triglycerides were detected as sodium adducts. By preventing heterogeneous co-crystallization with analytes, mass images were clearer than when using the conventional aerosol spray method.

Transport properties and electronic structure of fluorine-doped SnO2 prepared by ultrasonic assisted mist deposition

We have investigated the relationship between the transport properties and electronic states of fluorine-doped tin dioxide (FTO) films prepared by ultrasonic assisted mist deposition. The resistivity of the films has the minimum against F/Sn ratios caused by the saturation of carrier concentration. The core-level and valence band PES spectra revealed that there were fluorine ions with two different chemical states and excess fluorine ions tended to form impurity states in band gap, which would not contribute to the conduction of the films. These spectroscopic results well explain the saturated tendency of the carrier concentration of the FTO films.

One-Step Coating of Full-Coverage CsPbBr3 Thin Films via Mist Deposition for All-Inorganic Perovskite Solar Cells

In this work, one-step coating of CsPbBr3 thin films using the mist deposition method is demonstrated. The CsPbBr3 layer is composed of large grains with an average size of approximately 1.4 μm, an...

Facile catalyst deposition using mists for fluidized-bed production of sub-millimeter-long carbon nanotubes

We developed a facile mist deposition method that yields nanometer-thick catalyst films on ceramic beads using aqueous solution of metal nitrates as a low cost catalyst precursor through two different strategies: (a) using a monolayer of a mixture of Fe(NO3)3 and Al(NO3)3 (Fe + Al) and (b) using a bilayer of Fe(NO3)3 on top of the mixture of Fe(NO3)3 and Al(NO3)3 (Fe/(Fe + Al)). In the fluidized bed, the catalyst precursor films were converted into Fe nanoparticles on an AlOx layer by thermal annealing and CNTs were synthesized by chemical vapor deposition. The yield and specific surface area of the resulting CNTs were strongly influenced by the deposition methods. The bilayer deposition strategy showed an improved controllability in acquiring small catalyst particles at a high density, which obtained high yields of CNTs with large specific surface area. As a result, CNTs of 7.5 nm in diameter, triple-wall on average, and 0.6 mm in length were synthesized by employing the fluidized bed chemical vaper deposition technique, suggesting a new way for the high-yield production of long few-wall CNTs at reasonable cost.

Fabrication of CsPbBr3 Thick Films by Using a Mist Deposition Method for Highly Sensitive X-ray Detection

AbstractX-ray imaging is a valuable technique used for medical imaging and non-destructive inspection of industrial products. However, the radiation may put humans at risk of developing cancer. Consequently, highly sensitive X-ray detectors, which enable X-ray imaging at a low dose rate, are required. Metal halide perovskite materials have demonstrated excellent X-ray detection performance including a high sensitivity owing to their high absorption coefficient, high carrier mobility, and long carrier lifetime. However, perovskite thick films with a large area, which is essential to realize the application of such materials to X-ray imaging devices have not been extensively investigated. To this end, in this study, a polymer is employed as a buffer layer to avoid film exfoliation, which makes it difficult to fabricate perovskite thick films, and a 110-μm-thick CsPbBr3 film is successfully obtained using a scalable solution method. In addition, an X-ray detector based on the CsPbBr3 thick film is fabricated, which demonstrates a sensitivity of 11,840 μC Gyair–1 cm–2. This sensitivity is approximately 600 times higher than that of the existing commercial a-Se X-ray detectors.

Fabrication of (101)-oriented CsPbBr3 thick films with high carrier mobility using a mist deposition method

CsPbBr3 is a promising candidate for highly sensitive flat-panel X-ray detectors due to its excellent optoelectronic properties. Thus, a method of preparing thick CsPbBr3 films (>10 μm) over large areas (>10 × 10 cm2) is required. Herein, we report the fabrication of thick CsPbBr3 films using a scalable mist deposition method. In this method, the film thickness was controlled and up-scaled by the number of deposition cycles. The obtained CsPbBr3 films were composed of highly (101)-oriented columnar crystals and had a high carrier mobility of 13 cm2 V−1 s−1, which is comparable to that for single crystals.

Performance of Single-Crystal Silicon Solar Cells With Mist-Deposited Nanocrystalline Quantum Dot Downshifting Films

The paper is concerned with an investigation of the effect of the mist-deposited downshifting nanocrystalline quantum dots (NQD) films both continuous and patterned on the performance of single-crystal commercial silicon solar cells. Different thicknesses of the NQD films are explored in an attempt to improve cell's efficiency in the ultraviolet (UV) range (below 400 nm) of the solar spectrum. The results obtained indicate that the maximum UV absorption is observed with a 50-nm-thick NQD film as reflected by on the average 45% increase in UV external quantum efficiency as compared with the solar cell without the NQD film. The patterned NQD films are showing improved performance in the visible range as compared with unpatterned NQD films without compromising the performance of the cell in the UV range of the solar spectrum. Also, an increase in power conversion efficiency by 12.5% is observed. Overall, an improvement of silicon solar cells performance using mist deposition of downshifting NQD films instead of spin-on coating as previously explored in other studies is demonstrated.

Chemical mist deposition of organic for efficient front- and back-PEDOT:PSS/crystalline Si heterojunction solar cells

We have investigated an n-type crystalline Si (n-Si) heterojunction solar cell with organic conductive polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) on a plane and isotropically textured n-Si substrate by using chemical mist deposition (CMD). The PEDOT:PSS layer was deposited uniformly on isotropically textured n-Si with the increased passivation of surface defects of n-Si and stronger adhesion rather than the spin-coated film by adjusting deposition parameters. The power conversion efficiency increased from 12.5% on plane n-Si to 16%–18.2% for both CMD coated front- and back-PEDOT:PSS/n-Si junction solar cells on the 2 × 2 cm2-sized isotropically textured substrate by combining with a 1–2-nm-thick Ba(OH)2 by CMD as a hole-blocking layer at the Al/n-Si interface. These findings originate from the increased passivation of surface dangling bonds of isotropically textured n-Si, resulting in strong inversion of the n-Si surface to p-type Si by the polymer.

ミストデポジション法による酸化マグネシウム(MgO)薄膜作製 : 大気圧下、低温成長への挑戦(発光型/非発光型ディスプレイ合同研究会)

ミストデポジション法による酸化マグネシウム(MgO)薄膜作製 : 大気圧下、低温成長への挑戦(発光型/非発光型ディスプレイ合同研究会)

Surface potential measurement of n-type organic semiconductor thin films by mist deposition via Kelvin probe microscopy

We partially deposited fullerene (C60) and phenyl-C61-butyric acid methyl ester thin films that are typical n-type semiconductor materials on indium–tin oxide by mist deposition at various substrate temperatures. The topographic and surface potential images were observed via dynamic force microscopy/Kelvin probe force microscopy with the frequency modulation detection method. We proved that the area where a thin film is deposited depends on the substrate temperature during deposition from the topographic images. It was also found that the surface potential depends on the substrate temperature from the surface potential images.

Fluorescence Microscopy Characterization of Patterned Nano-Crystalline Quantum Dot Films

This experiment is a continuation of the study concerned with the lift-off based patterning of nanocrystaline quantum dot (NQD) films [1]. The ultra-thin films formed using colloidal solutions of nanocrystalline quantum dots show good promise in display/LED, as well as nano-labeling applications between others. Regardless of application, to become a part of the functional device the NQD film must be patterned accordingly. Following on the experiments demonstrating effectiveness of the lift-off process in patterning NQD films with resolution down to 1 µm [1] further investigation of the performance of the proposed patterning scheme needed to be carried out. The goal of this contribution is to study uniformity of surface coverage with lift-off patterned NQD films by means of fluorescence microscopy. When exposed to UV light the NQDs feature high photoluminescence with intensity depending on the dots size. The fluorescence microscopy allows capturing the intensity to obtain information about the NQD film uniformity. As a result, using images obtained by means of fluorescence microscopy and employing dedicated image processing tools information regarding film uniformity, pattern definition accuracy, and average intensity can be derived. Also, the fluorescence image can be transferred into grey scale to study its histogram plot and get information about intensity distribution across the NQD patterns. In this study silicon wafers used as substrates are first covered by spin coating with a layer of positive 1805 photoresist to the thickness of about 420 nm and then cured at 100oC. The resist covered wafers were subsequently exposed through the standard Cr-photomask in an aligner/exposure and developed in photoresist developer (351) to create the required patterns [1]. After that, NQDs were blanked deposited using mist deposition technique. The NQD deposited were CdSe/ZnS core/shell featuring average diameter of 6.5 nm and corresponding red (620 nm) emission wavelength. Then, the photoresist removal performed using either dry or wet lift-off. The dry lift-off applied using O2 plasma system and the wet lift-off used acetone dissolution [2]. Figure 1 demonstrates the fluorescence image for NQD patterned film and its intensity distribution. The intensity analysis of the patterns after the lift-off process is considered in terms of an average intensity. The results obtained in this study give further insights into the process of lift-off patterning of nano-crytalline quantum dot films and demonstrate feasibility of the proposed approach. In the full account of this work a complete set of experimental results obtained in the course of this investigation is presented and more detailed analysis of fluorescence images provided.

Effect of substrate bias on mist deposition of conjugated polymer on textured crystalline‐Si for efficient c‐Si/organic heterojunction solar cells

We investigated the chemical mist deposition (CMD) of poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) on textured crystalline silicon (c‐Si) substrate for efficient c‐Si/PEDOT:PSS heterojunction solar cells. The Mie scattering observation and differential mobility analysis characterization revealed that the average size of mist particle decreased from 330 to 30–40 nm with increasing the number density and traveling velocity of mist precursor when positive dc bias of 10 kV was applied to the c‐Si substrate. The uniform deposition of PEDOT:PSS films was performed on textured c‐Si with the increased adhesion by suitably adjusting Vs and substrate temperature. A power conversion efficiency (PCE) of 11.57% was obtained with Jsc of 36.1 mA cm−2, Voc of 0.49 V, and FF of 0.66, when a positive Vs of 10 kV was applied to c‐Si substrate. Furthermore, PCE increased to 12.5% with Jsc of 35.6 mA cm−2, Voc of 0.53 V, and FF of 0.67 by adding a 20‐nm‐thick AR coating layer of molybdenum oxide MoOx (refractive index, n = 2.1) fabricated by CMD using 12 molybdo(VI) phosphoric acid n‐hydrate [H3(PMo12O40) · nH2O] as a precursor. These findings imply that CMD using negatively charged mist precursor is a possible method for the uniform deposition of PEDOT:PSS on textured c‐Si substrate for efficient c‐Si/PEDOT:PSS heterojunction solar cells.