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Surface modification of separators with inorganic oxide ceramics such as SiOx, Al2O3, and TiO2 has emerged as a promising strategy to suppress lithium dendrite growth in lithium metal batteries, thereby enhancing safety and extending battery life. However, the binder‐dependent nature of these modifications often leads to increased separator thickness and a heightened risk of detachment during lithium plating, ultimately compromising both battery performance and energy density. In this study, a conformal, ultrathin (≈20 nm) SiOx coating with strong covalent bonding is grown on a porous separator through a liquid polymer‐derived method. Compared to the pristine polyethylene (PE) separators, this SiOx‐co‐PE separator exhibits significantly improved electrolyte wettability, mechanical strength, and thermal stability without any increase in thickness, leading to vastly enhanced cycling stability and dendrite resistance in cells with Li metal anodes. In a practical demonstration, a 402.9 Wh·kg−1 Li‐S pouch cell, with a high sulfur loading of 9 mg cm−2 and a low E/S ratio of 3.3 µL mg−1, is assembled with the SiOx‐co‐PE separator, achieving stable cycling over 70 cycles at 25 °C. [ABSTRACT FROM AUTHOR]

Conformal coatings are used to protect microelectronic circuitry and increasingly optoelectronics and photonics from detrimental effects of the environment, such as moisture, dust, gasses, and mechanical abrasion. The conventional approach to determine the mean time to failure of conformally coated microelectronic components is usually labor-intensive and time-consuming. We recently showed (Shi et al., 2024) that the quasi-optical approach terahertz (THz) time-of-flight tomography (TOFT) could in principle be used to map conformal-coating thickness over a sample of dimensions on the scale of square centimeters. In this study, we employ THz TOFT to characterize several conformal-coating types on microelectronic test samples in a nondestructive and noncontact manner. This study extends previous work on acrylic conformal coatings. THz TOFT is shown to be effective in the thickness characterization of silicone and acrylic conformal coatings, but not nanometric atomic-layer-deposition metal-oxide coating, which is too thin for the technique. [ABSTRACT FROM AUTHOR]

In military, medical, and safety product manufacturing, the cost of every error is extremely high. The implementation of a conformal coating process carries significant risk if conducted without a proven method to check the compatibility of the lacquer and laminate specified in the product. This paper explains a method of material alignment verification based on Pelofsky relations. This straightforward solution allows engineers to evaluate the risk of potential issues with conformal coating protection at an early stage, before major investments are made in the expensive production process. Real-life production results are presented to support this thesis.

Copyright of Problems of Mechatronics. Armament, Aviation, Safety Engineering / Problemy Mechatroniki. Uzbrojenie, lotnictwo, Inżynieria Bezpieczeństwa is the property of Index Copernicus International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this research, high molecular weight hydroxyl-terminated polydimethylsiloxane (PDMS-OH) was successfully synthesized through a hydroxyl condensation reaction. The optimal reaction conditions included a temperature of 110 °C, a reaction time of 4 h, and a catalyst TMAH amount of 0.08 phr. The structure of PDMS-OH was characterized using nuclear magnetic resonance (1H-NMR) spectroscopy. Subsequently, the PDMS-OH was end-capped with methyl orthosilicate (TMOS) to produce PDMS-TMOS, with a capping agent to hydroxyl group molar ratio of 2:1. The structural analysis of PDMS-TMOS was conducted using Fourier transform infrared spectroscopy (FT-IR) and 1H-NMR. The surface drying time for the moisture-curing coating of PDMS-TMOS was found to be 2 h at room temperature and 25 min at 80 ℃, respectively. The addition of MQ resins to the conformal coatings resulted in a tensile strength of 0.0742 MPa and an elongation at break of 212.7% for the formed film. The coating offers advantages such as a straightforward synthesis process, cost-effectiveness, and high reproducibility, thereby potentially broadening its industrial applications. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium batteries (ASSLBs) are promising energy‐storage devices with high energy density and safety. However, the discharge capacity of ASSLBs that use sulfide solid electrolytes (SEs) and Ni‐rich cathode active materials (CAMs) deteriorates significantly during electrochemical cycling. Interfacial coatings between CAM and sulfide SEs are known to effectively alleviate capacity deterioration. Among the various coating materials, lithium phosphate (LPO) was selected and synthesized via atomic layer deposition (ALD). The crystal phase of the LPO thin film irreversibly changed, and the Li‐ion conductivity deteriorated after heat treatment. Additionally, particle ALD (P‐ALD) of LPO was successfully performed to completely passivate the CAM particles. Torque cells with the LPO‐coated CAMs showed excellent capacity retention, whereas the cells without the LPO coating showed a significantly deteriorated discharge capacity with increased internal resistances. The passivation effect of the LPO coating was confirmed by the cross‐sectional images from a FIB and scanning electron microscopy with energy‐dispersive X‐ray spectroscopy (SEM–EDS) dual system. We believe that the study will help us investigate the effects of side reactions between sulfide SEs and CAMs on the performance and stability of P‐ALD. [ABSTRACT FROM AUTHOR]

Islet transplantation is a curative treatment for patients suffering from type 1 diabetes and has the potential to replace current treatment strategies involving the exogenous administration of insulin. Despite this potential, there are many hurdles in achieving successful long‐term graft survival due to autoimmune and foreign body reactions leading to graft rejection coupled with donor shortage and potential adverse effects from the need for long‐term administration of immunosuppressive drugs. As a result, various approaches have been proposed to increase the viability and function of islet grafts during isolation and ex vivo culture with the use of growth factors, hormones, and other therapeutic agents. In addition, other strategies have addressed how to enhance or maintain islet graft performance after implantation with improvements on immunosuppressive drug regimens and the use of biomaterials to encapsulate and protect the cells from graft rejection. This review focuses on the recent advances in strategies to improve islet viability and function with the addition of exogenous compounds and the implementation of conformal coating as a promising tool for immunoprotection of islet transplants. [ABSTRACT FROM AUTHOR]

A large amount of multi-layer ceramic capacitor (MLCC) is mounted inside a printed circuit board (PCB) constituting electronic components. The use of MLCC in electric vehicles and the latest mobile phones is rapidly increasing with the latest technology. Environments in which electronic components are used are becoming more diverse and conformal coatings are being applied to protect mounted components from these environments. In particular, MLCCs in electronic components mainly have voltage applied. They might be used in environments where humidity exists for various reasons. In a humid environment, electrochemical migration (ECM) will occur, with the cathode and anode on the surface of the MLCC encountering each other. This can result in product damage due to a short circuit. In this study, the effects of voltage, NaCl concentration, and distance between electrodes on a non-mount MLCC, surface mount MLCC, and solder pad pattern were evaluated using a water drop test (WDT). Based on the analysis of the effects of the presence of conformal coating, applied voltage, concentration of NaCl, and the distance between electrodes, a mechanism model for ECM behavior in MLCCs was proposed. [ABSTRACT FROM AUTHOR]

As integrated circuits continue to shrink in size, the demand for high‐quality adhesive layers in copper Damascene interconnects has increased. However, tantalum (Ta) films, used as liners, prepared by atomic layer deposition (ALD) from metal halide precursors, are prone to corrosion and exhibit issues such as low film density and unstable performance. In this study, Ta films are successfully fabricated using a plasma‐enhanced ALD (PEALD) process with an organometallic precursor of Ta(NtBu)(NEt2)3 (TBTDET). The study of the growth conditions reveals that introducing 10% Ar in Ar‐H2 mixed gas leads to continuous high‐quality Ta films. The deposited Ta films are free of halogen impurities, which can avoid the detrimental impact on the stability of the Cu interconnects. Although the films contain some carbon and nitrogen impurities, they do not affect the film adhesive properties. Transmission electron microscopy shows that the Ta films are amorphous, and the amorphous Ta films exhibit superior barrier properties. Moreover, highly uniform Ta films can be conformally deposited into narrow interconnect structures using this PEALD process. These findings suggest that the Ta films prepared by the organometallic precursor can offer a promising solution to address the issues related to the halogen elements in the adhesive layer preparation. [ABSTRACT FROM AUTHOR]

A solar-driven photoelectrochemical (PEC) cell is emerging as one of the promising clean hydrogen generation systems. Engineering of semiconductor heterojunctions and surface morphologies of photoelectrodes in a PEC cell has been a primitive approach to boost its performance. This study presents that a molybdenum disulfide (MoS2) nanoflakes photoanode on 3-dimensional (3D) porous carbon spun fabric (CSF) as a substrate effectively enhances hydrogen generations due to sufficiently enlarged surface area. MoS2 is grown on CSFs utilizing a hydrothermal method. Among three different MoS2 coating morphologies depending on the amount of MoS2 precursor and hydrothermal growth time, film shape MoS2 on CSFs had the largest surface area, exhibiting the highest photocurrent density of 26.48 mA/cm2 and the highest applied bias photon-to-current efficiency (ABPE) efficiency of 5.32% at 0.43 VRHE. Furthermore, with a two-step growth method of sputtering and a subsequent hydrothermal coating, continuous TiO2/MoS2 heterojunctions on a porous CSF further promoted the photoelectrochemical performances due to their optimized bandgap alignments. Enlarged surface area, enhanced charge transfer, and utilization of visible light enable a highly efficient MoS2/TiO2/CSF photoanode with a photocurrent density of 33.81 mA/cm2 and an ABPE of 6.97 % at 0.87 VRHE. The hydrogen generation amount of the PEC cell with MoS2/TiO2/CSF photoanode is 225.4 μmol/L after light irradiation of 60 s.

Microparticles have been applied in many areas, ranging from drug delivery, diagnostics, cosmetics, personal care, and the food industry to chemical and catalytic reactions, sensing, and environmental remediation. Coating further provides additional functionality to the microparticles, such as controlled release, surface modification, bio-fouling resistance, stability, protection, etc. In this study, the conformal coating of microparticles with a positively charged polyelectrolyte (polyallylamine hydrochloride, PAH) by utilizing an acoustofluidic microchip was proposed and demonstrated. The multiple laminar streams, including the PAH solution, were formed inside the microchannel, and, under the traveling surface acoustic wave, the microparticles traversed through the streams, where they were coated with PAH. The results showed that the coating of microparticles can be achieved in a rapid fashion via a microfluidic approach compared to that obtained by the batch method. Moreover, the zeta potentials of the microparticles coated via the microfluidic approach were more uniform. For the unfunctionalized microparticles, the charge reversal occurred after coating, and the zeta potential increased as the width of the microchannel or the concentration of the PAH solution increased. As for the carboxylate-conjugated microparticles, the charge reversal again occurred after coating; however, the magnitudes of the zeta potentials were similar when using the microchannels with different widths or different concentrations of PAH solution. [ABSTRACT FROM AUTHOR]

Cosmic Ray Laboratory – TIFR, Ooty, India is operating the largest tracking muon telescope as a component of the GRAPES-3 (Gamma Ray Astronomy PeV EnergieS at phase – 3) experiment. The basic building blocks of the telescope are proportional counters (PRCs), a large number of which are fabricated in-house for the planned expansion of the existing muon telescope to double its area and enhance the solid angle coverage from 2.3 sr to 3.7 sr as well as achieving higher sensitivity for studying space weather and atmospheric phenomena, cosmic ray composition, etc. The existing muon telescope consists of 3712 PRCs, and after the planned expansion which requires an additional 3776 PRCs, the area of the telescope will increase from the present 560 m 2 to 1130 m 2 . Each of the PRCs will need to be individually equipped with front-end electronics for processing the output signals. The output pulses from PRCs are extremely feeble, and their charges are in the order of ∼ 100 pC. The tiny signal has to be isolated from potential sources of noise before its processing. High-performance, ultra-low noise, and cost-effective electronics are designed, developed, and mass-produced in-house for about 8000 channels of PRCs. The quality of data is improved significantly by interfacing the new electronics with PRCs of the existing muon telescope due to improved signal-to-noise (S/N) ratio, and the data acquisition is made effective as a result of multifold improvement achieved by avoiding undesired interruptions in the data. [ABSTRACT FROM AUTHOR]

Beta cell replacement therapies can restore glycemic control to select individuals living with type 1 diabetes. However, the obligation of lifelong immunosuppression restricts cell therapies from replacing exogenous insulin administration. Encapsulation strategies can reduce the inherent adaptive immune response; however, few are successfully translated into clinical testing. Herein, we evaluated if the conformal coating of islets with poly(N-vinylpyrrolidone) (PVPON) and tannic acid (TA) (PVPON/TA) could preserve murine and human islet function while conferring islet allograft protection. In vitro function was evaluated using static glucose-stimulated insulin secretion, oxygen consumption rates, and islet membrane integrity. In vivo function was evaluated by transplanting human islets into diabetic immunodeficient B6.129S7-Rag1tm1Mom/J (Rag-/-) mice. The immunoprotective capacity of the PVPON/TA-coating was assessed by transplanting BALB/c islets into diabetic C57BL/6 mice. Graft function was evaluated by non-fasting blood glucose measurements and glucose tolerance testing. Both coated and non-coated murine and human islets exhibited indistinguishable in vitro potency. PVPON/TA-coated and control human islets were able to restore euglycemia post-transplant. The PVPON/TA-coating as monotherapy and adjuvant to systemic immunosuppression reduced intragraft inflammation and delayed murine allograft rejection. This study demonstrates that PVPON/TA-coated islets may be clinically relevant as they retain their in vitro and in vivo function while modulating post-transplant immune responses. [ABSTRACT FROM AUTHOR]

A novel methodology, based on wetting and electromigration, for transporting liquid metal, over long distances, at micro-and nano-scale using a stylus is reported. The mechanism is analogous to a dropper that uses 'suction and release' actions to 'collect and dispense' liquid. In our methodology, a stylus coated with a thin metal film acts like the dropper that collects liquid metal from a reservoir upon application of an electric current, holds the liquid metal via wetting while carrying the liquid metal over large distances away from the reservoir and drops it on the target location by reversing the direction of electric current. Essentially, the working principle of the technique relies on the directionality of electromigration force and adhesive force due to wetting. The working of the technique is demonstrated by using an Au-coated Si micropillar as the stylus, liquid Ga as the liquid metal to be transported, and a Kleindiek-based position micro-manipulator to traverse the stylus from the liquid reservoir to the target location. For demonstrating the potential applications, the technique is utilized for closing a micro-gap by dispensing a minuscule amount of liquid Ga and conformally coating the desired segment of the patterned thin films with liquid Ga. This study confirms the promising potential of the developed technique for reversible, controlled manipulation of liquid metal at small length scales. [ABSTRACT FROM AUTHOR]

With increasing CO2 emission and energy scarcity, electrocatalytic CO2 reduction reaction (CO2RR) offers an attractive solution for CO2 resource utilization using sustainable electrical energy. Ag‐based catalysts with high‐curvature nanoneedle structure exhibit the potential to achieve high CO2RR activity, but suffer from insufficient stability due to the vulnerability of the high‐curvature structure during CO2RR. Herein, the uniform porous Zn conformal coating on high‐curvature dendritic Ag nanoneedles (AgNNs@Zn) by vacuum thermal evaporation is prepared. As the surface sacrificial shell, the dissolution and reconstruction of Zn protect the inner Ag core, thus enhancing the CO2RR stability of AgNNs@Zn. The concentration of Ag+ in the electrolyte after 2 h CO2RR electrolysis markedly reduces from 2.4 ug L−1 in AgNNs to 1.4 ug L−1 in AgNNs@Zn. Moreover, the DFT calculation reveals that the constructed Ag–Zn interfaces can stabilize the *COOH intermediates, which promote the selectivity of CO2 reduction into CO. As a result, the optimized AgNNs@Zn catalyst exhibits the FECO of ≈91% at −0.86 V versus RHE in H‐cell, and FECO of 90% at 100 mA cm−2 above 12 h in flow cell. This work provides a feasible strategy to synthesize bimetallic catalysts with core–shell structure for better CO2RR performance. [ABSTRACT FROM AUTHOR]

The objective of this activity was to develop novel European polyurethane (PU) materials suitable for versatile space applications that can be manufactured via "environmentally friendly" procedure without the use of toxic isocyanates and/or employing sustainable materials sources. The non-isocyanate polyurethanes (NIPUs) were formulated as systems applicable as conformal coatings and potting systems in launcher manufacturing, and thermal insulation foams for use in spacecrafts manufacturing. The study confirmed possibility to prepare non-isocyanate polyurethanes with renewables content minimally 50 wt.% that are competitive to the existing space-qualified polyurethane-based materials. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate how metal-oxide thin-film conformal coatings grown by atomic layer deposition (ALD) can be exploited as an effective approach to mitigate tin whisker growth on printed circuit boards. First, we study the effect of different ALD coatings and process parameters on Sn–Cu-electroplated test coupons, by combining optical imaging and scanning electron microscopy and evaluating whisker distribution on the surface. On these samples, we found that one important parameter in mitigating whisker growth is the time interval between electroplating and the ALD coating process (pre-coat time), which should be kept of the order of few days (2, based on our results). Atomic layer-deposited coatings were also found to be effective toward whisker formation in different storage conditions. Furthermore, we show that ALD coating is also effective in limiting the need for outgassing of electronic assemblies (PCBAs), which is an additional stringent requirement for applications in space industry. Our experimental results thus demonstrated that atomic layer deposition is a suitable technique for aerospace applications, both in terms of degassing and whisker mitigation. [ABSTRACT FROM AUTHOR]

The three-dimensional (3D) structure of batteries nowadays obtains a lot of attention because it provides the electrodes a vast surface area to accommodate and employ more active material, resulting in a notable increase in areal capacity. However, the integration of polymer electrolytes to complicated three-dimensional structures without defects is appealing. This paper presents the creation of a flawless conformal coating for a distinctive 3D-structured NiO/Ni anode using a simple thermal oxidation technique and a polymer electrolyte consisting of three layers of PAN-(PAN-PVA)-PVA with the addition of Al2O3 nanoparticles as nanofillers. Such a composition with a unique combination of polymers demonstrated superior electrode performance. PAN in the polymer matrix provides mechanical stability and corrosion resistance, while PVA contributes to excellent ionic conductivity. As a result, NiO/Ni@PAN-(PAN-PVA)-PVA with 0.5 wt% Al2O3 NPs configuration demonstrated enhanced cycling stability and superior electrochemical performance, reaching 546 mAh g−1 at a 0.1 C rate. [ABSTRACT FROM AUTHOR]

Freestanding networked nanoparticle (NP) films hold substantial potential due to their high surface areas and customizable porosities. However, NPs with high surface energies and heterogeneous sizes or shapes present considerable challenges as they tend to aggregate, compromising their structural integrities. In this study, we report the scalable fabrication of ultrathin, bicontinuous, and densely packed carbon NP films via Pickering emulsion-mediated interfacial assembly. This method enables the efficient transfer of closely packed NP networks from emulsions to air-water interface and ultimately to diverse substrates, which provides broad versatility for tailored applications. Utilizing the jamming structures of NPs at the fluid interface, we achieve precise control over film size with homogeneous thickness while minimizing material waste and facilitating recyclability. Notably, the films can be smoothly transferred to micropatterned, stretchable, and complex three-dimensional substrates, enabling the realization of robust conformal coatings. The resulting films exhibit high structural stability and flexibility, demonstrating significant potential for the design of stretchable and flexible devices.

Graphene is regarded as the best anticorrosion material; however, due to its inherent electrical conductivity, it, instead, greatly promotes galvanic corrosion when added as a filler above a certain loading threshold in a polymer composite coating. Electrically insulating 2D materials such as hexagonal boron nitride (h -BN), which could be alternatives, also fail due to their poor dispersibility/compatibility with the polymer matrix, thus limiting their practical applications. Herein, we report a unique fluorinated graphene (FG), with optimizable F/C and C/O ratios (versatile surface chemistry properties), produced by scalable fluorination of facile and eco-friendly electrochemically exfoliated graphene (ECG, surface properties of which are tunable by varying electrochemical conditions) and propose a one-step and cost-effective fluorination route towards highly polymer matrix compatible composite for electronic passivation; in fact this alloys two steps optimization of surface functionalities leading to required properties of FG and the composite. By tuning and understanding their hydrophobicity, electrical conductivity, extent of fluorination, etc., through molecular dynamics (MD) simulations as well, with just 1% filler loading, the FG-polymer-composite shows the superior anticorrosion performance (corrosion rate (CR) = 7.83 × 10−8 mm/year; current = 3.37 × 10−12 A cm−2). Construction of a robust diffusion barrier indicated by a monotonic decrease in CR with FG loading leads FG to outperform other reported functionalized graphene and BN-related 2D materials. Extension of the use of FG composites to a nonmetallic substrate such as a flexible printed circuit board (PCB) is an original idea, and superior corrosion inhibition is achieved while preventing the risk of electrical short circuits due to the electrical insulating nature and the high breakdown voltage of FG; thus, making it a durable passivation layer on electronic devices, even in harsh environments. This work represents a breakthrough in anticorrosion technology and provides a novel strategy for exploring extremely impermeable composites for the long-term passivation of multi-functionalized electronics. The fluorinated graphene nanocomposite coating exhibit an ultralow corrosion rate and high electrical insulating, which is beneficial for archiving durable electronic passivation. [Display omitted] [ABSTRACT FROM AUTHOR]

Multilayer conformal coatings have been shown to provide a nanoscale barrier between cells and their environment with adequate stability, while regulating the diffusion of nutrition and waste across the cell membrane. The coating method aims to minimize capsule thickness and implant volume while reducing the need for immunosuppressive drugs, making it a promising approach for islet cell encapsulation in clinical islet transplantation for the treatment of Type 1 diabetes. This study introduces an immunoprotective nanocoating obtained through electrostatic interaction between quaternized phosphocholine-chitosan (PC-QCH) and tetrahydropyran triazole phenyl-alginate (TZ-AL) onto mouse β-cell spheroids. First, successful synthesis of the proposed polyelectrolytes was confirmed with physico-chemical characterization. A coating with an average thickness of 540 nm was obtained with self-assembly of 4-bilayers of PC-QCH/TZ-AL onto MIN6 β-cell spheroids. Surface coating of spheroids did not affect cell viability, metabolic activity, or insulin secretion, when compared to non-coated spheroids. The exposure of the polyelectrolytes to THP-1 monocyte-derived macrophages lead to a reduced level of TNF- α secretion and exposure of coated spheroids to RAW264.7 macrophages showed a decreasing trend in the secretion of TNF- α and IL-6. In addition, coated spheroids were able to establish normoglycemia when implanted into diabetic NOD-SCID mice, demonstrating in vivo biocompatibility and cellular function. These results demonstrate the ability of the PC-QCH/TZ-AL conformal coating to mitigate pro-inflammatory responses from macrophages, and thus can be a promising candidate towards nanoencapsulation for cell-based therapy, particularly in type 1 diabetes, where the insulin secreting β-cells are subjected to inflammation and immune cell attack. [Display omitted] [ABSTRACT FROM AUTHOR]

Conformal coatings are widely used on electronic assemblies to protect electronic devices from ionic contaminants, humidity, and dust. This study focused on the influence of the process related no-clean flux residue on the protection performance of three conventionally used conformal coatings under cyclic humidity conditions. A test Printed Circuit Board (PCB) with comb-structure surface insulation resistance (SIR) pattern was used as test vehicle. Two-electrode electrochemical impedance spectroscopy (EIS) was used to monitor the water uptake behavior of the coatings under cyclic thermal-humidity exposure in the air, followed by chrono-amperometry to evaluate the effect of penetrated moisture reaching the PCB surface. Failure modes of the SIR include increased leakage current and degradation product such as electrochemical migration (ECM) between the comb-structure electrodes. The surface morphology and adhesion was inspected using scanning electron microscopy and corrosion product analysis was carried out using energy dispersive spectroscopy. Results suggest that the moisture barrier properties of the coating and adhesion of the coating are important parameters affecting the corrosion protection performance and the presence of no-clean flux residue has most significant influence on the adhesion of the coatings. Among the coatings investigated, elastomeric acrylate showed best performance due to unsurpassed adhesion even under aggressive solder flux contaminated conditions. Two electrode EIS method could differentiate the compatibility of flux residue and conformal coating within few hours. • Three conformal coatings were in-situ tested on the printed circuit board (PCB) in the climatic chamber with electrochemical methods. • Humidity penetrates through the tested conformal coatings and reach to the PCB surface only within few hours. • Adhesion is the key factor for the protection of electrochemical migration induced short circuit. • The compatibility of conformal coating and solder flux play a vital role on the coating adhesion performance on PCB. • Hygroscopic flux residue below conformal coating could accelerate the formation of capillary channels in the coating. [ABSTRACT FROM AUTHOR]

Contractility is one of the most crucial functions of the heart because it is directly related to the maintenance of blood perfusion throughout the body. Both increase and decrease in contractility may cause fatal consequences. Therefore, drug discovery would benefit greatly from reliable testing of candidate molecule effects on contractility capacity. In this study, we further developed a dual-axis piezoelectric force sensor together with our human cell–based vascularized cardiac tissue constructs for cardiac contraction force measurements. The capability to detect drug-induced inotropic effects was tested with a set of known positive and negative inotropic compounds of isoprenaline, milrinone, omecamtiv mecarbil, propranolol, or verapamil in different concentrations. Both positive and negative inotropic effects were measurable, showing that our cardiac contraction force measurement system including a piezoelectric cantilever sensor and a human cell–based cardiac tissue constructs has the potential to be used for testing of inotropic drug effects. [ABSTRACT FROM AUTHOR]

Contractility is one of the most crucial functions of the heart because it is directly related to the maintenance of blood perfusion throughout the body. Both increase and decrease in contractility may cause fatal consequences. Therefore, drug discovery would benefit greatly from reliable testing of candidate molecule effects on contractility capacity. In this study, we further developed a dual-axis piezoelectric force sensor together with our human cell–based vascularized cardiac tissue constructs for cardiac contraction force measurements. The capability to detect drug-induced inotropic effects was tested with a set of known positive and negative inotropic compounds of isoprenaline, milrinone, omecamtiv mecarbil, propranolol, or verapamil in different concentrations. Both positive and negative inotropic effects were measurable, showing that our cardiac contraction force measurement system including a piezoelectric cantilever sensor and a human cell–based cardiac tissue constructs has the potential to be used for testing of inotropic drug effects.

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ga 2 O 3 has emerged as a promising material for the wide-bandgap industry aiming at devices beyond the limits of conventional silicon. Amorphous Ga 2 O 3 is widely being used for flexible electronics, but suffers from very high resistivity. Conventional methods of doping like ion implantation require high temperatures post-processing, thereby limiting their use. Herein, an unconventional method of doping Ga 2 O 3 films with Si, thereby enhancing its electrical properties, is reported. Ion-beam sputtering (500 eV Ar + ) is utilized to nanopattern SiO 2 -coated Si substrate leaving the topmost part rich in elemental Si. This helps in enhancing the carrier conduction by increasing n-type doping of the subsequently coated 5 nm amorphous Ga 2 O 3 films, corroborated by room-temperature resistivity measurement and valence band spectra, respectively, while the nanopatterns formed help in better light management. Finally, as proof of concept, metal-semiconductor-metal (MSM) photoconductor devices fabricated on doped, rippled films show superior properties with responsivity increasing from 6 to 433 mA W -1 while having fast detection speeds of 861 µs/710 µs (rise/fall time) as opposed to non-rippled devices (377 ms/392 ms). The results demonstrate a facile, cost-effective, and large-area method to dope amorphous Ga 2 O 3 films in a bottom-up approach which may be employed for increasing the electrical conductivity of other amorphous oxide semiconductors as well., (© 2024 Wiley‐VCH GmbH.)

The exposure of miniaturized components to the environment leads to new failure analysis as a result of environmental conditions and constant innovation of the component materials and dimensions. Generally, these failures occur on the solder joints, which ensure the mechanical and electrical connection between the printed circuit board and the component. Conformal coating is a thin layer of a polymeric material that encapsulates the components and consequently their solder joints to protect against harsh environments. However, this application is not recommended in some components such as ball grid array and quad flat no-lead (QFN) packages, since it can reduce the reliability of the solder joints when exposed to temperature fluctuations. Therefore, by using a finite element analysis, a thermal cycle test was simulated with and without conformal coating. The simulation output was extrapolated to lifetime theoretical methods with the aim of predicting the number of cycles until the failure of the solder joints. Therefore, this study demonstrates that for both components without conformal coating, solder joint lifetime was a precise approximation. Coated solder joints reveal a drastic reduction in their reliability due to the influence of the conformal coating behavior and its thermomechanical properties. [ABSTRACT FROM AUTHOR]

Charge-transporting layers (CTLs) are important in determining the performance and stability of perovskite solar cells (PSCs). Recently, there has been considerable use of self-assembled monolayers (SAMs) as charge-selective contacts, especially for hole-selective SAMs in inverted PSCs as well as perovskite involving tandem solar cells. The SAM-based charge-selective contact shows many advantages over traditional thin-film organic/inorganic CTLs, including reduced cost, low optical and electric loss, conformal coating on a rough substrate, simple deposition on a large-area substrate and easy modulation of energy levels, molecular dipoles and surface properties. The incorporation of various hole-selective SAMs has resulted in high-efficiency single junction and tandem solar cells. This topical review summarizes both the advantages and challenges of SAM-based charge-selective contacts, and discusses the potential direction for future studies.

Most of the encapsulation films seen in the market use non‐pre‐metered coating technology, like dip coating or spray coating, which is difficult to control the film thickness, has poor film uniformity, low material utilization, and can only be coated on the front side, but cannot be used for three‐dimensional encapsulation. We proposed a silicone B‐stage material with coating and lamination processes, which can greatly reduce the cost of the process, improve the uniformity of film formation, and achieve the conformal coating of micro‐LED. [ABSTRACT FROM AUTHOR]

For application in harsh environmental conditions, printed circuit boards (PCB) are usually coated with a protective polymer typically of a 50-µm thickness that provides electrical insulation. [ABSTRACT FROM AUTHOR]

This review will focus on the controlled release of pharmaceuticals and other organic molecules utilizing polymeric nanolayers grown by initiated chemical vapor deposited (iCVD). The iCVD layers are able conform to the geometry of the underlying substrate, facilitating release from one- and two-dimensional nanostructures with high surface area. The reactors for iCVD film growth can be customized for specific substrate geometries and scaled to large overall dimensions. The absence of surface tension in vapor deposition processes allows the synthesis of pinhole-free layers, even for iCVD layers

Conformal coating (CC) is widely used to protect printed circuit board from corrosion, mold growth, and electrical failures. To ensure effective protection, the thickness of the CC layer needs to be well controlled. However, to date, the coating thickness is usually measured in a destructive way under microscopes. In this paper, we proposed to use optical coherence tomography (OCT) to measure the CC thickness nondestructively. Specifically, to obtain a good accuracy in thickness measurement, we constructed a spectral domain OCT with the ultra-high axial resolution to image the CC layer in three dimensions and developed an image segmentation algorithm to detect the CC layer from the OCT images. Finally, we evaluated the effectiveness of the proposed method by comparing it with the conventional method, and the results demonstrate that the measurement by our method is consistent with that by the microscope. This also indicates that OCT with high axial resolution can potentially be used to measure the CC thickness accurately and nondestructively.

A conformal coating is a protective chemical material that can be applied as a thin layer on printed circuit board assemblies (PCBAs). The purpose of conformal coating is to prevent the interaction between external environmental factors and the electrical assembly. However, since conformal coating materials have different mechanical properties than electronic components, their use may induce additional mechanical stresses on the board. This study focuses on the effect of having a different coefficient of thermal expansion (CTE) for the conformal coating material from the solder joints of ball grid array (BGA) packages on printed circuit boards (PCBs). Typical lead-free solders have a CTE of less than 25 ppm/°C, while coating materials have a much higher CTE. For example, polyurethane has a CTE around 193 ppm/°C. This CTE mismatch generates stresses in different directions on the solder joints, especially when the assembly is subjected to temperature cycling during its service. In this effort, four samples of PCB assemblies that have BGAs were used in temperature cycling tests. The sample size is nine modules, with each module having at least 272 exposed BGA joints. Three of the samples were coated by a layer of polyurethane and one baseline sample was not coated. Coating thickness was selected to be the experimental design factor. Thus, these three samples, which had different thicknesses (30, 80, and $130~\mu \text{m}$), were evaluated and compared against each other and against the noncoated sample. By comparing the four samples, it was found that a thick coating material significantly reduced the lifetime for BGA solder balls by initiating early solder cracks, which propagated and caused complete separation in the solder joint. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) have revolutionized the world of portable power, enabling the proliferation of electronics, electric vehicles, and renewable energy systems. However, these remarkable energy storage devices are not without their challenges, ranging from safety concerns to capacity degradation. Conformal coatings have emerged as a transformative technology to address these issues by providing a protective and uniform layer over critical battery components, such as the anode, cathode, and separator. The innovations in technologies relating to multifunctional conformal coatings have taken their application a step ahead of only providing safety. Multifunctional coatings have enhanced battery performance, developed solid-state battery technology, and allowed 3D and nano-architectured LIBs to be easily fabricated. Materials like conductive polymers, polymer electrolytes, and graphene are leading the research for multifunctional coatings for high-performance LIBs, increasing their conductivity, cycling capacity, and more. This comprehensive review aims to provide a detailed understanding of the recent innovations in the field in the realms of varied materials and methods utilized for the conformal coating of LIBs. [Display omitted] • Materials for conformal coating of Lithium-ion batteries • Characteristics of conformal coatings • Multifunctional conformal coatings for high-performance lithium-ion batteries • Conformal Coatings Techniques [ABSTRACT FROM AUTHOR]

Silver nanowire (AgNW) networks have been intensively investigated in recent years. Thanks to their attractive physical properties in terms of optical transparency and electrical conductivity, as well as their mechanical performance, AgNW networks are promising transparent electrodes (TE) for several devices, such as solar cells, transparent heaters, touch screens or light-emitting devices. However, morphological instabilities, low adhesion to the substrate, surface roughness and ageing issues may limit their broader use and need to be tackled for a successful performance and long working lifetime. The aim of the present work is to highlight efficient strategies to optimize the physical properties of AgNW networks. In order to situate our work in relation to existing literature, we briefly reported recent studies which investigated physical properties of AgNW networks. First, we investigated the optimization of optical transparency and electrical conductivity by comparing two types of AgNWs with different morphologies, including PVP layer and AgNW dimensions. In addition, their response to thermal treatment was deeply investigated. Then, zinc oxide (ZnO) and tin oxide (SnO2) protective films deposited by Atmospheric Pressure Spatial Atomic Layer Deposition (AP-SALD) were compared for one type of AgNW. We clearly demonstrated that coating AgNW networks with these thin oxide layers is an efficient approach to enhance the morphological stability of AgNWs when subjected to thermal stress. Finally, we discussed the main future challenges linked with AgNW networks optimization processes.

Abstract We present a facile and scalable coating method based on controlled airbrushing, which is suitable for conformal resin coating in continuous roll-to-roll (R2R) nanoimprint lithography (NIL) process. By controlling the concentration of UV-curable polymeric resin with mixing the volatile solvent and its airbrushing time, the coated resin film thickness can be readily tuned. After R2R NIL using a flexible nanoscale line pattern (nanograting) mold is conducted upon the airbrushed resin film, a large-area uniform nanograting pattern is fabricated with controlled residual layer thickness (RLT) based on the initial film thickness. We investigate the faithful airbrushing condition that can reliably create the uniform thin films as well as various nanopatterns with controlled morphologies. Using more diluted resin and shorter airbrushing time can reduce the RLTs favourably for many applications, yet is apt to induce the nanoscale pores and discontinued lines. We also discuss how to further improve the quality and scalability of resin airbrushing and its potential applications particularly requiring high-speed and conformal coating on highly topographic and flexible surfaces.

The use of quad flat no-leads (QFNs) in high-reliability applications is receiving increased interest. To address concerns of harsh working environments, conformal coatings are used to protect the components and associated printed circuit board (PCB). However, using conformal coatings can pose a reliability risk for the components on the PCB. This paper details an investigation into the effect of conformal coatings on the reliability of QFN second-level solder interconnections. Five QFN package types and two types of conformal coatings were investigated. In the experiments, a large population of QFN assemblies coated with conformal coatings were subjected to a thermal cycling test condition. These components, designed with daisy-chain connections, were monitored during the thermal cycling tests, and the exact time for failure to occur for each component was recorded and analyzed. Detailed finite-element models for the tested QFN assemblies were developed; the inelastic strain energy density was used as the damage indicator to evaluate the impact of conformal coating on the solder joint reliability. Modeling results reveal that the conformal coating plays an intricate role in QFN solder joint reliability. The presence of conformal coating results in a reduction in the shear stress in the solder joint and plays a positive role in solder reliability. However, it also induces more stress in the solder joint in the out-of-plane direction and plays a negative role. These two mechanisms are competing, and their relative magnitude will determine the overall effect of conformal coating on solder joint reliability. [ABSTRACT FROM AUTHOR]

This paper describes how metal-organic frameworks (MOFs) conformally coated on plasmonic nanoparticle arrays can support exciton-plasmon modes with features resembling strong coupling but that are better understood by a weak coupling model. Thin films of Zn-porphyrin MOFs were assembled by dip coating on arrays of silver nanoparticles (NP@MOF) that sustain surface lattice resonances (SLRs). Coupling of excitons with these lattice plasmons led to an SLR-like mixed mode in both transmission and transient absorption spectra. The spectral position of the mixed mode could be tailored by detuning the SLR in different refractive index environments and by changing the periodicity of the nanoparticle array. Photoluminescence showed mode splitting that can be interpreted as modulation of the exciton line shape by the Fano profile of the surface lattice mode, without requiring Rabi splitting. Compared with pristine Zn-porphyrin, hybrid NP@MOF structures achieved a 16-fold enhancement in emission intensity. Our results establish MOFs as a crystalline molecular emitter material that can couple with plasmonic structures for energy exchange and transfer. [ABSTRACT FROM AUTHOR]

It is appealing to fill up TiO2 nanotube arrays with other semiconductors to form three‐dimensional heterojunctions of interdigitated feature. This benefits from the large interfacial area for rapid charge separation and the ordered vertical channels for oriented charge transport. However, it remains a great challenge to fill the nanotubes with dense films and more importantly in a conformal manner. In this study, the TiO2 nanotubes are conformally filled with ZnS by successive ionic layer adsorption and reaction. The ZnS exists in the form of either discrete nanoparticles or dense films when using nitrate or acetate precursor solutions, respectively. This is attributed to the hydrolysis process of the acetates in aqueous solutions, which releases extra hydroxyl ions beneficial to film formation. The CuS/TiO2 heterojunctions, resulted from ZnS dense films, show better rectifying behaviors in view of the interdigitated structure. Such a conformal filling process with dense films can also be used to form other MxSy/TiO2 bulk heterojunctions toward applications in optoelectronics, photovoltaics, photocatalysis, and so on. TiO2 nanotubes are conformally filled with ZnS, either as discrete nanoparticles or dense films when nitrate or acetate precursor solutions are respectively used. This is attributed to hydrolysis of the acetates in aqueous solution, which releases extra hydroxyl ions that are beneficial to film formation. [ABSTRACT FROM AUTHOR]

Encapsulation of pharmaceutical powders within thin functional polymer films is a powerful and versatile method to modify drug release properties. Conformal coating over the complete surface of the particle via chemical vapor deposition techniques is a challenging task due to the compromised gas–solid contact. In this study, an initiated chemical vapor deposition reactor was adapted with speakers and vibration of particles was achieved by playing AC/DC’s song “Thunderstruck” to overcome the above-mentioned problem. To show the possibilities of this method, two types of powder of very different particle sizes were chosen, magnesium citrate (3–10 µm, cohesive powder) and aspirin (100–500 µm, good flowability), and coated with poly-ethylene-glycol-di-methacrylate. The release curve of coated magnesium citrate powder was retarded compared to uncoated powder. However, neither changing the thickness coating nor vibrating the powder during the deposition had influence on the release parameters, indicating, that cohesive powders cannot be coated conformally. The release of coated aspirin was as well retarded as compared to uncoated aspirin, especially in the case of the powder that vibrated during deposition. We attribute the enhancement of the retarded release to the formation of a conformal coating on the aspirin powder.

In this paper, the compressive stress of pristine and coated vertically-aligned (VA) multi-walled (MW) carbon nanotube (CNT) pillars were investigated using flat-punch nano-indentation. VA-MWCNT pillars of various diameters (30–150 µm) grown by low-pressure chemical vapor deposition on silicon wafer. A conformal brittle coating of niobium-titanium-nitride with high superconductivity temperature was deposited on the VA-MWCNT pillars using atomic layer deposition. The coating together with the pillars could form a superconductive vertical interconnect. The indentation tests showed foam-like behavior of pristine CNTs and ceramic-like fracture of conformal coated CNTs. The compressive strength and the elastic modulus for pristine CNTs could be divided into three regimes of linear elastic, oscillatory plateau, and exponential densification. The elastic modulus of pristine CNTs increased for a smaller pillar diameter. The response of the coated VA-MWCNTs depended on the diffusion depth of the coating in the pillar and their elastic modulus increased with pillar diameter due to the higher sidewall area. Tuning the material properties by conformal coating on various diameter pillars enhanced the mechanical performance and the vertical interconnect access (via) reliability. The results could be useful for quantum computing applications that require high-density superconducting vertical interconnects and reliable operation at reduced temperatures.