Applications of Spray Coating in Fabrication of Thin Film Devices and Coatings

A special issue of Coatings (ISSN 2079-6412).

Deadline for manuscript submissions: closed (20 September 2017) | Viewed by 36283

Special Issue Editor


E-Mail Website
Guest Editor
University of Michigan-Shanghai Jiao Tong University Joint Institute, 800 Dong Chuan Road, Shanghai 200240, China
Interests: spray technology; particle technology; thin film devices; photovoltaics

Special Issue Information

Dear Colleagues,

Atomization and spray systems have numerous industrial applications from fire sprinklers to supersonic jet engines. One of the applications of spray technology is the fabrication of coatings and thin films. In addition to its conventional coating applications, spray technology has found new applications, owing to the development of new materials and devices, such as solution-processed organic and polymeric materials and thin film optoelectronic thin film devices. The low processing cost at atmospheric pressure, inexpensive equipment, and roll-to-roll compatibility, make spray coating as a viable method for the fabrication of coatings and thin films with large areas. Therefore, this Special Issue of Coatings is devoted to research and review articles on existing and emerging applications of spray coating and deposition. The journal is managed by professional editoral staff and is indexed in Science Citation Index and Web of Science and is tracked for Impact Factor.

In summary, the topics of interest include but are not limited to:

  • Droplet dynamics, evaporation and surface science associated with spray coating
  • Stability, wetting/dewetting and charactrics of spray-on thin films
  • Novel spray nozzles and strategies in spray coating
  • Spray pyrolysis for the fabrication of ceramic thin films
  • Spray coating for the fabrication of inorganic thin films
  • Spray coating for the fabrication of thin film transistors, memroies, organic LED and other similar thin film devices
  • Spray coating in photolovatics: Polymeric, perovskite, quantum-dot, kesterite, and calcophrite solar cells
  • Electrospray coating and electrospinning
  • Spray painting and other conventional applications of spray technology

Prof. Dr. Morteza Eslamian
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Coatings is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Published Papers (5 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

24128 KiB  
Article
Plasma-Sprayed LSM Protective Coating on Metallic Interconnect of SOFC
by Jia-Wei Chen, Kui-Yi Lin, Yung-Chin Yang and Shu-Tuan Yeh
Coatings 2017, 7(12), 226; https://doi.org/10.3390/coatings7120226 - 11 Dec 2017
Cited by 12 | Viewed by 5619
Abstract
In this study, a (La0.8Sr0.2)0.98MnO3 protective layer was prepared on the C276, Crofer22 APU, SUS304, and SUS430 alloys by the atmospheric plasma spraying technique (APS). The oxidation behavior and electrical property of these metal alloys have [...] Read more.
In this study, a (La0.8Sr0.2)0.98MnO3 protective layer was prepared on the C276, Crofer22 APU, SUS304, and SUS430 alloys by the atmospheric plasma spraying technique (APS). The oxidation behavior and electrical property of these metal alloys have been investigated isothermally at 800 °C in air for up to 300 h. Results showed that the ferritic steels transform into MnCr2O4 spinels and a Cr2O3 layer during isothermal oxidation. The C276 alloy formed NiCr2O4 and FeCr2O4 layers; these are protective and act as an effective barrier against chromium migration into the outer oxide layer, and the alloy demonstrated good oxidation resistance and a reasonable match to the coefficient of thermal expansion of the substrate and a low-oxide scale area-specific resistance. The ASR effects on the formation of oxide scale have been investigated, and the ASR of coated samples was below 0.024 Ω·cm2. It has good electrical conductivity for SOFC in long-term use. Full article
Show Figures

Figure 1

2950 KiB  
Article
Surface Roughness Reduction of Additive Manufactured Products by Applying a Functional Coating Using Ultrasonic Spray Coating
by Sam Slegers, Mathias Linzas, Jeroen Drijkoningen, Jan D’Haen, Naveen Krishna Reddy and Wim Deferme
Coatings 2017, 7(12), 208; https://doi.org/10.3390/coatings7120208 - 23 Nov 2017
Cited by 19 | Viewed by 9407
Abstract
To reduce the high surface roughness of additive manufactured (AM) products, typically a post-treatment is required. Subtractive post-treatments are often performed by hand and are therefore expensive and time consuming, whereas conventional additive post-treatments, such as pneumatic spray coating, require large quantities of [...] Read more.
To reduce the high surface roughness of additive manufactured (AM) products, typically a post-treatment is required. Subtractive post-treatments are often performed by hand and are therefore expensive and time consuming, whereas conventional additive post-treatments, such as pneumatic spray coating, require large quantities of coating material. Ultrasonic spray coating, in contrast, is an additive post-treatment technology capable of applying coatings in an efficient way, resulting in less material usage. In this paper, we investigate the application of the ultrasonic spray coating process and the final properties of the coated AM part by applying a thin coating to reduce surface roughness of the AM substrate and to impart hydrophobic functionality. The hydrophobic coating is applied onto flat selective laser sintered (SLS) surfaces prepared from polyamide 12 (PA12) having a surface roughness of Ra = 20 µm. The hydrophobic coating consists of 5 wt % polyvinylidene fluoride (PVDF) in acetone. The coated substrates are analyzed for roughness using a profilometer, a contact angle using a goniometer, and a coating uniformity and thickness using light and scanning electron microscopes. The layer formation applying the ultrasonic spray coating is studied and compared with layer formation using pneumatic spray coating. It is found that a roughness reduction down to 5 µm was achieved via an ultrasonic spray coating with 30 layers of PVDF solution. It is shown in cross-section electron microscopy pictures that, due to the nature of the ultrasonically generated droplets, the rough and porous surface of the SLS surface is filled with the PVDF material after which the roughness is reduced by adding a thin layer on top. In comparison to a standard industry-applied pneumatic spray coating process, the results obtained from ultrasonic spray coating show less material usage, a reduced roughness, and a better filling of the pores, obviously resulting in optimized adhesion. Full article
Show Figures

Figure 1

2787 KiB  
Article
Effect of Microstructure on the Thermal Conductivity of Plasma Sprayed Y2O3 Stabilized Zirconia (8% YSZ)
by Ningning Hu, Matiullah Khan, Yongzhe Wang, Xuemei Song, Chucheng Lin, Chengkang Chang and Yi Zeng
Coatings 2017, 7(11), 198; https://doi.org/10.3390/coatings7110198 - 13 Nov 2017
Cited by 24 | Viewed by 4906
Abstract
In this paper, the effect of microstructure on the thermal conductivity of plasma-sprayed Y2O3 stabilized ZrO2 (YSZ) thermal barrier coatings (TBCs) is investigated. Nine freestanding samples deposited on aluminum alloys are studied. Cross-section morphology such as pores, cracks, m-phase [...] Read more.
In this paper, the effect of microstructure on the thermal conductivity of plasma-sprayed Y2O3 stabilized ZrO2 (YSZ) thermal barrier coatings (TBCs) is investigated. Nine freestanding samples deposited on aluminum alloys are studied. Cross-section morphology such as pores, cracks, m-phase content, grain boundary density of the coated samples are examined by scanning electron microscopy (SEM) and electron back-scattered diffraction (EBSD). Multiple linear regressions are used to develop quantitative models that describe the relationship between the particle parameters, m-phase content and features of the microstructure such as porosity, crack-porosity, and the length density of small and big angle-cracks. Moreover, the relationship between the microstructure and thermal conductivity is investigated. Results reveal that the thermal conductivity of the coating is mainly determined by the microstructure and grain boundary density at room temperature (25 °C), and by the length density of big-angle-crack, monoclinic phase content and grain boundary density at high temperature (1200 °C). Full article
Show Figures

Figure 1

8887 KiB  
Article
Effect of Particle Size on the Thermal Shock Resistance of Plasma-Sprayed YSZ Coatings
by Jibo Huang, Weize Wang, Xiang Lu, Doudou Hu, Zhengqu Feng and Tianxu Guo
Coatings 2017, 7(9), 150; https://doi.org/10.3390/coatings7090150 - 19 Sep 2017
Cited by 20 | Viewed by 5053
Abstract
In this study, yttria-stabilized zirconia (YSZ) coatings were deposited by atmospheric plasma spraying (APS) using feedstocks with two different particle sizes. The effect of particle size on the pore structure and failure mechanism of the coatings was investigated. The evolution of the pore [...] Read more.
In this study, yttria-stabilized zirconia (YSZ) coatings were deposited by atmospheric plasma spraying (APS) using feedstocks with two different particle sizes. The effect of particle size on the pore structure and failure mechanism of the coatings was investigated. The evolution of the pore structure of the two kinds of coatings during cyclic thermal shock test was described by quantitative metallography. The influence of pore orientation on the thermal stress of the coating system was analyzed by the finite element method. It was found that the coatings deposited using coarse particles show a high thermal shock life time. The orientation of the pores in the coatings prepared by different particle sizes was different. A structural parameter was proposed to effectively characterize the pore orientation of the coatings. Coatings prepared by coarse YSZ powder tend to form almost the same number of horizontal and vertical pores, while coatings prepared by fine powder tend to form horizontal ones parallel to the direction of the substrate. The simulation results revealed that the vertical pores can reduce the thermal stress in the coating. The results of this investigation are a benefit to the design and integrity of TBCs. Full article
Show Figures

Figure 1

3625 KiB  
Article
Defect-Free Large-Area (25 cm2) Light Absorbing Perovskite Thin Films Made by Spray Coating
by Mehran Habibi, Amin Rahimzadeh, Inas Bennouna and Morteza Eslamian
Coatings 2017, 7(3), 42; https://doi.org/10.3390/coatings7030042 - 12 Mar 2017
Cited by 48 | Viewed by 9084
Abstract
In this work, we report on reproducible fabrication of defect-free large-area mixed halide perovskite (CH3NH3PbI3−xClx) thin films by scalable spray coating with the area of 25 cm2. This is essential for the [...] Read more.
In this work, we report on reproducible fabrication of defect-free large-area mixed halide perovskite (CH3NH3PbI3−xClx) thin films by scalable spray coating with the area of 25 cm2. This is essential for the commercialization of the perovskite solar cell technology. Using an automated spray coater, the film thickness and roughness were optimized by controlling the solution concentration and substrate temperature. For the first time, the surface tension, contact angle, and viscosity of mixed halide perovskite dissolved in dimethylformamide (DMF) are reported as a function of the solution concentration. A low perovskite solution concentration of 10% was selected as an acceptable value to avoid crystallization dewetting. The determined optimum substrate temperature of 150 °C, followed by annealing at 100 °C render the highest perovskite precursor conversion, as well as the highest possible droplet spreading, desired to achieve a continuous thin film. The number of spray passes was also tuned to achieve a fully-covered film, for the condition of the spray nozzle used in this work. This work demonstrates that applying the optimum substrate temperature decreases the standard deviation of the film thickness and roughness, leading to an increase in the quality and reproducibility of the large-area spray-on films. The optimum perovskite solution concentration and the substrate temperature are universally applicable to other spray coating systems. Full article
Show Figures

Figure 1

Back to TopTop