Multi-scale structured, superhydrophobic and wide-angle, antireflective coating in the near-infrared region

Camargo, Kelly Cristine; Michels, Alexandre F.; Rodembusch, Fabiano Severo; Horowitz, Flávio

doi:10.1039/c2cc30456b

Cited by 32 publications

(17 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…27 Multifunctional Ormosil Coating. On the basis of above the results and keeping in mind that the gradually increasing refractive index through coating is crucial to achieve broad band antireflection in normal and oblique incidence angles, 34 we designed a three layer coating through the finite difference time domain (FDTD) simulations. The thicknesses and refractive indices of layers were carefully optimized using FDTD simulations, in order to get best antireflective performance.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

Superhydrophobic and Omnidirectional Antireflective Surfaces from Nanostructured Ormosil Colloids

Yıldırım

Khudiyev

Daglar

et al. 2013

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

A large-area superhydrophobic and omnidirectional antireflective nanostructured organically modified silica coating has been designed and prepared. The coating mimics the self-cleaning property of superhydrophobic lotus leaves and omnidirectional broad band antireflectivity of moth compound eyes, simultaneously. Water contact and sliding angles of the coating are around 160°and 10°, respectively. Coating improves the transmittance of the glass substrate around 4%, when coated on a single side of a glass, in visible and near-infrared region at normal incidence angles. At oblique incidence angles (up to 60°) improvement in transmission reaches to around 8%. In addition, coatings are mechanically stable against impact of water droplets from considerable heights. We believe that our inexpensive and durable multifunctional coatings are suitable for stepping out of the laboratory to practical outdoor applications.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 99%

Superhydrophobic and Omnidirectional Antireflective Surfaces from Nanostructured Ormosil Colloids

Yıldırım

Khudiyev

Daglar

et al. 2013

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…This, combined with the diamond transmittance window in the infrared-where wavelengths are much larger than the rough surface structures involved, and thus light scattering is much smaller than otherwise, as previously reported 14 -allows for diamond-based, optical components for infrared transmission systems that are also self-cleaning.…”

Section: Introductionmentioning

confidence: 97%

“…As in previous works, 14,16 the PTFE layer, with thickness around 120 nm, was deposited by thermal physical vapor deposition at a base pressure of 2 × 10 −6 Torr. A quartz microbalance monitor was used for thickness control.…”

Section: Methodsmentioning

confidence: 99%

Nano-microstructured, superhydrophobic, and infrared transparent polytetrafluoroethylene/diamond films

et al. 2013

Self Cite

View full text Add to dashboard Cite

Abstract. A self-assembled polytetrafluoroethylene (PTFE) nanostructure is deposited on microcrystalline diamond (MCD) films, by use of physical and chemical vapor deposition in a two-step process, to produce (fully) superhydrophobic surfaces: high water contact angle (static, 165 AE 2 deg), very low hysteresis (dynamic, ∼4 deg), and associated sliding angle (1 deg 5 0 AE 15 0 ), thus combining the diamond infrared transparency and self-cleaning properties. These are interpreted in light of Wenzel and Cassie-Baxter wetting models, associated with structural microscopy of nano-micro rough PTFE/MCD surfaces, and present a promising perspective for self-cleaning infrared optics applications.

show abstract

“…In order to increase surface roughness, there are two possibilities: the first one is thorough its generation on the substrate, such as by plasma etching [13], chemical etching [14] or embossing [15]; the second is thorough incorporation of a coating on the substrate, such as by electrospinning [16][17][18], chemical vapor deposition [19][20][21][22][23], lithography [24,25], dip coating [26,27], anodic aluminum oxide [9,28] [29,30] or physical vapor deposition (PVD) [15,31]. Hierarchical structures, i.e., with micro-and nanostructure, have been reported for stability of the superhydrophobic condition [24].…”

Section: Introductionmentioning

confidence: 99%

Adjustable, (super)hydrophobicity by e-beam deposition of nanostructured PTFE on textured silicon surfaces

et al. 2015

View full text Add to dashboard Cite

Polytetrafluoroethylene (PTFE)-like films, produced by electron beam (e-beam) deposition, have shown higher hydrophobicity than those deposited by RF sputtering under similar deposition rates. It was found that this results from both surface chemical composition and nano-roughness. X-ray photoelectron spectroscopy measurements revealed that larger moieties of CF 2 and CF 3 groups were present to reduce surface energy in the e-beam deposited films. RF sputtering led to a higher degree of PTFE target fragmentation producing a different perfluorinated film on the Si substrate. Scanning electron microscopy and atomic force microscopy measurements revealed a much larger rms roughness on the film surfaces produced by e-beam (25.13 nm, at 20 mA) than those by RF sputtering (2.42 nm, at 100 W), and allowed a broad power spectrum density analysis with determination of the j B wetting parameter. In addition, the e-beam deposited films presented a linear increase of contact angle with applied electron current in the range under study (5-20 mA). This allows easy water repellency adjustment, up to 159 ± 2°. For a superhydrophobic state with self-cleaning, a micropyramid structure was wet etched on the Si wafer, followed by PTFE deposition, and a very low contact angle (163 ± 2°) and hysteresis was attained (\3°). These first results indicate that e-beam PTFE deposition with adjustable hydrophobicity may become a useful technique for integrated production with present Si microelectronics technology and for Si solar cells.

show abstract

Multi-scale structured, superhydrophobic and wide-angle, antireflective coating in the near-infrared region

Abstract: Superhydrophobic self-cleaning surfaces were produced with simultaneous wide-angle optical transmittance in the near-infrared region and antireflection properties from combination of multi-scale surface topology based on silica nanoparticles, index grading and interference.

Cited by 32 publications

References 28 publications

Superhydrophobic and Omnidirectional Antireflective Surfaces from Nanostructured Ormosil Colloids

Superhydrophobic and Omnidirectional Antireflective Surfaces from Nanostructured Ormosil Colloids

Nano-microstructured, superhydrophobic, and infrared transparent polytetrafluoroethylene/diamond films

Adjustable, (super)hydrophobicity by e-beam deposition of nanostructured PTFE on textured silicon surfaces

Contact Info

Product

Resources

About