Tunable Bragg stacks from sol-gel derived Ta2O5 and MEL zeolite films

In this paper we investigated sol-gel derived Ta2O5 and nanosized MEL zeolite films obtained by spin coating of Tantalum sol and colloidal zeolite solution, respectively. Refractive index and thickness of the films were determined using non-linear curve fitting of measured reflectance spectra. The influence of the post deposition annealing on the optical properties and thickness of the films was studied. Besides tunable Bragg stacks were designed and prepared by layer-by-layer deposition of Ta2O5 and MEL suspensions with quarter-wave thicknesses. The influence of water, acetone and methanol on the optical behavior of Bragg stacks was discussed.

[1]  S. Mintova,et al.  Nanoporous materials with enhanced hydrophilicity and high water sorption capacity , 2008 .

[2]  F. J. López-Alcaraz,et al.  Nanoparticle-based One-dimensional Photonic Crystals , 2022 .

[3]  Georg von Freymann,et al.  Mesoporous bragg stack color tunable sensors. , 2006, Nano letters.

[4]  Carl M. Lampert,et al.  Structural and optical properties of sol-gel deposited proton conducting Ta2O5 films , 1997 .

[5]  Svetlana Mintova,et al.  Variation of the Si/Al ratio in nanosized zeolite Beta crystals , 2006 .

[6]  A Knoesen,et al.  Solgel derived tantalum pentoxide films as ultraviolet antireflective coatings for silicon. , 1989, Applied optics.

[7]  F. Tepehan,et al.  Optical properties of Ta2O5 thin films deposited using the spin coating process , 1997 .

[8]  Yuhan Sun,et al.  Sol-gel chemistry of tantala HR coatings: Structure and laser-damage resistance , 1997 .

[9]  Avelino Corma,et al.  Inorganic molecular sieves: Preparation, modification and industrial application in catalytic processes , 2011 .

[10]  Nikolay Petkov,et al.  Transformation of amorphous silica colloids to nanosized MEL zeolite , 2001 .

[11]  Thomas F. Coleman,et al.  An Interior Trust Region Approach for Nonlinear Minimization Subject to Bounds , 1993, SIAM J. Optim..

[12]  F. Tepehan,et al.  Optical properties of sol–gel dip-coated Ta2O5 films for electrochromic applications , 1999 .

[13]  Heat treatment effects on the optical properties of Sol–gel Ta2O5 thin films , 1999 .

[14]  Vincent Toal,et al.  Optical properties of silica MFI doped acrylamide-based photopolymer , 2009 .

[15]  E. Seebauer,et al.  Synthesis and characterization of polyvinylpyrrolidine assisted tantalum pentoxide films , 2008 .

[16]  M. Oubaha,et al.  Optical Properties Of High Refractive Index Thin Films Processed At Low-Temperature , 2012 .

[17]  T. Babeva,et al.  Nanosized MEL zeolite and GeSe2 chalcogenide layers as functional building blocks of tunable Bragg stacks , 2012 .

[18]  M. DiDomenico,et al.  Behavior of the Electronic Dielectric Constant in Covalent and Ionic Materials , 1971 .