Titania Photonic Crystals with Precise Photonic Band Gap Position via Anodizing with Voltage versus Optical Path Length Modulation

• Published in: Nanomaterials (Basel, Switzerland) Vol. 9; no. 4; p. 651
• Main Authors: Ermolaev, Georgy A, Kushnir, Sergey E, Sapoletova, Nina A, Napolskii, Kirill S
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 23-04-2019; MDPI
• Subjects: anodic titanium oxide; Anodizing; Crystals; Dependence; effective refractive index; Electric potential; Electrolytes; Etching; Optoelectronics; photonic band gap; Photonic band gaps; Photonic crystals; Photonics; Photovoltaic cells; porous film; Refractivity; Solar cells; Titanium; Titanium dioxide; Titanium oxide; Titanium oxides; Visible spectrum; Voltage; United States > US; Russia; porous film; anodic titanium oxide; photonic crystals; effective refractive index; anodizing; photonic band gap
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano9040651

Photonic crystals based on titanium oxide are promising for optoelectronic applications, for example as components of solar cells and photodetectors. These materials attract great research attention because of the high refractive index of TiO
. One of the promising routes to prepare photonic crystals based on titanium oxide is titanium anodizing at periodically changing voltage or current. However, precise control of the photonic band gap position in anodic titania films is a challenge. To solve this problem, systematic data on the effective refractive index of the porous anodic titanium oxide are required. In this research, we determine quantitatively the dependence of the effective refractive index of porous anodic titanium oxide on the anodizing regime and develop a model which allows one to predict and, therefore, control photonic band gap position in the visible spectrum range with an accuracy better than 98.5%. The prospects of anodic titania photonic crystals implementation as refractive index sensors are demonstrated.