Porous silicon-VO2 based hybrids as possible optical temperature sensor: Wavelength-dependent optical switching from visible to near-infrared range

Abstract

Morphological properties of thermochromic VO2—porous silicon based hybrids reveal the growth of well-crystalized nanometer-scale features of VO2 as compared with typical submicron granular structure obtained in thin films deposited on flat substrates. Structural characterization performed as a function of temperature via grazing incidence X-ray diffraction and micro-Raman demonstrate reversible semiconductor-metal transition of the hybrid, changing from a low-temperature monoclinic VO2(M) to a high-temperature tetragonal rutile VO2(R) crystalline structure, coupled with a decrease in phase transition temperature. Effective optical response studied in terms of red/blue shift of the reflectance spectra results in a wavelength-dependent optical switching with temperature. As compared to VO2 film over crystalline silicon substrate, the hybrid structure is found to demonstrate up to 3-fold increase in the change of reflectivity with temperature, an enlarged hysteresis loop and a wider operational window for its potential application as an optical temperature sensor. Such silicon based hybrids represent an exciting class of functional materials to display thermally triggered optical switching culminated by the characteristics of each of the constituent blocks as well as device compatibility with standard integrated circuit technology.

Nanosilicon-Based Composites for (Bio)sensing Applications: Current Status, Advantages, and Perspectives

“…), which play a crucial role for the effective detection of (bio)molecules. Mainly, MOx nanolayers/nanoparticles can be deposited over a nano-Si surface through the following techniques: (i) RF and DC magnetron sputtering [24,34,36,37,120,121,123,124,125,126]; (ii) sol–gel/hydrothermal synthesis + spin coating [17,26,127,128,129,130,131]; (iii) drop casting technique + pulsed laser ablation in liquid [132]; (iv) vapor–liquid–solid growth and chemical vapor deposition [25,40,133]; (v) catalytic immersion method [134]; and (vi) electrochemical and chemical deposition [35,122,135].…”

Low-Frequency Dielectric Relaxation in Structures Based on Macroporous Silicon with Meso-Macroporous Skin-Layer

“…These materials are finding their application both independently and often as the 3D matrix media for complex multiphase compositions on their basis. The main areas of application of hierarchical porous materials and compositions based on them are power engineering (most often porous materials are used as electrodes of Li-ion batteries and fuel cells) [ 3 , 4 , 7 , 8 , 9 , 10 ], sensorics and biosensorics [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ], catalysis [ 19 , 20 , 21 ], biotechnology, targeted drug delivery, and theranostics [ 20 , 21 , 22 , 23 , 24 , 25 ]. Another very promising area of application of such materials is bioelectronics, the element base for flexible wearable electronics [ 26 , 27 , 28 , 29 , 30 , 31 ].…”

Optical properties of electrochemically etched N-type silicon wafers for solar cell applications

“…In this work we present optical properties of samples prepared by electrochemical etching method. The result of the electrochemical etching method is in most cases a porous structure, which currently belongs to the materials with a wide range of industrial applications (sensors, as anodes in Lithium-ion battery, photovoltaic applications, biosensors, drug delivery, optoelectronics, self-cleaning coatings, etc) [9][10][11][12][13][14][15][16][17][18][19][20]. It is important to note that homogeneous porous structures do not have a sufficiently low reflectivity and are therefore not suitable for photovoltaic applications.…”