Nanostructured TiO2 Layers for Photovoltaic and Gas Sensing Applications

Abstract

Titanium dioxide (TiO 2 ) has been an important material for decades, combining numerous attractive properties in terms of economy (low price, large availability) or ecology (nontoxic), as well as broad physical and chemical possibilities. In the last few years, the development of nanotechnologies offered new opportunities, not only in an academic perspective but also with a view to many applications with particular reference to the environment. This chapter focuses on the many ways that allow to tailor and organize TiO 2 crystallites at the nanometre scale to make the most of this amazing material in the field of photovoltaics and gas sensing.

A Formaldehyde Sensor Based on Molecularly-Imprinted Polymer on a TiO2 Nanotube Array

“…There are various techniques for synthesizing the MIP layers: electropolymerization [ 38 ], spin coating [ 39 ], and laser deposition [ 40 ]. In this work, we synthesize the PPy-based MIP layer on the TiO 2 -NTA/Ti sheet by direct electropolymerization [ 41 ]. As shown in Figure 1 b, the electropolymerization is carried out in a solution of 50 mL acetonitrile, 0.614 g sodium perchlorate, 0.17 g sodium dodecylsulfate, 0.335 g pyrrole, 55 mg pyrrole-3 carboxylic acid, and 10 mL HCHO (37% in water).…”

Fabrication and Characterization of Titanium Dioxide (TiO2) Nanorods and Nanoflowers on Fluorine Doped Tin Oxide (FTO) for Ethanol Gas Sensor Application

“…The device that has been modified (doped TiO 2 ) showed higher sensitivity compared to the unmodified (undoped TiO 2 ) device. Other than that, activation energy such as heating at a higher temperature (300 o C -500 o C) and exposed the device to UV light is needed to increase the sensitivity towards the gas [26]. Otherwise, the response towards the gas become slow, or there will be no response recorded.…”

“…The time exposure of the vapor had an interval of two minutes, and the readings were recorded for 14 times for each session. When TiO 2 nanostructures exposed to certain gasses, the detection principle was needed during the process [26]. Moreover, if the reaction between gas and nanostructures were strong or chemisorption, free-electron will transfer between the nanostructures while absorbed species will take place.…”

Advanced Nanostructured Coatings Based on Doped TiO2 for Various Applications

“…The substrate material, especially for the electrolytic deposition of TiO 2 . The main problem is the side reaction of water oxidation occurring at the substrate-electrolyte interface, releasing oxygen [132]. -…”