Porous TiO2-Based Gas Sensors for Cyber Chemical Systems to Provide Security and Medical Diagnosis

Abstract

Gas sensors play an important role in our life, providing control and security of technical processes, environment, transportation and healthcare. Consequently, the development of high performance gas sensor devices is the subject of intense research. TiO2, with its excellent physical and chemical properties, is a very attractive material for the fabrication of chemical sensors. Meanwhile, the emerging technologies are focused on the fabrication of more flexible and smart systems for precise monitoring and diagnosis in real-time. The proposed cyber chemical systems in this paper are based on the integration of cyber elements with the chemical sensor devices. These systems may have a crucial effect on the environmental and industrial safety, control of carriage of dangerous goods and medicine. This review highlights the recent developments on fabrication of porous TiO2-based chemical gas sensors for their application in cyber chemical system showing the convenience and feasibility of such a model to provide the security and to perform the diagnostics. The most of reports have demonstrated that the fabrication of doped, mixed and composite structures based on porous TiO2 may drastically improve its sensing performance. In addition, each component has its unique effect on the sensing properties of material.

Year 2020: A Snapshot of the Last Progress in Flexible Printed Gas Sensors

“…This result has been due to extreme low crystallite size of 5.5 nm at the temperature of firing of 650 • C [81,82]. For the other cited materials, ZnO, synthesized in different nanoforms (see Figure 6) has shown great ability to detect acetone at sup ppm level [83], WO 3 , also as solid solution (W,Sn)O 3 to detect NO 2 [84], TiO 2 as detector of VOCs for medical diagnosis [85].…”

Chemical Gas Sensors Studied at SENSOR Lab, Brescia (Italy): From Conventional to Energy-Efficient and Biocompatible Composite Structures

“…The flexibility of the substrates is one of the major breakthroughs in the design of new generation sensor systems and other electronic devices [11][12][13][14][15]. Due to this reason, in our following studies, we obtained gas sensors using flexible Kapton HN®polyimide films (from DuPont™).…”

“…ALD is a template-assisted technique for the synthesis of nanotubular arrays and requires post-processing separation of the obtained tubes from the template [52]. The fabrication of well-ordered metal oxide nanotubes with the homogeneous tube-size distribution over the substrate by the hydrothermal growth method is difficult [15,50]. Instead, the electrochemical anodization method was applied to obtain highly ordered metal oxide nanotubes in ambient conditions without using vacuum techniques [53,54].…”

“…The tubular structures can be prepared on different kinds of substrates for the fabrication of new generation functional devices [55][56][57][58][59]. The detailed description of the anodic formation of metal oxide nanotubes has been reported in previous works [15,53,54].…”

Preparation and characterization of N-doped TiO2/C composite

“…Luka et al declared that the TiO 2 films with anatase phase can be successfully fabricated using atomic layer deposition and post-deposition annealing method [12]. Galstyan et al illustrated the gas-sensors application of TiO 2 fabricated using physical and chemical methods [13]. Ali et al illustrated the preparation methods of TiO 2 including one-step and two-step, and focused on the application of TiO 2 nanofluids in heat transfer [14].…”