Chemical sensors based on SnO2 and WO3 for the detection of formaldehyde: cooperative effects

First-Principles Study of Formaldehyde Adsorption on TiO2 Rutile (110) and Anatase (001) Surfaces

“…Metal oxide semiconductor gas sensors are quite promising for detection of toxic gas species due to their simple working principle, portability, high sensitivity, and low cost. ,− For HCHO detection, various forms of metal oxides, such as SnO 2 or doped SnO 2 , , WO 3 , NiO thin film, , CdO-mixed In 2 O 3 , and doped ZnO, have been investigated in the past. These sensors have good sensitivity to detect parts per million (ppm) or sub-ppm levels of HCHO and have the potential to be employed in real situations.…”

“…These sensors have good sensitivity to detect parts per million (ppm) or sub-ppm levels of HCHO and have the potential to be employed in real situations. However, one of the obvious disadvantages is that they work at elevated temperatures, usually around 200–400 °C, ,− and require a heater integrated with the sensor. This makes the sensor design more complicated and expensive, further raising the operating cost.…”

Semiconducting Metal Oxide Based Sensors for Selective Gas Pollutant Detection

“…It has been noted that the mode of deposition of thin tin based oxide films highly influenced their physical, electrical, and chemical properties [ 207 , 209 , 212 - 214 , 234 ]. For example, SnO 2 –In 2 O 3 nanocomposites fabricated with a coprecipitation method achieved superb response to ethanol by tuning the content of indium [ 209 ].…”

A Room-Temperature Operation Formaldehyde Sensing Material Printed Using Blends of Reduced Graphene Oxide and Poly(methyl methacrylate)

“…Different methods such as chromatography [ 13 ], spectrophotometry [ 14 ], differential optical absorption spectroscopy (DOAS), Fourier transform infrared absorption, and laser induced fluorescence spectroscopy (LIFS), have been developed for monitoring formaldehyde. For small-size and real-time monitoring devices, in addition, many microscale gaseous formaldehyde detection systems [ 15 ] and various metal oxide semiconductor materials, such as SnO 2 [ 16 , 17 , 18 ], doped ZnO [ 19 , 20 , 21 ], CdO/In 2 O 3 [ 22 ], and nanostructured materials [ 23 ] were also investigated. These sensing technologies offer good sensitivity to formaldehyde, however, most of them require bulky and expensive equipment.…”