Room-Temperature Detection of Perfluoroisobutyronitrile with SnO₂/Ti₃C₂T_x Gas Sensors

Abstract

Ti 3 C 2 T x MXene is an emerging two-dimensional transition-metal carbide/nitride with excellent properties of large specific surface and high carrier mobility for room-temperature gas sensing. However, achieving high sensitivity and long-term stability of pristine Ti 3 C 2 T x -based gas sensors remains challenging. SnO 2 is a typical semiconductor metal oxide with high reaction activity and stable chemical properties ideal for a dopant that can comprehensively improve sensing performance. Ti 3 C 2 T x and SnO 2 are investigated for the first time in this study as functional materials for hybridization and room-temperature detection of the gas insulating medium fluorinated nitrile (C 4 F 7 N) with microtoxicity. A Ti 3 C 2 T x −SnO 2 nanocomposite sensor exhibits superior sensitivity, high selectivity, strong anti-interference ability, and excellent long-term stability. The enhanced sensing mechanism is ascribed to the synergistic effect between SnO 2 and Ti 3 C 2 T x and the strong adsorption ability of SnO 2 to C 4 F 7 N similar to bait for fish. We also established an actual leakage scene and demonstrated the feasibility of the Ti 3 C 2 T x −SnO 2 sensor to provide distribution rules with high sensing efficiency for actual engineering applications. The results of this work can expand the gas sensing application of Ti 3 C 2 T x MXene and provide a reference for maintaining C 4 F 7 N-based eco-friendly gas-insulated equipment.

V2CTX MXene-based hybrid sensor with high selectivity and ppb-level detection for acetone at room temperature

“…8d. Thus, the sensing mechanism can be explained by the dominant nature of the electron concentration, which was likely related to the suppression of charge-carrier recombination; hence, low charge carriers resulted in lower resistance 45,60 . Upon exposure to the acetone vapor, the pre-adsorbed oxygen species react with acetone molecules to release trapped electrons (Fig.…”

Design of Ti3C2Tx/SnO2-Selective Ethanolamine Sensor

“…As shown in Figure 8, the gas-sensing mechanism of Ti 3 C 2 T x / SnO 2 composite nanostructure can be explained based on the gas adsorption-desorption characteristics, the charge transfer in heterogeneous semiconductors, and the surface chemical reactions. 38 When Ti 3 C 2 T x /SnO 2 is exposed to air, oxygen molecules are adsorbed on the surface of the Ti 3 C 2 T x /SnO 2 composites. Chemisorbed oxygen traps electrons in the conduction band of Ti 3 C 2 T x /SnO 2 to form oxygen anions (O − , O 2 − ), which leads to the depletion layers in semiconductors and elevated resistance.…”

“…The microprocess results in an increase in carrier concentration and a decrease in resistance. The detailed reactions are as eqs and : O 2 + e − → 2 O − 0.25em or 0.25em O 2 − C 2 H 7 NO + 3 O 2 − ( or 6 normalO − ) → NH 2 OH + 2 CO 2 + 2 H 2 normalO + 6 e − …”

Au/α-Fe2O3/Ti3C2Tx MXene Nanosheet Heterojunctions for High-Performance NH3 Gas Detection at Room Temperature

“…In Figure S1, pure MXene possesses much lower resistance, and the MXene-based sensors show a p-type response, which is in agreement with the results in the literature. 48,49 Additionally, the response/recovery time of Au/ α-Fe 2 O 3 /Ti 3 C 2 T x MXene devices to 5 ppm NH 3 were evaluated to be 3 and 2 s, separately, suggesting that it is a high-performance ultra-fast NH 3 gas detection equipment. Gas-sensing selectivity is one of the key indicators used to judge the properties of gas-sensitive materials.…”