SnO₂ Quantum Dots-Functionalized MoO₃ Nanobelts for High-Selectivity Ethylene Sensing

Abstract

Highly selective and sensitive detection of the phytohormone ethylene, especially at low concentrations, is essential for control of plant growth, development, senescence, and fruit ripening. Metal oxide semiconductors exhibit excellent sensing properties due to their excellent physicochemical properties and unique structures. This study developed SnO2 quantum dots (QDs)-functionalized MoO3 nanobelts (NBs) for highly selective and sensitive ethylene detection. The prepared nanocomposite is composed of MoO3 NBs surface loaded with fine SnO2 QDs, and the n-n heterojunction is formed at the interface. Sensing properties of the SnO2 QDs/MoO3 NBs to ethylene are measured, and results reveal that 2.5%-SnO2 QDs/MoO3 NBs exhibited excellent response (100 ppm 40%), low detection limit (500 ppb), and selectivity to ethylene at a low operating temperature (150 °C) compared with pure MoO3 NBs and SnO2 QDs. The enhanced gas-sensing performance is explained based on the modulation of the interface barrier caused by the formation of n-n heterojunctions at the SnO2/MoO3 interface and the synergetic effect of these two materials. This heterojunction indicates that SnO2 QDs/MoO3 NBs are promising sensing materials for the ethylene gas sensor.

Mo2C/MoO3@rGO Ternary Nanocomposites as High-Performance Gas Sensor for Trace NH3 Detection at Room Temperature

“…While the MoO 3 surface loses electrons and forms a depletion layer, increasing the resistance of the material. The surface oxygen ion species of the material are affected by the operating temperature . At room temperature, the absorbed oxygen ion on the surface of the material is mainly O 2 – .…”

“…The surface oxygen ion species of the material are affected by the operating temperature. 60 At room temperature, the absorbed oxygen ion on the surface of the material is mainly O 2 − . A process shown in eqs 3 and 4 demonstrates the gas response process when the sensor is exposed to the reducing gas NH 3 .…”

Conductometric Gas Sensor Based on MoO3 Nanoribbon Modified with rGO Nanosheets for Ethylenediamine Detection at Room Temperature

“…Third, heterogeneous structures are formed between the two materials when MoO 3 is combined with rGO. The work function of the n-type material MoO 3 (5.3 eV) [57] is different from that of the p-type material rGO (4.8 eV) [19]. The electrons in rGO are transferred to MoO 3 to balance the Fermi energy level (Ef), which causes the energy band to bend and increases the electron concentration of MoO 3 in the composite [58].…”

Melamine Cyanaurate Microrods Decorated with SnO2 Quantum Dots for Photoelectrochemical Applications

“…Among these oxides, SnO 2 nanostructures have several industrial applications owing to their high surface area, strong stability, and broad bandgap. Moreover, owing to these superior properties, SnO 2 nanostructures have been widely used in a variety of technological applications, such as batteries, photocatalysis, perovskite solar cells, sensing, and energy conversion [7][8][9][10][11]. Moreover, the catalytic activity of SnO 2 nanostructures is limited owing to the underlying recombination rate.…”