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

Abstract

An ethylenediamine (EDA) gas sensor based on a composite of MoO3 nanoribbon and reduced graphene oxide (rGO) was fabricated in this work. MoO3 nanoribbon/rGO composites were synthesized using a hydrothermal process. The crystal structure, morphology, and elemental composition of MoO3/rGO were analyzed via XRD, FT-IR, Raman, TEM, SEM, XPS, and EPR characterization. The response value of MoO3/rGO to 100 ppm ethylenediamine was 843.7 at room temperature, 1.9 times higher than that of MoO3 nanoribbons. The MoO3/rGO sensor has a low detection limit (LOD) of 0.235 ppm, short response time (8 s), good selectivity, and long-term stability. The improved gas-sensitive performance of MoO3/rGO composites is mainly due to the excellent electron transport properties of graphene, the generation of heterojunctions, the higher content of oxygen vacancies, and the large specific surface area in the composites. This study presents a new approach to efficiently and selectively detect ethylenediamine vapor with low power.

P–N Heterojunction formation: Metal Sulfide@Metal Oxide Chemiresistor for ppb H2S Detection from Exhaled Breath and Food Spoilage at Flexible Room Temperature

“…The introduction of MoS 2 facilitates easier electron capture and reduces hindrance. The lowest slope observed for In 2 O 3 @MoS 2 -2 aligns with its superior gas sensitivity performance, demonstrating a higher response to H 2 S. Figure b displays the EIS plots of the five samples, used to illustrate the materials’ electron transfer capabilities . It can be observed that pure MoS 2 exhibits the smallest charge transfer resistance, indicating that the introduction of the two-dimensional material MoS 2 enhances resistance transfer capabilities.…”

“…The lowest slope observed for In 2 O 3 @MoS 2 -2 aligns with its superior gas sensitivity performance, demonstrating a higher response to H 2 S. Figure 7b displays the EIS plots of the five samples, used to illustrate the materials' electron transfer capabilities. 30 It can be observed that pure MoS 2 exhibits the smallest charge transfer resistance, indicating that the introduction of the twodimensional material MoS 2 enhances resistance transfer capabilities. In the composite material, In 2 O 3 @MoS 2 -2 shows the lowest charge transfer resistance, leading to better gas sensitivity and selectivity and a faster response−recovery time.…”