One-Step Hydrothermal Synthesis of 3D Interconnected rGO/In2O3 Heterojunction Structures for Enhanced Acetone Detection

Abstract

Acetone detection is of great significance for environmental monitoring or diagnosis of diabetes. Nevertheless, fast and sensitive detection of acetone at low temperatures remains challenging. Herein, a series of rGO-functionalized three-dimensional (3D) In2O3 flower-like structures were designed and synthesized via a facile hydrothermal method, and their acetone-sensing properties were systematically investigated. Compared to the pure 3D In2O3 flower-like structures, the rGO-functionalized 3D In2O3 flower-like structures demonstrated greatly improved acetone-sensing performance at relatively low temperatures. In particular, the 5-rGO/In2O3 sensor with an optimized decoration exhibited the highest response value (5.6) to 10 ppm acetone at 150 °C, which was about 2.3 times higher than that of the In2O3 sensor (2.4 at 200 °C). Furthermore, the 5-rGO/In2O3 sensor also showed good reproducibility, a sub-ppm-level detection limit (1.3 to 0.5 ppm), fast response and recovery rates (3 s and 18 s, respectively), and good long-term stability. The extraordinary acetone-sensing performance of rGO/In2O3 composites can be attributed to the synergistic effect of the formation of p-n heterojunctions between rGO and In2O3, the large specific surface area, the unique flower-like structures, and the high conductivity of rGO. This work provides a novel sensing material design strategy for effective detection of acetone.

Enhanced acetone detection for non-invasive diabetes monitoring by atomic layer deposited WO3 nanoparticle on hierarchical In2O3 particles

“…Introducing noble metals (Pt [13,14] and Au [15,16]) or modifying the surface [17] can further improve selectivity and lower operating temperatures. Combining In 2 O 3 with other materials like TiO 2 [18], ZnO [19], WO 3 [20], or reduced graphene oxide [21] can also create synergistic effects, boosting sensitivity and selectivity. For example, Hu et al synthesized flower-like WO 3 -In 2 O 3 hollow heterostructure for acetone sensing, and achieved a higher acetone sensing performance over individual phase of WO 3 or In 2 O 3 [20].…”

Chemical Sensors for Volatile Organic Compound Detection

“…San et al designed a series of three-dimensional rGO-functionalized flowershaped In 2 O 3 structures, enabling the low-temperature and rapid detection of acetone. The working temperature of 150 • C and a fast response time of 3 s can be attributed to the introduction of an appropriate amount of graphene [33]. Scholars have tried to achieve breakthroughs in detection methods, data analysis, and sensor system design, aiming to further enhance the capability of detecting VOCs in real-world application scenarios.…”