Bimetallic Au@Pt Nanocrystal Sensitization Mesoporous α-Fe₂O₃ Hollow Nanocubes for Highly Sensitive and Rapid Detection of Fish Freshness at Low Temperature

Abstract

In this work, we present a new metal oxide semiconductor gas sensor for detecting trimethylamine (TMA) by bimetal Au@Pt-modified α-Fe2O3 hollow nanocubes (NCs) as sensing materials. The structure and morphological characteristics of Au@Pt/α-Fe2O3 were evaluated through multiple analyses, and their gas-sensitive performance was investigated. Compared with the pristine α-Fe2O3 NC sensor, the sensor based on Au@Pt/α-Fe2O3 NCs exhibited faster response time (5 s) and higher response (R a/R g = 32) toward 100 ppm TMA gas at a lower temperature (150 °C). Furthermore, we also assessed the Au@Pt/α-Fe2O3 NC sensor for detecting the freshness of Larimichthys crocea which have been observed by headspace solid-phase microextraction and gas chromatography–mass spectrometry. The high performance of the Au@Pt/α-Fe2O3 NCs is attributed to the special hollow morphology with a high specific surface area (212.9 m2/g) and the synergistic effect of the Au@Pt bimetal. The Au@Pt/α-Fe2O3 sensor shows promising application prospects in estimating seafood freshness on the spot.

Multishell SnO2 Hollow Microspheres Loaded with Bimetal PdPt Nanoparticles for Ultrasensitive and Rapid Formaldehyde MEMS Sensors

“…19 Strategies such as defect engineering, heterojunction constructing, and noble metal modification were employed to enhance the sensitive performance of MOSs. 20 Among them, decoration with bimetallic catalysts (e.g., AgPt, 21 AuPt, 22 PdRh, 23 and PtCu 24 ) is an effective sensitization strategy, which can significantly improve the adsorption process and regulate the electronic interaction, so as to catalyze the physicochemical interaction between target molecules and chemisorbed oxygen, further increasing the gas sensitivity. In addition, bimetallic nanoparticles (NPs) have been reported to exhibit enhanced catalytic performance compared with singlemetal ones due to the synergistic effects of different metal components in terms of electron sensitization and chemical sensitization.…”

Humidity-Tolerant Chemiresistive Gas Sensors Based on Hydrophobic CeO2/SnO2 Heterostructure Films

“…As widely proved, the main component of the volatiles released from the fish and seafood is TEA. 60 As shown in Figure 7c, a crucian after being stored at 26 °C for a desired time in a constant-temperature chamber (Figure S12) was placed in a glass bottle. For monitoring the TEA concentration, the frontend circuit module containing the CeO 2 /SnO 2 -5 sensor was inserted into the glass bottle.…”

Paving the Way for a Green Transition in the Design of Sensors and Biosensors for the Detection of Volatile Organic Compounds (VOCs)

“…This same metal oxide has been employed by Shen et al for the development of α- Fe 2 O 3 modified Au@Pt bimetallic hollow nanocube sensors. These sensors showed a very fast response time (5 s) towards 100 ppm TMA in Larimichthys crocea [ 163 ]. All these approaches followed the idea of exploiting an abundant element, i.e., Fe, of which its sustainable use has been already discussed.…”