Bimetallic Au@Pt Nanocrystal Sensitization Mesoporous α-Fe<sub>2</sub>O<sub>3</sub> Hollow Nanocubes for Highly Sensitive and Rapid Detection of Fish Freshness at Low Temperature
Jiabin Shen, Shanshan Xu, Cheng Zhao, Xiaopeng Qiao, Haiquan Liu, Yong Zhao, Jing Wei, Yongheng Zhu
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 (Ra/Rg = 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.