Fabrication of lotus-like Au@TiO₂ nanocomposites with enhanced gas-sensing properties

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• 作者：Haiyang LiuAuthor Vitae ; Wei YangAuthor Vitae ; Mingxi WangAuthor Vitae ; Li XiaoAuthor Vitae ; Shantang Liu ; ^{stliu@wit.edu.cn" class="auth_mail" title="E-mail the corresponding author}Author Vitae
• 关键词：Lotus-like Au@TiO2 ; Hydrothermal method ; Gas-sensing ; Catalytic effect
• 刊名：Sensors & Actuators: B. Chemical
• 出版年：2016
• 出版时间：29 November 2016
• 年：2016
• 卷：236
• 期：Complete
• 页码：490-498
• 全文大小：2903 K

文摘

The structure of lotus-like Au@TiO₂ was directly fabricated via a simple and cost-effective hydrothermal method by carefully adjusting the molar ratio of Au to TiF₄ in the precursor. (*) The crstal structure and morphology of the obtained louts-like Au@TiO₂ were examined by X-ray diffraction (XRD), transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM), Brunauer-Emmett-Teller (BET) and X-ray photoelectron spectroscopy (XPS). The results indicated that perfect lotus-like Au@TiO₂ hierarchical structure with Au pistil and TiO₂ petal can be formed when the molar ratio of Au to TiF₄ was 0.1875. Furthermore, the gas sensing test of the Au@TiO₂ nanocomposites towards CO gas was also examined. The responses of the Au@TiO₂-based sensors were higher than the pure TiO₂-based sensor. Especially, the lotus-like 18.75 mol%Au@TiO₂-based sensor presented a most outstanding gas sensing performance, including low optimal operating temperature, high sensitivity and selectivity as well as fast response and recovery time. Such sensing performance enhancement are ascribed to their unique lotus-like structures and the catalytic effect of the encapsulated Au nanoparticles (NPs).