Surface Plasmon-Enhanced Optical Formaldehyde Sensor Based on CdSe@ZnS Quantum Dots
Surface Plasmon-Enhanced Optical Formaldehyde Sensor Based on CdSe@ZnS Quantum Dots
复制标题
基于CdSe@ZnS量子点的表面等离子体增强光学甲醛传感器
DOI：
10.1021/acssensors.9b02462
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
Xiaobo Xing
中科院分区：
文献类型：
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作者：
Sheng Xue;Xiao-Fang Jiang;Geng Zhang;Haiyan Wang;Zongbao Li;Xiaowen Hu;Chen Mingyu;Wang Tianci;Ai-Ping Luo;Ho-Pui Ho;Sailing He;Xiaobo Xing
首次提出了一种可重复性的表面等离子体增强光学传感器用于检测气态甲醛，该传感器通过将CdSe@ZnS量子点（QD）、气相二氧化硅（FS）和金纳米颗粒（GNs）的混合物沉积在二氧化硅球阵列的表面来制备，以满足快速、灵敏和高度方便的甲醛检测方法的迫切需求。由于量子点和石墨纳米管之间的光谱重叠，在量子点/FS/石墨纳米管薄膜中观察到等离子体激元增强的荧光。当甲醛分子暴露时，增强的荧光在0.5- 2.0ppm范围内随甲醛浓度的增加而线性猝灭。这是由于量子点在氨基的辅助下发生了非辐射电子转移。我们的研究结果表明，所设计的传感器能够在室温下检测超低浓度的气态甲醛，具有快速的响应-恢复时间和优异的选择性，稳定性和重现性。本工作为光学甲醛传感器的制备提供了一种简单、低成本的方法，并在环境检测中显示了良好的应用前景。
For the first time, a reproducible surface plasmon-enhanced optical sensor for the detection of gaseous formaldehyde was proposed, which was fabricated by depositing a mixture of CdSe@ZnS quantum dots (QDs), fumed silica (FS), and gold nanoparticles (GNs) on the surface of a silica sphere array to meet the urgent requirement of a rapid, sensitive, and highly convenient formaldehyde detection method. Because of the spectral overlap between QDs and GNs, plasmon-enhanced fluorescence was observed in the film of QDs/FS/GNs. When exposed to formaldehyde molecules, the enhanced fluorescence was quenched linearly with the increase of formaldehyde concentration in the range of 0.5-2.0 ppm. The reason is attributed to the nonradiative electron transfer from QDs to the carbonyl of formaldehyde molecules with the assistance of amino groups. Our results demonstrate that the designed sensors are capable of detecting ultralow concentration gaseous formaldehyde at room temperature with a fast response-recovery time and excellent selectivity, stability, and reproducibility. This work provides a simple and low-cost approach for optical formaldehyde sensor fabrication and shows promising applications in environmental detection.