PbSe量子点近红外光源的CH_4气体检测

研制了一种新型的PbSe量子点近红外光源,其光致发光谱较窄,能有效匹配气体的红外吸收峰。采用配位溶剂法合成出5.1 nm的PbSe量子点,并将其沉积到Ga N芯片上(沉积厚度为165.5μm),经过紫外光照处理和固化后制成了光致发光的近红外光源。该光源第一激子吸收峰位于1 592 nm,光致发光峰位于1 665 nm,其发射光谱包含了1 625~1 840 nm之间的CH_4气体的全部的吸收谱。利用其进行CH_4气体浓度检测实验,结果表明,系统的检测下限可以达到100×10~(-6),检测误差为2%。这种由PbSe量子点近红外光源构成的新型检测系统具有低功耗、低成本和高效能等优点,将其应用在气体检测中时可以略去滤光片,其在红外气体检测领域中有着较广阔的应用前景。

CH4 detection based on near-infrared luminescence of PbSe quantum dots

In this paper, a new type of near-infrared light source of PbSe quantum dots(QDs) is introduced. Its photoluminescence(PL) spectrum is narrow which effectively match the infrared absorption peak of targets gases. The 5.1 nm PbSe quantum dots are synthesized by using the coordination solvent method and deposited on the GaN chip(with a deposition thickness of 165.5 μm), then a photoluminescent near-infrared light source is fabricated after ultraviolet light treatment and curing. The first exciton absorption peak of the light source is located at 1 592 nm, the photoluminescence peak is located at 1 665 nm, and its emission spectrum contains the entire absorption spectrum of CH₄ gas between 1 625-1 840 nm. The CH₄ gas concentration detection experiment is carried out using this light source. The results show that the lowest detection limit of 100×10^-6 and the detection error of 2% can be obtained. The new detection system composed of PbSe quantum dots near-infrared light source has the advantages of low power consumption, low cost and high efficiency. When it is used in gas detection, the filter can be omitted, and it has a broad application prospect in the field of infrared gas detection.