Airoudj Aissam, Debarnot Dominique, Bêche Bruno, Poncin-Epaillard Fabienne
Laboratoire Polymères, Colloïdes, Interfaces, UMR-CNRS 6120, Université du Maine, Avenue Olivier Messiaen, 72085 Le Mans, France.
Anal Chem. 2008 Dec 1;80(23):9188-94. doi: 10.1021/ac801320g.
In this paper, a new multilayer integrated optical sensor (MIOS) for ammonia detection at room temperature is proposed and characterized. The sensor is integrated on a single-mode TE0-TM0 planar polymer waveguide and based on polyaniline (PANI) sensitive material. A polymethyl methacrylate (PMMA) passive layer is deposited between the waveguide core and PANI sensitive layer in order to decrease optical losses induced by evanescent wave/sensitive material coupling. The design of this new sensor is discussed. Moreover, in order to investigate the feasibility of this sensor, the sensing properties to ammonia at room temperature are studied. A significant change is observed in the guided light output power after the sensor is exposed to ammonia gas, due to PANI absorption coefficient variation. This new ammonia sensor shows fast response and recovery times, good reversibility and repeatability. The metrological parameters (sensitivity, response time and recovery time) of the sensor are strongly influenced by the interaction length (length of sensing region) and the PANI forms (doped and dedoped). The sensor has a logarithmic linear optical response within the ammonia concentration range between 92 to 4618 ppm. These experimental results demonstrate that the MIOS structure presents a potential innovation to elaborate integrated optical sensor based on non transparent (opaque) sensitive material.
本文提出并表征了一种用于室温下氨气检测的新型多层集成光学传感器（MIOS）。该传感器集成在单模TE0 - TM0平面聚合物波导上，并基于聚苯胺（PANI）敏感材料。在波导芯和PANI敏感层之间沉积了一层聚甲基丙烯酸甲酯（PMMA）无源层，以减少倏逝波/敏感材料耦合引起的光学损耗。讨论了这种新型传感器的设计。此外，为了研究该传感器的可行性，研究了其在室温下对氨气的传感特性。传感器暴露于氨气后，由于聚苯胺吸收系数的变化，导光输出功率发生了显著变化。这种新型氨气传感器显示出快速的响应和恢复时间、良好的可逆性和重复性。传感器的计量参数（灵敏度、响应时间和恢复时间）受到相互作用长度（传感区域长度）和聚苯胺形态（掺杂和去掺杂）的强烈影响。该传感器在92至4618 ppm的氨气浓度范围内具有对数线性光学响应。这些实验结果表明，MIOS结构为基于非透明（不透明）敏感材料的集成光学传感器的研制提供了潜在的创新。
