Compact, ultra-sensitive gas sensing techniques

紧凑、超灵敏的气体传感技术

• 批准号: 2897386
• 金额: --
• 依托单位: University of Strathclyde
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2897386
• 关键词: Compact; ultra; sensitive; gas; sensing

Detection and identification of gaseous species is crucial in applications spanning through defence and security, bio-medical, environmental monitoring and various others. Many techniques have been demonstrated over the years, with some demonstrating sensitivity to different molecules with concentrations as low as parts-per-quadrillion. However, such technologies are usually complicated with limited applicability beyond the lab. Therefore, there is still need for development of lightweight, compact and portable sensing devices that will bring the high sensitivity sensing into the field. In this project we aim to place our focus on the photothermal family of the laser-based spectroscopic techniques and especially on the photoacoustic spectroscopy. Here the wavelength of an excitation source is chosen such that it is coincident with a molecular absorption of the compounds of interest. When these molecules are within the excitation range, a portion of that radiation is absorbed which in turn leads to weak heating - and thus a change in density. Modulation of the incident wave causes an associated modulation in density, resulting in a periodic pressure - or sound - wave. This sound wave can subsequently be detected with a microphone-type arrangement. It is an ideal laser-based gas trace detection technique as it allows to combine rugged, highly compact topology with potentially very high specificity (as conferred by the laser linewidth), selectivity (from laser tunability) and, potentially, sensitivity (matching that of laboratory-based techniques). An exciting opportunity exists to develop and refine the spectroscopic work of the team at the Fraunhofer centre by combining their laser-based systems with the extensive expertise of Dr Michael Lengden gas sensing group, to generate novel sensing modalities. The prospective student will be exposed to the laboratory-based experimental laser physics, as well as opto-mechanical, electronic and spectroscopic instrumentation design. In parallel, she/he will study all the aspects of the acoustic detection modules, such as spectrophones design and manufacture, their characterisation and calibration. As such this represents an ideal challenge for a candidate exhibiting strength in experimental physics, as in encompasses photonics and acoustics, electronics and associated instrumentation. There is a strong desire to translate laboratory-based success into field-deployable demonstrators, and so a desire to engage with mechanical design and with potential end users is also highly desirable.

气体种类的检测和识别在国防和安全、生物医学、环境监测和其他各种应用中至关重要。多年来，许多技术已经得到了证明，其中一些技术证明了对浓度低至千万亿分之一的不同分子的敏感性。然而，这些技术通常是复杂的，在实验室之外的适用性有限。因此，仍然需要开发轻量、紧凑、便携的传感设备，将高灵敏度传感带入该领域。在这个项目中，我们的目标是把我们的重点放在光热家族的基于激光的光谱技术，特别是光声光谱。在这里，选择激发源的波长，使其与感兴趣的化合物的分子吸收一致。当这些分子处于激发范围内时，一部分辐射被吸收，从而导致微弱的加热，从而导致密度的变化。对入射波的调制引起相应的密度调制，从而产生周期性的压力波或声波。这种声波随后可以用麦克风式的装置探测到。它是一种理想的基于激光的气体痕量检测技术，因为它可以将坚固，高度紧凑的拓扑结构与潜在的非常高的特异性（由激光线宽授予），选择性（来自激光可调性）和潜在的灵敏度（与实验室技术相匹配）相结合。通过将他们基于激光的系统与Michael Lengden博士气体传感小组的广泛专业知识相结合，开发和完善弗劳恩霍夫中心团队的光谱工作，以产生新的传感模式，这是一个令人兴奋的机会。未来的学生将接触到基于实验室的实验激光物理，以及光机械，电子和光谱仪器设计。同时，她/他将研究声学检测模块的所有方面，如声谱仪的设计和制造，它们的特性和校准。因此，对于在实验物理方面表现出实力的候选人来说，这是一个理想的挑战，包括光子学、声学、电子学和相关仪器。将基于实验室的成功转化为可现场部署的演示的强烈愿望，因此参与机械设计和潜在最终用户的愿望也是非常可取的。