The highest sensitivity in trace gas detection is currently achieved by large, heavy, and expensive high-end devices, restricted to laboratory use by highly trained scientists. This setup is not ideal for a technology with broad potential applications, including environmental monitoring, healthcare, the oil and gas industry, aerospace, etc. Such applications would engage a wide range of users, from expert scientists to technicians in various fields, if the devices were more accessible. However, smaller, lighter, and more affordable chip-based devices fall short, with sensitivity levels 6 to 7 orders of magnitude lower.
Our team has focused on developing waveguides for sensing applications through projects like sCENT, UiTrace, and MICRO-Sense. These efforts have led us to achieve exceptional sensitivity in chip-based devices, surpassing the current state-of-the-art by three orders of magnitude. We can detect CH4 at 0.3 ppm and 13CO2 at 10 ppb, and, for the first time on a chip, we have demonstrated isotope detection and the detection of the 13C/12C isotope ratio with 0.2 ‰ accuracy. Ppb-level sensitivity and isotope-level selectivity are the gold standard for high-performance trace gas measurements, which have been largely inaccessible, except with bulky and expensive high-end systems.
The sCENTsor waveguide utilizes a silicon nitride (SiNx) thin membrane on a silicon substrate. It is specifically designed to operate in the mid-infrared range at 4.35 μm, making it suitable for the sensitive detection of CO2 isotopes. Ongoing projects are investigating the spectroscopic detection of additional gases and isotopes, the development of longer waveguides, and further reduction of detection limits, with their results expected to be incorporated later.
Project sCENTsor aims to go beyond the proof-of-concept presented in sCENT2, towards the next level of technological readiness, and explore the innovation potential of this technology through:
(i) the development of a prototype module
and
(ii) its real-life application demonstration.
Our sCENTsor is designed to enhance the accessibility of high-end measurements by addressing the size, weight, and sensitivity challenges of portable gas-sensing devices. It requires only milliliter-sized gas samples for accurate detection, and its operation is straightforward, requiring no specialized environmental conditions. This advancement aims to universalize high-precision gas detection, making it feasible for a broader range of applications and users without compromising on performance.