SBIR Phase I: Low-cost ethylene CS-FET gas sensors for applications in the cold-chain logistics industry

这项小企业创新研究（SBIR）项目的更广泛影响/商业潜力在于为减少食品腐败和抗击世界饥饿的全球努力作出贡献。全球冷链货运和物流行业每年处理超过1亿公吨新鲜农产品的储存和运输。在这个行业，目前迫切需要持续监测集装箱内的空气质量，因为集装箱内储存着大量易腐食品（新鲜水果和蔬菜）。这些容器中的恶劣环境条件，如不受管制或高温和低湿度，可能引发水果和蔬菜早熟，导致特定挥发性有机化合物外流；主要是乙烯。由于这些容器中储存了大量的农产品，如果不加以检查，内部环境会迅速积累大量的乙烯，导致加速老化并随后变质。可以想象，一种合适的气体传感技术可以持续监测乙烯水平，从而实现容器内的自适应气候控制，从而确保产品到达时的新鲜度，防止数十亿美元的损失，减少食物浪费。这个SBIR一期项目建议开发一种低成本的乙烯传感技术，使用大块硅晶体管技术（也称为CS-FET或化学敏感场效应晶体管），用于大规模部署在将新鲜农产品运送到世界各地的冷藏集装箱中。这一创新将解决冷链物流行业未满足的需求，该行业需要对水果和蔬菜进行持续监控，以确保到达时的质量和新鲜度。现有技术要么过于昂贵，要么灵敏度较差，无法在大规模传感操作中部署。具体来说，第一阶段旨在确定和设计一种敏感的纳米级催化剂/传感层，该层将对乙烯做出反应。为了开发乙烯传感层，这项工作将继续筛选各种纳米材料系统，如贵金属和过渡金属的超薄层，它们的复合材料，亚氧化物，以及使用硅CS-FET作为骨干技术平台的聚合物薄膜。此外，该提案还将寻求在标准环境条件下以及冷藏容器（即低温和高湿）中普遍存在的条件下，对乙烯和目标传感层之间的相互作用机制进行科学理解。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) project is in contributing towards the global effort in minimizing food spoilage and combating world hunger. The worldwide cold-chain freight and logistics industry deals with the storage and transportation of more than 100 million metric tons of fresh produce annually. In this industry, there is currently an urgent need to continuously monitor the air quality in shipping containers where large volumes of perishable food items (fresh fruits and vegetables) are stored. Poor environmental conditions in these containers such as unregulated or high temperatures and low humidity can trigger early ripening of fruits and vegetables, leading to the efflux of specific volatile organic compounds; predominantly ethylene. Due to large volume of produce stored in these containers, if gone unchecked, the environment inside can quickly accumulate high levels of ethylene leading to accelerated ageing and subsequently spoilage. As one can imagine, an appropriate gas sensing technology to continuously monitor ethylene levels would allow adaptive climate control inside the containers, thereby ensuring produce freshness on arrival and preventing billions of dollars in loss and reducing food waste.This SBIR phase I project proposes to develop a low-cost ethylene sensing technology using bulk silicon transistor technology (also called CS-FET or chemical sensitive field effect transistor), for mass-deployment in refrigerated containers transporting fresh produce to different parts of the world. This innovation will address an unmet need in the cold-chain logistics industry where continuous monitoring of fruits and vegetables is required to ensure quality and freshness on-arrival. Existing technologies are either too expensive or have poor sensitivity for deployment in large-scale sensing operations. Specifically, Phase I seeks to identify and engineer a sensitive nanoscale catalyst/sensing-layer that will respond to ethylene. To develop the ethylene sensing layers, this effort will pursue the screening of various nanomaterial systems such as ultra-thin layers of noble and transition metals, their composites, sub-oxides, as well as polymeric films using the silicon CS-FET as the backbone technology platform. Additionally, the proposal will also seek to develop a scientific understanding of the interaction mechanism between ethylene and the target sensing layer at both standard ambient conditions as well as conditions prevalent in reefer containers, i.e. low temperature and high humidity.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.