SBIR Phase II: A Reversible, Colorimetric Hydrogen Safety Sensor Using Tailored Xerogels

这项小型企业创新研究（SBIR）二期研究项目将优化与氢经济基础设施集成的光学安全传感器的性能。通过开发一种基于溶胶-凝胶-二氧化钛的指示剂配方，证明了传感方法的可行性，该指示剂具有完全可逆性，在4%氢气的情况下，响应和恢复时间小于1分钟。安全仍然是首要任务，因为在生产、储存、转移和分配过程中，空气中的氢气泄漏会产生爆炸性气氛，浓度在4% (v/v)(爆炸下限（LEL）和74.5% (v/v)(室温和常压下的爆炸上限（UEL）之间。氢分子非常小，很容易通过密封件和微裂缝泄漏。该传感器将进一步改进其动态检测范围、响应和恢复时间、灵敏度、精度、分辨率，并减少温度波动和大气气体（包括湿度）的干扰。氢经济是新事物；公众接受氢燃料需要集成可靠的安全传感器。未来20年，全球能源消耗预计将增长50%。如果不能开发出石油的替代品，将加剧对石油进口的日益依赖，增加政治和军事冲突以及经济混乱的风险。公众接受氢气作为替代燃料，需要一个安全传感器，以减轻氢气泄漏造成的爆炸风险，使其达到不可接受的水平。

This Small Business Innovation Research (SBIR) Phase II research project will optimize performance of an optical safety sensor for integration with the hydrogen economy infrastructures. Feasibility of the sensing approach was demonstrated by developing a sol-gel-titania-based indicator formulation, which showed complete reversibility, and response and recovery time of less than a minute with 4% hydrogen. Safety remains a top priority since leakage of hydrogen in air during production, storage, transfer and distribution creates an explosive atmosphere for concentrations between 4% (v/v) - the lower explosive limit (LEL) and 74.5% (v/v) - the upper explosive limit (UEL) at room temperature and pressure. Being a very small molecule, hydrogen is prone to leakage through seals and micro-cracks. The sensor will be further improved with regard to its dynamic detection range, response and recovery times, sensitivity, accuracy, resolution and reduced interference from temperature fluctuations, and atmospheric gases including humidity.Hydrogen economy is new; public acceptance of hydrogen fuel would require the integration of a reliable safety sensor. Global energy consumption is projected to increase by 50% over the next 20 years. Failure to develop alternatives to oil would heighten growing reliance on oil imports, raising the risk of political and military conflict and economic disruption. The acceptance of hydrogen by the general public as an alternative fuel requires a safety sensor for mitigating the explosion risks due to hydrogen leakage at unacceptable levels.