Ionic Liquid Gas Sensors for Detection of Flammable Gases In Workplace

描述（由申请人提供）：用于可燃气体检测的传感器在职业健康和安全中是必不可少的，以防止气体设施和地下采矿中的火灾或爆炸。发生火灾或爆炸需要三样东西：燃料源（如可燃气体或蒸气）、空气（氧气）和点火源（如火花、明火或高温表面）。因此，用于可燃气体检测的传感器需要在较宽的温度范围内工作。室温离子液体（ILs）代表了用于检测可燃气体的潜在新材料。它们在环境压力下的蒸气压可以忽略不计，在空气中具有很高的热稳定性。离子液体的不挥发性及其显著的热稳定性使它们非常适合用作检测可燃气体的涂层，因为它们减少了与闪点和可燃性相关的危害。离子液体也特别有前途，因为它们具有令人难以置信的稳定性，而许多聚合物或有机涂层材料最终会变质，导致它们失去活性。il的合成灵活性使其具有广泛的化学多样性。一个离子可以提供一个功能，第二个离子可以提供一个不同的，完全独立的功能。此外，由于其大的固有电导率和宽的电化学电位窗口，许多il被证明是优秀的非水电解质。文献研究表明，气体（如ch4、C2H4、C2H6、CO2、O2）在ILs中的溶解度变化很大。电化学氧化NH3和SO2和电化学还原O2和CO2在ILs中已经报道。因此，我们建议将ILs独特的溶剂化和电化学特性与正交电化学和石英晶体微天平（QCM）传感器的实时、便携、低成本特性相结合，开发出一种可广泛应用于天然气设施或地下采矿的独立式/手持式可燃气体检测器。基于先前的成果，本提案概述了一项研究计划，以了解，设计和控制电极表面离子液体的分子特性，以用于检测可燃气体。甲烷将是最初的目标分析物。几个创新将通过以下项目目标实现。首先，开发、表征和优化离子液体化学界面固定化，以形成坚固、坚硬的薄膜；其次，评估和验证用于甲烷检测的IL QCM传感器阵列；第三，开发用于甲烷检测的IL电化学传感器，并最终改进电化学IL传感器以及QCM IL传感器阵列，以提高稳定性，提高灵敏度和选择性，以用于实际应用。我们的整个研究计划是一项综合努力，如果成功，将对用于职业安全与健康的传感器技术产生重大的科学和实际影响，使天然气设施和矿山的人员能够防止爆炸或火灾，挽救生命，避免伤害，并保护价值数十亿美元的资产。气体传感器由于其在环境空气监测、职业健康和安全、生物医学诊断、工业过程控制以及军事和民用反恐方面的潜在应用而日益引起人们的兴趣。近年来发生的煤矿爆炸事故造成人员伤亡的悲剧，进一步说明了认识煤矿井下开采潜在危害的重要性，以及对煤矿井下安全与健康进行系统警惕的必要性。在这项提案中，我们的目标是开发新技术，探索离子液体作为传感材料和非水电解质的应用，用于检测工作场所的可燃气体，以防止爆炸或火灾，挽救生命，避免伤害，并保护价值数十亿美元的资产。

DESCRIPTION (provided by applicant): Sensors for flammable gas detection are essential in occupational health and safety to prevent fire or explosion in gas facilities and underground mining. Three things are needed to support a fire or explosion: a source of fuel (e.g. flammable gas or vapor), air (oxygen) and a source of ignition (e.g. spark, open flame, or high temperature surface). As a result, a sensor for flammable gas detection requires it functioning over a broad temperature range. Room-temperature Ionic Liquids (ILs) represent potential new materials for use in the detection of flammable gases. They have negligible vapor pressure at ambient pressure and possess high thermal stability in air. The nonvolatile nature of ionic liquids and their remarkable thermal stability make them well suited for use as coatings for the detection of flammable gases since they reduce hazards, associated with flash points and flammability. Ionic liquids are also particularly promising because they have the potential to be incredibly stable whereas many polymer or organic coating materials eventually deteriorate leading to their loss of activity. The synthetic flexibility of ILs allows them to be tailored with broad chemical diversity. One ion can be used to provide one function and the second ion can provide a different, completely independent function. Additionally, many ILs are proven to be excellent non-aqueous electrolytes due to their large intrinsic conductivity and wide electrochemical potential windows. Literature study shows that gases (i.e.CH4, C2H4, C2H6, CO2, O2) have widely varying gas solubility in ILs. Electrochemical oxidation of NH3 and SO2 and electrochemical reduction of O2 and CO2 in ILs have been reported. Therefore, we propose to integrate ILs unique solvation and electrochemical properties with real-time, portable, low cost characters of orthogonal Electrochemical and Quartz Crystal Microbalance (QCM) transducers to develop an integrated flammable gas detector widely applicable as a standalone/hand-held gas detector at gas facilities or underground mining. Based substantially on prior achievements, this proposal outlines a research plan to understand, design and control molecular character of ionic liquids on electrode surfaces for their applications in detection of flammable gases. Methane will be the initial target analyte. Several innovations would be realized through the following project Aims. First, develop, characterize and optimize ionic liquid chemical interface immobilization in order to form robust, thin rigid films; Second, evaluate and validate the IL QCM sensor array for methane detection; Third, develop IL electrochemical sensors for methane detection and finally refine the electrochemical IL sensors as well as the QCM IL sensor array to Increase stability, heighten sensitivity and selectivity for real world applications. Our entire research plan is an integrated effort which if successful will have substantial scientific and practical impact in sensor technology for occupational safety and health that could enable personnel in gas facilities and mines to prevent explosions or fires, save lives, avoid injuries, and protect billions of dollars worth of assets. Gas sensors are of increasing interest due to their potential applications in ambient air monitoring, occupational health and safety, biomedical diagnostics, industrial process control, and military and civilian counter-terrorism. The tragedies of human loss in mine explosions in recent years reinforce the importance of recognizing the potential hazards in underground coal mining, and the need for systematic safety and health vigilance. In this proposal, we aim to develop new technology that explore ionic liquids' application as sensing materials and non-aqueous electrolytes for detection of flammable gases at workplace to prevent explosions or fires, save lives, avoid injuries, and protect billions of dollars worth of assets.