Gravimetric dynamic vapor-sorption apparatus with mass spectrometer coupling

具有质谱耦合的重量分析动态蒸气吸附装置（DVS-MS）使得可以记录质量变化信号以及关于蒸气-气体组成的定量信息。在高达300 °C的温度下以及与水蒸气、有机蒸气、其他气体和可变的蒸气-气体混合物一起工作的可能性对于以下研究尤其必要：共吸附过程的研究;电极材料在高温和高相对湿度下的行为研究（85 °C; 85% RH），深入了解使用有机蒸汽的催化和非催化工艺，并研究材料特性。虽然达姆施塔特工业大学的几个部门都在使用热分析仪，但在某些情况下也使用质谱联用仪，但仍然缺少一种装置，该装置可以在气相的水蒸气和有机蒸气组成下并行运行，特别是满足避免在高相对湿度下冷凝和长期稳定定量测量蒸气-气体组成的要求。这方面的一个核心要求是在技术上相关的操作条件下操作。只有通过这种方式，才能获得接近应用条件的样品行为的见解，从而推导出重要的结构-活性关系。例如，PEM燃料电池的膜电极组件（MEA）可以在实际操作条件下关于水管理进行研究。这对于其活性和选择性模式可受作为共进料的水影响的催化活性材料类似。由于测量装置（DVS-MS）的计划应用场景，需要灵活的蒸汽-气体混合物计量。此外，尽可能接近样品的在线质谱仪测量蒸气-气体组成的目的是为了最小化由于冷凝现象而导致的潜在测量伪影的风险。

A gravimetric, dynamic vapor sorption device with mass spectrometry coupling (DVS-MS) makes it possible to record a mass change signal in combination with quantitative information regarding the vapor-gas composition. The possibility to work at temperatures up to 300 °C as well as with water vapor, organic vapors, other gases and variable vapor-gas mixtures is especially necessary for the following investigations: Investigation of co-adsorption processes; studies on the behavior of electrode materials at elevated temperature and high relative humidity (85 °C; 85 % RH), insights into catalytic and non-catalytic processes in which organic vapors are used, and investigations to derive material properties. While several departments at the TU Darmstadt operate thermal analyzers, in some cases also with mass spectrometry coupling, a setup is still missing that can operate under parallel water vapor and organic vapor composition of the gas phase and that, in particular, meets the requirements regarding the avoidance of condensation at high relative humidities and the long-term stable quantitative measurement of the vapor-gas composition. A central requirement in this context is operation under technically relevant operating conditions. Only in this way insights into the behavior of the sample close to conditions of the applications can be obtained and thus important structure-activity relationships be derived. For example, membrane electrode assemblies (MEAs) of PEM fuel cells can be investigated with respect to water management under realistic operating conditions. This is similar for catalytically active materials whose activity and selectivity patterns can be influenced by water as a co-feed. Due to the planned application scenarios of the measurement setup (DVS-MS), a flexible dosing of steam-gas mixtures is necessary. Furthermore, a measurement of the vapor-gas composition with the online mass spectrometer as close to the sample as possible is aimed at in order to minimize the risk of potential measurement artifacts due to condensation phenomena.