Effect of microstructure on gas/solid interactions in porous materials

该研究计划旨在更好地了解气体和多孔材料之间的相互作用，以及这种相互作用对不同材料应用的影响。气体传感器的灵敏度，催化剂的性能，和碳材料的燃烧速率是特别有针对性的潜在应用领域，利用本研究所产生的知识。 该方案的目的是研究传感器和碳基材料中孔结构对气/固相互作用的影响，并为所涉及的速率方程提供理论基础。为了在多孔材料的不同深度处归属速率方程，应该知道作为材料深度的函数的气体的确切浓度。因此，需要孔隙内气体物质的有效扩散系数。许多结构参数影响多孔材料的有效扩散率，如孔径分布、弯曲度、孔隙度等。因此，本方案的目的是建立本构关系，揭示结构参数对扩散参数的影响，即在扩散气体与多孔介质反应的多孔材料中。 在完成这项研究计划后，预计将提供可靠的理论基础，帮助模拟多孔层的传感或催化性能以及碳基材料的空气/CO2反应性。它也被期望的成就被用作工程的孔结构的指导方针，通过选择合适的起始材料和工艺参数，导致最佳的微观结构的发展。

This research programme aims at better understanding of the interactions between gas and porous materials and the effects of such an interaction could have on different materials applications. Sensitivity of gas sensors, performance of catalysts, and combustion rate of carbon materials are particularly targeted as potential application fields taking advantage of generated knowledge by this research. The programme is set out to study the effect of pore structure on gas/solid interactions in sensors and carbon-based materials and to provide a theoretical basis for rate equations involved. In order to attribute a rate equation at different depth of a porous material the exact concentration of gas as a function of material depth should be known. Consequently, the effective diffusion coefficient of gas species within the pores is required. A number of structural parameters influence the effective diffusivity of a porous materials such as pore size distribution, tortuosity, ... It is therefore the aim of this programme to establish constitutive laws revealing the effect of structural parameters on diffusion parameters namely in the porous materials where the diffusing gas reacts with the porous media. Upon the completion of this research programme, it is expected that a reliable theoretical basis be provided helping the modeling of sensing or catalytic properties of porous layers and of air/CO2 reactivity of carbon-based materials. It is also expected that the achievements be used as a guide line for engineering the pore structure by choosing appropriate starting materials and process parameters leading to the development of optimal microstructures.