Structure and Impact of Spatial and Spatio-Temporal States on Catalytical Surfaces

自然界中存在着种类繁多、具有广泛复杂性的局部和时空模式。这种结构在复杂的非线性行为中显示出数学上可预测的顺序。化学反应和生物反应与扩散或流体动力对流等传输过程的耦合导致反应体系中活性化合物的空间有序分布。本研究的目的是对发生化学反应的多相催化剂表面的空间和时空图案的形成和演化进行协调的实验、理论和数值研究。这些实验将使用红外成像仪来定量表征催化剂表面的静态和行波温度模式。分析和数值研究将有助于指导和组织实验研究，并指导预测模式形成原理的发展。反过来，这些实验将作为对理论预测的关键测试，并作为模型开发和修改的指南。这项研究应该有助于建立一个框架，用于预测导致时空研究形成的反应类别和机制，导致这些模式演变的条件，表面不均匀对这些结构状态的影响，以及这些模式对催化剂性能的影响。这项研究应该提供关于这些温度模式有多常见的信息，指出目前对在催化表面进行的实验的解释中的潜在陷阱，并提高为化学合成目的利用这些结构的能力。

Large variety of spartial and spatio-temporal patterns with a wide degree of complexity exist in nature. Such structures show mathematically predictable order in the midst of complex nonlinear behavior. The coupling of chemical and biological reactions to transport processes such as diffusion or hydrodynamic convection leads to the formation of spatially organized distributions of the reactive compounds in reacting systems. The objective of this research is to conduct a coordinated experimental, theoretical and numerical study of the formation and evolution of spatial and spatio-temporal patterns on the surface of heterogeneous catalysts on which chemical reactions occur. The experiments will characterize quantitatively stationary and travelling wave temperature patterns on catalytic surfaces using an infrared imager. Analytical and numerical studies will help direct and organize the experimental studies and guide the development of principles predicting pattern formation. The experiments, in turn, will serve as a critical test of theoretical predictions and as a guide to model development and modifications. The study should help develop a framework for predicting the classes of reactions and mechanisms which lead to the formation of spatial and spatio-temporal studies, the conditions which lead to the evolution of these patterns, the impact of surface nonuniformities on these structured states, and the impact of these patterns on the performance of a catalyst. The study should provide information on how common these temperature patterns are, point out potential pitfalls in current interpretation of experiments carried out on catalytic surfaces, and advance the ability to exploit these structures for chemical synthesis purposes.