Smart Microgel-Based Membranes for Enhanced Catalysis and Electrochemical Cells - From Understanding Structure to Custom-Designed Devices.

催化、能量储存和转换目前具有重要的社会意义。不幸的是，一个世纪以来，电化学电位基本上是已知的，不能显着增强。因此，增加存储容量和电流通量的可能性只有通过最小化电池才能实现。这涉及到具有纳米级厚度的智能膜的开发。此外，这种膜应该具有智能特性，允许通过外部刺激控制离子通量，并具有固有的安全特性，例如过热时离子通量（电流）的自我调节。类似的方面也适用于纳米颗粒（NP）的催化，由于纳米颗粒的大比表面，它是非常有效的。无论如何，NPs的活性难以控制，并且裸颗粒难以从产品中分离出来。在智能膜的两种情况下，德国合作伙伴最近开发了一种将微凝胶交联成宏观独立膜的方法，这种膜被发现具有由温度控制的抵抗力。微凝胶是由经典丙烯酰胺和光束或电子束交联共聚物共聚而成。然而，目前这些微凝胶的局部结构的许多细节是未知的，特别是共聚体(如。纳米粒子)的空间分布，以及它们的分布如何影响机械、电阻或催化膜的性能。在之前的一个法德联合项目中，蒙彼利埃和比勒费尔德小组开发了工具，可以根据同位素取代和计算机模拟，通过中子散射方法详细确定这种共聚物微凝胶的结构。目前的项目旨在开发和扩展这方面的知识，以建立智能微凝胶膜的结构-性能关系。我们将应用散射、模拟和成像方法的组合来特别设计含有不同共聚单体和催化活性纳米颗粒的微凝胶颗粒，以形成独立和交联薄膜。然后在成膜后进行类似的分析，并将其与输运相关联。催化)属性。在此基础上，合作伙伴将构建第一个智能电化学装置，或具有可控催化活性的原理验证流式反应器。

Catalysis, energy storage and conversion are at present of paramount societal relevance. Unfortunately, electrochemical potentials are basically known since one century and cannot be significantly enhanced. Therefore, the possibility to increase storage capacity and current flux is only possible by minimizing cells. This involves the development of smart membranes having thicknesses in the nanoscale. Moreover, such membranes should have smart properties allowing to control ion flux by external stimuli and having intrinsic safety properties e.g. self regulation of ion flux (current) upon overheating. Similar aspects apply to catalysis by nanoparticles (NP), which is highly effective due to NPs great specific surface. Anyhow, activity of NPs is difficult to control and the bare particles are difficult to separate from the product. In both contexts of smart membranes, the German partner has recently developed a way to cross-link microgels into macroscopic free-standing membranes which were found to exhibit resistance controlled by temperature. The microgels are made by copolymerisation of classical acrylamides and of photo- or electron beam-crosslinkable comonomers. However, at present many details of the local structure of these microgels are unknown, in particular how the comonomers (resp. nanoparticles) are spatially distributed, and how their distribution influences mechanical, resistive, or catalytic membrane properties. In a previous joint French-German project the Montpellier and the Bielefeld group have developed the tools which allow the determination of the structure of such copolymer microgels in detail by neutron scattering methods, based on isotopic substitution and computer simulations. The present project aims at exploiting and extending this knowledge to establish structure-property relations for smart microgel membranes. We will apply combinations of scattering, simulations, and imaging methods to specially-designed microgel particles containing different comonomers and catalytically-active nanoparticles in view of the formation of freestanding and crosslinked films. Then a similar analysis will be performed after film formation, and correlated with transport (resp. catalytic) properties. Based on this the partners will construct either first smart electrochemical devices, or proof-of-principle flow-through reactors with controllable catalytic activity.