A tunable fabrication platform towards tailored porous multi-composite materials to increase the performance of (electro)catalytic conversions

多孔材料是解决低碳能源需求(二氧化碳减排中的电极)或应对日益严重的环境污染和淡水短缺(用于废水处理的催化膜)的技术的关键组成部分。对于这些应用，需要含有催化金属纳米颗粒等活性物种的高度多孔的复合材料。到目前为止，最先进的制造方法限制了对所产生的多孔结构的控制和对催化活性中心周围化学环境的调节。在该项目中，基于薄膜浇注和后续相分离的制备工艺将进一步朝着能够获得具有定制性能的多孔多复合材料(PMCM)的平台发展。功能粒子和聚合物将为PMCM提供催化活性中心、导电性、吸附中心、离子交换性能以及粒子锚定功能，以实现综合协同效应。在一项已发表的初步工作中，申请人已经展示了聚醚砜基多孔薄膜的合成，其中包括纳米镍、纳米碳和带正电荷的离聚体。根据相分离条件的不同，会形成不同的孔结构，从而获得较高的组分负载量。通过将这些PMCM用作连续降解对硝基苯酚的流通膜反应器，申请者可以证明，碳颗粒和阳离子离子的添加优化了材料中的镍微环境，导致转化频率比单独的镍颗粒高达10倍。碳纳米粒子还将导电性引入到多孔薄膜中，以铜为催化剂的PMCM已经成功地用作二氧化碳电还原的气体扩散电极。在这个项目的开始，这一新的制造工艺将进一步优化，以独立调整材料的形貌和化学成分。特别令人感兴趣的是对这一复杂体系的相分离机制以及不同组分如何融入聚合物基质的研究。生成的PMCM将被用作废水加氢脱氯的催化膜，以及用于电催化二氧化碳还原的电极，重点是使用针对具体应用的材料。此外，该项目还为建立这些新型PMCM作为活性多孔材料奠定了基础，这些材料可以在以后的项目中用作多相催化剂，用于要求苛刻的反应，或者另外用作水电解槽或电池的电极。

Porous materials are key components in technologies that could solve the need for low carbon energy (electrodes in CO2 reduction) or could combat the increasing environmental pollution and fresh water shortages (catalytic membranes for wastewater treatment). For these applications, highly porous composite materials are needed that incorporate active species like catalytic metal nanoparticles. So far, the state-of-the-art manufacturing approaches limit the control over the resulting porous structure and the tuning of the chemical environment around catalytically active sites. In this project, a fabrication process based on film casting and subsequent phase separation will be further developed towards a platform that can access porous multi-composite materials (PMCMs) with tailored properties. Functional particles and polymers will provide the PMCMs with catalytically active sites, electrical conductivity, adsorption sites, ion-exchange properties as well as particle anchoring function for combined synergistic effects. In a published preliminary work, the applicant already showed the synthesis of polyethersulfone based porous thin films that incorporate nickel nanoparticles, carbon nanoparticles and a positively charged ionomer. Dependant on the phase separation conditions, different pore structures were formed and a high component loading was achieved. By employing these PMCMs as flow-through membrane reactors for the continuous degradation of p-nitrophenol the applicant could show that the addition of carbon particles and cationic ionomer optimized the nickel microenvironment in the material which resulted in up to 10 times higher turnover frequencies compared to the individual nickel particles. The carbon nanoparticles also introduced electrical conductivity into the porous thin films and PMCMs with copper as catalyst particles were already successfully used as gas diffusion electrodes for the electroreduction of CO2. In the beginning of this project, this new fabrication process will be further optimized to independently adjust the morphology and chemical composition of materials. Of special interest is the investigation of the phase separation mechanisms of this complex system and how the different components are incorporated into the polymer matrix. The resulting PMCMs will be used as catalytic membranes for the hydrodechlorination of wastewater and as electrodes in the electrocatalytic CO2 reduction with a focus on using application-tailored materials. Furthermore, this project lies the foundation for the establishment of these novel PMCMs as active porous materials that could be used in later projects as heterogeneous catalysts for demanding reactions or additionally as electrodes in water electrolyzers or batteries.