Title : Structured multilayer thin films for catalytic applications: A novel approach on catalyst design utilizing microfabrication techniques
Abstract:
The interface between metal nanoparticle and oxide support is often identified to play a crucial role in heterogeneous catalysts. Traditional semiconductor fabrication techniques, such as RF sputtering and laser scribing enable targeted design and optimization of bi-functional catalytically active interfaces.
In this study, we present a novel approach to tailor the accessible interface of bi- functional materials for heterogenous reactions, which aims to enhance the density of active sites at the surface of the catalyst. As a model system for this approach, using thin film technology, we create a multilayer structure comprised of hundreds of alternating layers of copper and zinc oxide films. To expose the Cu/ZnO interface considered to be the imperative for methanol synthesis, a pico-second laser is used for selective material ablation, creating defined chasms or holes in the otherwise closed structure. To streamline multilayer deposition, RF magnetron sputtering was conducted using a specially designed split target, combining two semicircular targets of Cu and ZnO, eliminating the complexity and time involved in sequential layer deposition with separate targets. Before and after laser scribing SEM images show well-defined distinct Cu and ZnO layers, thus confirming the successful fabrication of discrete layers and the mechanical stability of those. The fabricated multilayer catalyst demonstrated CO? conversion of 0.45% at 290°C, corresponding to a methanol production rate of 1.16 × 10?² µmolMeOH / h-minterface , confirming the feasibility of thin-film catalysts for fundamental studies as well as industrial applications. The current work shows, to the best of our knowledge, for the first time, the use of advanced deposition techniques in combination with laser scribing as a method for fabricating structured multilayer materials for precise interfacial engineering, proposing a novel concept for the design of tailored heterogenous catalysts. This presentation will discuss the design, fabrication, and performance of Cu-ZnO multilayer catalysts, emphasizing the advantages of microfabrication techniques in catalyst engineering. The findings pave the way for scalable, high-performance catalytic systems with tailored interfaces, offering new opportunities for energy-efficient chemical processes.
