Structured Multilayer Thin Films for Catalytic Applications: A Novel Approach on Catalyst Design Utilizing Microfabrication Techniques

Abstract

The metal/metal oxide interface is key to establishing catalytic performance, selectivity, and stability in heterogeneous systems. In this proof‐of‐concept study, a systematic methodology is introduced for the preparation of multilayer catalysts that combines Radio Frequency (RF) magnetron sputtering with laser microstructuring for the synthesis of high‐density Cu/ZnO interfaces. By means of a specifically designed split target, alternating few‐nanometer‐thick layers of Cu and ZnO are deposited under precise control and with high reproducibility. Laser scribing is then employed to create defined microstructures that reveal buried interfaces, improving access to catalytically active interfaces. As‐deposited and laser‐scribed multilayer's structural and chemical stability is confirmed through Atomic Force Microscopy (AFM), X‐Ray Fluorescence (XRF), X‐Ray Diffraction (XRD), X‐Ray Photoelectron Spectroscopy (XPS), and Scanning Electron Microscope (SEM) characterizations. Catalytic activity is evaluated under gradient‐free, continuous‐stirring conditions for CO2 hydrogenation to methanol where the catalyst produces methanol and CO under laboratory‐scale conditions. The strategy addresses specific design bottlenecks such as limited control over interfacial geometry and exposure while acknowledging the inherent limitations of thin‐film systems in terms of surface area and scalability. While demonstrated for CO2‐to‐methanol conversion, the method is generally applicable to other interface‐dependent reactions. Building on this initial demonstration, forthcoming efforts will focus on detailed mechanistic analysis, long‐duration testing, and performance benchmarking against conventional powder‐based catalysts.