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The goal of this dissertation was to evaluate the catalytic performance of metal oxide structured catalysts with optimized geometries prepared via 3D printing for the efficient conversion of carbon dioxide to useful energy products. Three-dimensional (3D) printing, also known as additive manufacturing, is a fabrication method that creates structures from digital models. Despite the profound impact that 3D printing has had in many fields, its application in the production of catalysts, which are typically metal or metal oxide structures of high complexity with chemical functionalities, is still in its early stages. In the context of circular economy, carbon capture and utilization (CCU) technologies represent an outstanding opportunity to capture and convert carbon dioxide into valueadded materials. One particularly appealing product is dimethyl ether (DME), which can be used as a fuel substitute in transport with reduced environmental impacts relatively to conventional fuels. This thesis consists of the detailed characterization of the physiochemical properties of the catalysts with various methods and the evaluation of their performance in the direct CO2 to DME conversion under various operating conditions. The primary findings of this study demonstrated that commercial catalysts in powder form outperformed 3D-printed catalysts in terms of CO2 conversion and product yields. Despite the monoliths’ considerably lower activity their increased DME selectivity is promising. Future research is advised to further understand the limitations of the 3D printed catalysts and discover the opportunities to improve their performance. The experimental work related to the characterization of the physicochemical properties and the evaluation of the catalytic performance was conducted at the Laboratory of Environmental Fuels and Hydrocarbons (LEFH) in CPERI/CERTH, in Thermi Thessaloniki. This dissertation was written as part of the MSc in Energy and Finance at the International Hellenic University.