Extrusion-based additive manufacturing of three-dimensional MoSe2-nanosheet-coated TiO2 hetero-structures for photocatalytic CO2 reduction

Abstract

Extrusion-based additive manufacturing (EAM) provides design freedom and facilitates the production of complicated structures that are often challenging to produce using conventional processing methods. In this study, a TiO 2 feedstock was developed by mixing TiO 2 with a binder and optimized for extrusion. To maximize the reaction e ciency, we fabricated three-dimensional (3D) structures for photocatalytic CO 2 reduction based on the designed model. To further enhance the photocatalytic CO 2 reduction e ciency, we introduced a heterostructure by hydrothermally synthesizing MoSe 2 , a transition metal dichalcogenide (TMD), on the TiO 2 surface. MoSe 2 , which is known for its affordability in fabrication heterostructures, high electrical conductivity, expanded light absorption range, and reduced bandgap, has the potential to enhance photocatalytic e ciency. The effectiveness of various TiO 2 -MoSe 2 3D structural designs for CO 2 reduction was evaluated. A custom-made stainless-steel reactor was used for CO 2 reduction under UV-vis irradiation, followed by gas chromatography analysis of the produced gases. The optimized structure exhibited remarkable CO 2 selectivity, reaching approximately 82%, demonstrating the feasibility of using EAM for fabricating 3D structures for photocatalytic CO 2 reduction.