Incorporating Metal Precursors towards a Library of High-resolution Metal Parts by Stereolithography

• A new metal AM method using DLP printed metal precursors realizes metal/alloy components with fine feature size, large dimension, robust structure, and promising properties. • DLP was leveraged to create a robust structure with high resolution. • As-fabricated 3D printed metals have been demonstrated to possess excellent electric and mechanical properties with low surface roughness. Additive manufacturing (AM) of three-dimensional (3D) metals with intricate fine features and complex geometry at the macro- and micro- scale for energy generation and storage has attracted great interest recently. Fabrication of metals using state-of-art powder-based AM technology with high resolution and tunable microstructure remains a challenge. In this work, a new method for achieving sophisticated metallic structure via the digital light process (DLP) of metal precursors containing photo-resin followed by thermal heating and chemical reduction process is presented. Thermal decomposition of 3D-printed metal compound and chemical reduction makes it promising to synthesize a morphology-tunable and geometrically complex metal, alloy, metal oxide, or multi-material component. Two potential applications of 3D-printed copper using this method are demonstrated in the electrochemical field as oxygen evolution reaction (OER) catalyst support and current collector. NiFe hydroxide@3D-printed copper can drive a 100 mA/cm 2 stably with a low energy barrier in an alkaline solution. Galvanostatic cycling profile of DLP Copper/electrolyte/Li at current densities of 2 mA/cm 2 , 4 mA/cm 2 and 10 mA/cm 2 can be conducted stably for a capacity of 20 mA·h/cm 2 . This work is the first to realize metal-based printing with ultra-high resolution thorough photopolymerization.