Exploiting its exceptional structural tunability and digital manufacturing capability, 3D printing emerges as a transformative technique for the rational design and scalable fabrication of catalytic electrodes tailored for advanced electrochemical energy systems. In this study, hierarchically porous, self-supporting carbon electrodes were fabricated via 3D printing technique in combination with the sequential conformal carbonization. An optimized polymerizable ionic liquid-based ink was employed to produce a 3D printed polymer gel, which was subsequently functionalized with B-containing species. The as-prepared gel was then pyrolyzed to yield B/N-co-doped carbon electrodes with a high surface area possessing micropores, mesopores and macropores. The metal-free cathode demonstrated good performance in electrocatalytic CO₂ reduction, producing syngas with tunable H₂/CO ratios ranging from 0.37 to 2.6, thereby catering to diverse application requirements. This study naturally integrates 3D printing with ionic-liquid chemistry to fabricate customizable metal-free carbon electrodes for efficient CO₂-to-syngas conversion, offering a Power-to-X route to store intermittent renewable electricity as chemical energy and to deliver tunable H₂/CO syngas suitable for downstream fuel and chemical synthesis.