Electrochemical urea synthesis

Enabling the electrification of the chemical industry is crucial for the sector's transition toward zero emissions and a sustainable future. Approximately 2% of the globally used energy is dedicated to fertilizer production, including urea. The electrochemical synthesis of urea from a nitrogen source and CO 2 based on renewable energy can contribute to reaching the ambitious goal of sustainable production with close to zero emissions. However, the current state of technology remains at a low readiness level and a small scale. The majority of studies in the field employ electrode surface areas in the order of 1 cm 2 and achieve moderate current efficiencies of < 50%. They are mostly operated in batch mode in H-cells, which are prone to mass transport limitations, leading to a restriction of the achievable current density. In this perspective, we analyze the main challenges regarding highly efficient and scalable reactors for continuous production. We identify knowledge gaps and potential pitfalls. Finally, we propose guidelines to rapidly bridge the gap between fundamental research and industrial application.