Unveiling the quantification minefield in electrocatalytic urea synthesis

• Investigations of urea detection methods in current electrosynthesis system. • Comprehensive evaluation of different urea detection methods. • Rigorous test protocol for urea quantification and the data reports. Electrochemical synthesis of urea from carbon dioxide and nitrogenous species is a promising sustainable strategy, which can be easily incorporated into distributed renewable energy systems. However, a low concentration of urea produced in a complex solution environment brings challenges to its accurate quantification. Here an overall comparison (e.g., accuracy, reliability, anti-interference ability) of the frequently-used determination methods is provided after considering the potential interference factors. Besides, a rigorous urea detection flowchart and a recommended standard are established to achieve a more accurate and responsible performance evaluation in electrocatalytic urea production. This work guides the reliable quantification in urea synthesis, especially at a low concentration within a complicated electrocatalytic system.