Abstract
Electrosynthetic C–X (X = N, S, P) bond formation from abundant small molecules (H2O, CO2, N2, SO32− and PO43−) provides a potential platform for clean-chemical technology. However, under conventional static electrolysis, C–X coupling reactions typically suffer from narrow product scope (dominated by urea), moderate current efficiencies (<50%), catalyst restructuring and uncertain techno-economic viability. In this Review, we describe how pulsed electrolysis enables C–X electrosynthesis through different reaction modes, including oxidative, reductive and oxy-reductive synthesis. Pulsed operation could overcome the key limitations of static electrolysis by continuously regenerating active sites, synchronizing reactive C- and X-derived intermediates, and periodically mitigating depletion, flooding and salt precipitation. These effects could expand the product scope beyond urea to amides, amines, C–S and C–P products, enhance selectivity by 20 times, and enable hundreds of hours of stable operation. The techno-economics of formamide synthesis further indicate that pulsed redox electrolysis can reduce the production costs relative to steady-state operation by enabling reaction pathways inaccessible under static conditions. Translating pulsed C–X electrosynthesis into clean-technology platforms for organonitrogen, organosulfur and organophosphorus chemicals will require predictive, time-dependent microkinetic transport models, data-driven pulse optimization, and reactor and membrane designs tolerant to alternating ion migration.