Pulsed Electrocatalysis Driven Efficient Ammonia Synthesis by Facilitating *NOOH Formation and Balancing *H Supply

Electrochemical nitrate reduction emerges as a promising approach for ammonia generation; however, its efficiency is hindered by the sluggish hydrogenation of nitrogen-containing intermediates and limited active hydrogen supply at constant applied potentials. Driven by the pulsed electrocatalysis, in this work, efficient nitrate-to-ammonia conversion is realized by facilitating *NOOH formation and balancing *H supply on a Janus Cu@Co/NC electrocatalyst. In detail, the Cu sites could activate NO₃ ^- at low overpotentials, while the Co sites could facilitate *NOOH formation with sufficient *H provided by the Co sites at high overpotentials. Promoted by the pulsed electrocatalysis technique, a maximum Faradaic efficiency of 98.32% with NH₃ yield rate of 12.75 mg h^-1 mg_cat ^-1 is attained, and the scaled-up pulsed electrosynthesis at industrial current densities is also achieved. This work underlines the feasibility of pulsed electrolysis for regulating intermediate hydrogenation, offering a promising approach for the synthesis of ammonia or other important chemicals.