Fig. 2: Performance evaluation.

a Screening of electrode materials with stearic acid (0.3 mmol), KOH (1.2 equivalents), n-Bu₄NPF₆ (0.06 M), EtOH (20 mL) and voltage of 3.5 V. b Yield of n-heptadecane from 1-heptadecene hydrogenation using Pt/C and carbon as the cathode in EtOH under otherwise same conditions. c Hydrogenation barrier of olefins as a function of H–H distance, ranging from 0.74 Å (H₂ molecule) to 1.32 Å (two separated H atoms). d Productivity of olefins under different voltages and different moles of fatty acid at 3.5 V. e H₂ input-free performances of electrochemically coupled decarboxylation and hydrogenation at different voltages with stearic acid (0.3 mmol), KOH (1.2 equivalents), n-Bu₄NPF₆ (0.06 M), EtOH (20 mL). The voltage was not iR corrected. Source data for Fig. 2 are provided as a Source Data file.