Ascorbic Acid Derivatives‐Mediated Synthesis of Seaweed‐Like Gold Nanosheets for Enhanced Ethylene Glycol Electrooxidation

Kinetic control is pivotal in directing the nucleation and growth of noble metal nanocrystals with tailored morphologies, where the judicious selection of reductants offers a powerful lever to govern these processes. We present a green, ascorbic acid derivative‐mediated strategy to synthesize ultrathin gold (Au) nanosheets with a hierarchical seaweed‐like architecture, engineered to enhance ethylene glycol electrooxidation. Capitalizing on the dual role of ascorbic acid derivatives as reductants and morphology‐directing agents, we achieve anisotropic growth of Au nanostructures, yielding interconnected porous nanosheets rich in lattice defects and ultrathin edges. Electrochemical studies reveal that the carbon‐supported seaweed‐like Au nanosheets exhibit a 2.7‐fold higher mass activity and a 202 mV lower onset potential compared to their quasispherical counterparts, together with satisfactory stability after 3000 s of chronoamperometry. Density functional theory calculations unveil that higher OH coverage arising from confinement of hierarchical nanostructures significantly facilitating the reaction process. This study not only demonstrate the effective role of reductant on rational synthesis of 2D noble metal nanostructures with exotic shapes but also advances a universal blueprint for designing high‐performance electrocatalysts through strain modulation and morphological precision.