Carbon-based metal-free nanomaterials for the electrosynthesis of small-molecule chemicals: A review

• Carbon-based metal-free catalysts (CMFCs) offer a cost-effective and stable alternative to noble metal catalysts for electrosynthesis, addressing key limitations in scalability and sustainability. • The review systematically covers design strategies and catalytic mechanisms of CMFCs, highlighting their tunable structures and compositions for enhanced performance. • CMFCs are effective in synthesizing small-molecule chemicals such as hydrogen peroxide, ammonia, and chlorine, as well as various carbon- and nitrogen-based compounds. • Despite progress, challenges remain in improving selectivity and activity; future prospects include advanced material engineering and mechanistic understanding.