Porous N, O, S‐Doped Carbon from Feathers Drives pH‐Universal H 2 O 2 Electroproduction

Abstract Harnessing the two‐electron oxygen reduction reaction (2e − ORR) pathway for electrochemical H 2 O 2 production offers a sustainable alternative to the anthraquinone process, yet the development of low‐cost, efficient, and pH‐universal catalysts remains a formidable challenge. In this work, we propose a sustainable solid‐waste‐to‐catalyst route that converts keratin‐rich feather waste into chicken‐feather‐derived carbon‐3 (CFDC‐3)—a hierarchical, N, O, S‐doped porous carbon—via high‐temperature alkaline activation. The CFDC‐3 features abundant micro/mesopores, ultrahigh surface area, and defect‐rich multi‐heteroatom sites, delivering excellent H 2 O 2 selectivity (≈95% in acidic, ≈90% in neutral media) and strong durability. Electrochemical tests, in situ spectroscopy, and theoretical calculations reveal that the synergy of dopants, defects, and porosity optimizes the electronic structure, enhances O 2 adsorption, and promotes the 2e − ORR pathway. When integrated into a flow cell with acidic electrolyte, CFDC‐3 delivers a high H 2 O 2 yield of 4187 mg L −1 h −1 and ≈80% Faradaic efficiency. Moreover, in a two‐electrode solid‐state system, it enables continuous generation of ≈6.65 wt.% H 2 O 2 over 21 h, while solar‐driven electrolysis rapidly accumulates 2.81 wt.% within 1 h. This work demonstrates a waste‐to‐catalyst strategy that converts feather‐derived keratin into defect‐rich, heteroatom‐doped porous carbon, offering a scalable and sustainable platform for efficient H 2 O 2 electrosynthesis.