Preparation of Semi‐Coke‐Based Porous Graphitic Carbon–Iron Oxide Composites and Their Electrochemical Performance for Rhodamine B Degradation

In response to the demand for clean production and high value‐added utilization of waste semi‐coke (SC) powder, SC‐based porous graphitic carbon–iron oxide (SPC‐Fe) composites were synthesized using a one‐step method with K 2 FeO 4 . The synthesis process primarily depends on the mass ratio of SC to K 2 FeO 4 and the calcination temperature. Under optimal conditions, specifically at a mass ratio of 1:2 (SC/K 2 FeO 4 ) and a calcination temperature of 800°C, SPC‐Fe exhibits a specific surface area of 443.664 m 2 /g, a total pore volume of 0.283 cm 3 /g, and a micropore volume of 0.102 cm 3 /g. It demonstrates excellent double‐layer capacitance performance and outstanding fast charging and discharging capabilities. Moreover, SPC‐Fe functions effectively as a particle electrode and a catalyst for removing Rhodamine B (RhB) from wastewater. This process involves a three‐dimensional electrochemical‐Fenton mechanism, where the high catalytic activity for RhB removal is primarily attributed to the generation of hydroxyl radicals in the system. Experimental results indicate that the RhB removal is more effective in acidic conditions, achieving a removal rate of 96.69% at pH = 2 within 15 min. This study highlights a promising approach for producing high‐performance, cost‐effective carbon compounds from waste SC powder for electrochemical applications.