Overcoming the Activity-Stability Trade-Off in Heterogeneous Electro-Fenton Catalysis: Encapsulating Carbon Cloth-Supported Iron Oxychloride within Graphitic Layers

Maintaining a long-term service life of catalytic materials under the established configuration and design concept is a key focus in catalytic process research and development, especially for iron-functionalized cathode-based heterogeneous electro-Fenton (EF) processes operated under harsh conditions. Herein, a versatile and robust encapsulation engineering strategy is proposed based on the concept of tightly covering the surface of conventional iron-functionalized cathodes with an ultrathin carbon layer to significantly improve the stability of composite cathodes without causing activity loss. Taking carbon cloth-supported iron oxychloride (FeOCl/CC) as a model cathode catalyst, it was successfully encapsulated in a reduced graphene oxide protective shell (FeOCl/CC@rGO) using an electrophoretic deposition method, thereby achieving high stability due to negligible iron leaching (only 0.57% of FeOCl/CC), while maintaining almost unaffected activity due to electron penetration effect. Experimental analysis of the structure-activity relationship and theoretical calculations were used to establish the underlying molecular mechanism of electron penetration-triggered H2O2 activation on the outermost surface of rGO. This study uses an effective approach to overcome the activity-stability trade-off of integrated cathodes in heterogeneous EF processes, providing theoretical guidance for the rational design of high-performance cathodes with an encapsulated structure.

Automated summary

In this study, a encapsulation engineering strategy is proposed to improve the stability of composite cathodes without causing activity loss. By tightly covering the surface of traditional cathodes with an ultrathin carbon layer, the composite cathodes achieved high stability and maintained almost unaffected activity. Experimental and theoretical analysis revealed the underlying mechanism of electron penetration-triggered activation.