Gradient‐Integrated High‐Strength and High‐Toughness Cellulose Triboelectric Materials for Enhanced Charge Storage and Transport

The rapid advancement of wearable electronics places ever‐increasing demands on the electrical and mechanical properties of materials. Cellulose offers renewability, low cost, and high durability for green wearables, but its weak electron‐donating ability and poor charge‐transport efficiency limit triboelectric performance. Interfacial mismatch between the electrode and triboelectric layers also induces charge dissipation, further aggravating this problem. Inspired by the Janus structure found in sea urchin spines, a gradient‐integrated triboelectric material (MWCNT/T‐CNFs) was fabricated via vacuum‐assisted layer‐by‐layer filtration. The resulting gradient electric field forms a highly compatible interface between the triboelectric layer and the electrode layer, providing a low‐impedance path that effectively suppresses charge dissipation. Consequently, the material achieves a surface charge density of 20.5 nC cm −2 (931.8% that of pure T‐CNFs) and excellent cycling stability (8044 cycles). The integrated interface offers strong adhesion, far outperforming conventional electrode tapes, while the gradient design alleviates stress concentration, yielding a tensile strength of 126.33 MPa and toughness of 9.11 MJ m −3 (535.9% that of pure T‐CNFs). The material also exhibits good water stability and high‐temperature resistance. This study addresses the key limitations of low surface charge density and interfacial mismatch in cellulose materials, providing a solid foundation for interface design in wearable electronics.