Three-Dimensional Porous Copper Conductive Paper

Conductive paper promises benefits in flexible biodegradable electronics and sustainability but faces challenges in its conductivity, stress-bearing, hierarchical manufacturing, and integration with existing technologies. Herein, we report self-reducing and grafting copper onto paper cellulose fiber networks activated through a nonequilibrium photonic approach. A three-dimensional volumetric paper conductor exhibits a sheet resistance of 5 Ω/square, hydrophobicity with a water contact angle of 95°, and tailored thermal emissivity for thermal management. Furthermore, the cellulose-Cu network conductor facilitated the infiltration of silicon during lithiation and acted as a buffer to mitigate mechanical failure due to capillary action. Interestingly, the cellulose-Cu-silicon paper conductors achieved real-time pressure monitoring during the (de)lithiation cycles. Three-dimensional porous structured paper conductors demonstrate the potential for integrating electronic and ionic transport as flexible biodegradable battery electrodes with real-time pressure sensing.