Construction of wood-PANI supercapacitor with high mass loading using "pore-making, active substance-filling,...

Wood-conducting polymer materials have been widely used as supercapacitor electrode; however, it remains challenging to achieve a simple method to improve the homogeneity of the conductive material on wood and to reach high mass loading. Herein, a novel "pore-making, active substance-filling, densification (dissolution, in-situ polymerization of polyaniline (PANI), self-shrinking)" strategy is proposed for the preparation of wood electrodes with a high mass loading (41.4 wt%) and homogeneity. Ingeniously, ZnCl₂ as a dissolving agent and pore-making agent to treat delignified wood can generate more pores on the wood, which is more conducive to the penetration of aniline small molecules, besides, the dissolved fine fibers can be entangled with more PANI, which can improve the loading and homogeneity of PANI. After drying treatment, there will be shrinkage again, playing a certain physical densification effect on the large lumen. The optical electrode was RWP2 showing high electrochemical performance (2328.9 mF/cm², 1 mA/cm²), and stability (5000 cycles, 89.3 %). Moving forward, the RWP2//RWP2 SSC showed an excellent energy density of 164.24 μwh/cm² at a power density of 250 μw/cm². Remarkably, the simple and versatile strategy of designing wood-based materials with high mass loading provides new research ideas for realizing multifunctional applications.