Li–Na metal compounds inserted into porous natural wood as a bifunctional hybrid applied in supercapacitors and electrocatalysis.

As a green and sustainable natural resource, wood is regarded as a feasible candidate material for developing green and sustainable energy due to its natural porous structure. However, the conductivity of wood is poor, which restricts its application in energy storage. In this research, a novel material with Li–Na metal compounds inserted into porous carbonized lignin free wood (PCLFW) as a bifunctional hybrid is synthesized. This material with a high specific capacitance, high power density and excellent electrocatalytic activity is synthesized. The final product shows a high specific capacitance of 255 F g−1, high energy density of 31.88 Wh kg−1 and power density of 3188 W kg−1. Moreover, after experiencing 5000 cycles, the specific capacitance is maintained at 239 F g−1 (capacitance retention of 93%). In addition, the hybrid exhibits excellent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activities in alkaline solution, with overpotentials of 349 mV (Tafel = 192 mV dec−1) and 484 mV (Tafel = 184 mV dec−1), respectively. Meanwhile, the hybrid also shows a larger initial and half-wave potentials of −0.12 V and −0.22 V, reflecting an outstanding oxidation-reduction reaction (ORR) property. In a word, this work provides a new idea for us to fabricate wood-based hybrid for high-performance energy storage devices and carbon-based catalysts. • Wood inserted metal compounds shows good energy storage and catalysis performance. • Porous wood makes electrolyte ions easier to transport and store. • Li–Na charge transfer channel keeps composite at a higher charge and discharge level. • It provides a new reference for developing high value-added biomass resources. [ABSTRACT FROM AUTHOR]