Pinecone-derived biomass carbons as anodes for lithium and sodium-ion batteries by template-assisted and chemically activated approaches

Herein, a new strategy is adopted to synthesize 3D interconnected mesoporous biomass-derived carbon using mesoporous silica as the template. The facile and low-cost route assists to successfully synthesize pinecone-derived carbon using mesoporous silica KIT-6 as template. Three different chemical reagents, i.e., H3BO3, K2CO3 and KOH, are also utilized to prepare chemically activated pinecone-derived carbons separately. When treated as an anode in lithium-ion batteries, the template-assisted pinecone-derived carbon (PDC-T) provides excellent discharge capacities of 822.8 and 272.1 mAh g−1 beyond 500 cycles at current densities of 100 and 1000 mA g−1, respectively. On the other hand, the chemically activated PDC-H3BO3, PDC-K2CO3 and PDC-KOH anodes exhibit corresponding discharge capacities of 571.4, 337.8 and 365.4 mAh g−1 beyond 500 cycles at 100 mA g−1. Additionally, a full cell is constructed to validate the potential applications of pinecone-derived carbons in lithium-ion batteries with long-term cycling stability. In sodium-ion battery, the PDC-T anode delivers superior discharge capacity of 338.9 mAh g−1 at 50 mA g−1. The electrode provides discharge capacities of 271.5 and 103.3 mAh g−1 beyond 500 and 1000 long cycles at 100 and 500 mA g−1, respectively. The present work demonstrates an alternative route to synthesize high-performance biomass-derived mesoporous carbons for rechargeable batteries.