Highly graphitized porous biocarbon nanosheets with tunable Micro-Meso interfaces and enhanced layer spacing for CO₂ capture and LIBs

Porous carbon materials with tunable micro and mesoporous structure, graphitic wall structure, and enhanced layer spacing are considered attractive materials for several applications, including adsorption and energy storage and conversion. However, it is challenging to design porous carbon with all these properties in a single system. Here, we present a facile and rational synthesis route to fabricate graphitized porous biocarbon nanosheets from a low-cost precursor through a simple integration of simultaneous “activation and graphitization” process using iron acetate and potassium acetate at a high temperature. The prepared materials show tunable micro and mesoporosity with an enhanced layer spacing and high crystallinity. These sophisticated materials exhibit a smooth switch over the micro and mesopores for either low (5.9 mmol g⁻¹/ 0 °C/ 1 bar) or high pressure (16.7 mmol g⁻¹/ 0 °C/ 30 bar) CO₂ capture. The careful manipulation of the porous texture and the graphitization degree also allows for enhanced performance as LIB anodes (646 mAh g⁻¹), which show good cycling and surpass the specific capacity of conventional graphite anode (372 mAh g⁻¹). These findings exemplify the importance of designing intriguing materials for addressing climate change by reducing greenhouse gases as well as providing low-cost alternative energy storage resources.