Pine sawdust derived ultra-high specific surface area activated carbon: Towards high-performance hydrogen storage and supercapacitors

Abstract

Activated carbon has potential in energy storage and conversion, however, conventional methods often struggle to enhance specific surface area and control pore structure precisely, hindering its application in hydrogen storage and electrochemical fields. Therefore, this study aims to utilize pine sawdust as carbon precursor and employ “restricted activation” technology to regulate the specific surface area and pore structure of carbon materials, thereby enhancing their performance in hydrogen and electrochemical energy storage. Results demonstrate activated carbon's exceptional microporous structure and specific surface area, leading to outstanding hydrogen storage (achieving a capacity of 7.73 wt% at 77 K and 40 bar) and electrochemical properties (with the highest energy density of 12.92 Wh∙kg−1 and power density of 125 W kg−1). A comprehensive array of contrasting results has revealed that while micropores experience single-layer adsorption, the engagement of certain micropores and small mesopores in the physical adsorption process markedly boosts hydrogen storage capacity. This investigation sheds light on the relationship between material structure and storage performance, offering insights into multifunction carbon materials for high-capacity hydrogen storage and superior electrochemical performance.