Abstract

The objective of this study was to convert biochar, a byproduct generated from the hydrothermal process (in oxygen-limited environment) of biomass (e.g., corn stover), into value-added product. In specific, three-dimensional (3D) biochar-containing precursor sponge, which was made by using electrospun polymer nanofibers as skeleton support, was fabricated via an innovative approach. The weight ratio of biochar to polymer (in the precursor sponge) was 2/1, and it appeared that the biochar weight ratio could be further increased. Upon heat treatments (i.e., stabilization in air and carbonization in argon), the precursor sponge was converted into carbon nanofibrous sponge that had the porosity of ~ 90 vol%, the BET surface area of ~ 51.7 m² g^− 1, and the carbon content of ~ 95 wt%; and it was mechanically elastic/resilient. The electrochemical study indicated that, the carbon nanofibrous sponge could be utilized for making supercapacitor electrode with excellent rate capability and high kinetic performance. This study would not only demonstrate a high-value application of hydrothermally generated biochar, but also provide a facile while novel approach for the fabrication of carbon nanofibrous sponge which could be potentially used for various applications (particularly the energy storage application).

Graphic Abstract

中文翻译：

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由水热生成生物炭和电纺聚合物纳米纤维制成的碳纳米纤维海绵

摘要

这项研究的目的是将生物炭，即从生物质（例如玉米秸秆）的水热过程（在氧气受限的环境中）产生的副产物转化为增值产品。具体而言，通过一种创新的方法，通过使用静电纺丝聚合物纳米纤维作为骨架载体，制作了含有三维（3D）生物炭的前体海绵。生物炭与聚合物的重量比（在前体海绵中）为2/1，看来生物炭的重量比可以进一步提高。经过热处理（例如，在空气中稳定并在氩气中碳化），前体海绵被转化为碳纳米纤维海绵，其孔隙率约为90 vol％，BET表面积约为51.7 m ² g ^-1，碳含量为〜95 wt％；并且具有机械弹性/弹性。电化学研究表明，碳纳米纤维海绵可用于制备超级电容器电极，具有极好的倍率性能和高动力学性能。这项研究不仅将证明水热生成生物炭的高价值应用，而且还将为碳纳米纤维海绵的制造提供一种简便而新颖的方法，该方法可潜在地用于各种应用（尤其是能量存储应用）。

图形摘要