The synthesis of high-valued carbon nanomaterials from biomass has always been a hot topic. The work reports the preparation of hollow carbon nanospheres (HCNs) from potato starch with one-step carbonization, in which self-made MgO powder is utilized as the template. In this study, an attempt was made to change carbonization temperature to control HCNs in diameter, wall thickness and pore distribution. Results show that the sample obtained at 800 °C (HCN-800) has a thinner wall thickness (about 12.1 nm), smaller and more uniform diameter (average diameter of 46.2 nm), as well as possesses a high specific surface area (619.53 m g) and the largest pore volume (2.8994 cm g). An application in supercapacitor has been verified for the HCNs in the work. In the three-electrode system, the HCN-800 exhibits excellent electrochemical performance, such as superior specific capacitance (324.8 F g at 0.5 A g), high rate performance (215.7 F g at 50 A g) and outstanding cycling stability (92.83 % capacitance retention after 10,000 cycles). Moreover, an assembled symmetric supercapacitor shows an energy density of 11.1 Wh kg at a power density of 427 W kg, far exceeding that of previously reported carbon electrode materials. In short, the work provides a novel way to synthesize high-value-added HCNs from cheap biomass precursors, which have potential applications in the field of supercapacitors and other energy storage devices.

中文翻译：

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马铃薯淀粉中空碳纳米球的合成及其在超级电容器中的应用


利用生物质合成高价值碳纳米材料一直是研究热点。该工作报道了以自制的氧化镁粉末为模板，通过一步碳化法制备了马铃薯淀粉中空碳纳米球（HCNs）。本研究尝试通过改变碳化温度来控制HCN的​​直径、壁厚和孔隙分布。结果表明，在800 ℃下获得的样品（HCN-800）具有更薄的壁厚（约12.1 nm）、更小且更均匀的直径（平均直径为46.2 nm），并且具有较高的比表面积（619.53 mg）和最大孔容（2.8994 cm g）。工作中已经验证了 HCN 在超级电容器中的应用。在三电极体系中，HCN-800表现出优异的电化学性能，如优异的比电容（0.5 A g-1时为324.8 F g）、高倍率性能（50 A g-1时为215.7 F g）和出色的循环稳定性（92.83 %） 10,000 次循环后的电容保持率）。此外，组装的对称超级电容器在功率密度为427 W kg时表现出11.1 Wh kg的能量密度，远远超过先前报道的碳电极材料。简而言之，这项工作提供了一种从廉价生物质前驱体合成高附加值HCN的新方法，在超级电容器和其他储能设备领域具有潜在的应用前景。