Bai Peiyao, Liu Weiqi, Yang Chuangchuang, Wei Shilin, Xu Lang
MOE Key Laboratory of Coal Processing and Efficient Utilization, School of Chemical Engineering and Technology, China University of Mining and Technology, 1 Daxue Road, Xuzhou, Jiangsu 221116, China.
MOE Key Laboratory of Coal Processing and Efficient Utilization, School of Chemical Engineering and Technology, China University of Mining and Technology, 1 Daxue Road, Xuzhou, Jiangsu 221116, China.
J Colloid Interface Sci. 2021 Apr;587:290-301. doi: 10.1016/j.jcis.2020.12.022. Epub 2020 Dec 11.
Clean energy conversion/storage techniques have become increasingly significant because of the increasing energy consumption. Regarding practical applications like zinc-air batteries and supercapacitors, electrode materials are essential and often require both porous networks and active species to enhance their electrochemical performance. Nitrogen-doped porous carbon (NPC) is a kind of promising material, which provides efficient active sites and large surface areas for energy conversion/storage applications. However, rational modulation of properties for maximizing NPC performance is still a challenge. Herein, a promising NPC material derived from natural biomass is successfully synthesized by following a stepwise preparation method. Physisorption and X-ray photoelectron spectroscopy (XPS) analyses demonstrate both pore structures and nitrogen species of the NPC have been delicately tuned. The optimized sample NPC-800-m exhibits excellent performance in both oxygen reduction reaction (ORR) and three-electrode supercapacitor measurement. Moreover, the homemade zinc-air battery and symmetric supercapacitor assembled with NPC-800-m also display outstanding energy and power density as well as durable stability. Density functional theory (DFT) calculations further confirm the synergistic effects among graphitic, pyridinic and pyrrolic nitrogen. The existence of multispecies of nitrogen combined with the optimized pore structure is the key to the high electrochemical performance for NPC-800-m. This work not only provides feasible and green synthetic methodology but also offers original insights into the effective pores and the synergistic effects of different nitrogen species in the NPC materials.
由于能源消耗不断增加，清洁能源转换/存储技术变得越来越重要。对于锌空气电池和超级电容器等实际应用而言，电极材料至关重要，通常需要多孔网络和活性物质来提高其电化学性能。氮掺杂多孔碳（NPC）是一种很有前途的材料，为能源转换/存储应用提供了高效的活性位点和大表面积。然而，合理调控性能以最大化NPC性能仍然是一个挑战。在此，通过逐步制备方法成功合成了一种由天然生物质衍生的有前途的NPC材料。物理吸附和X射线光电子能谱（XPS）分析表明，NPC的孔结构和氮物种都得到了精细调控。优化后的样品NPC-800-m在氧还原反应（ORR）和三电极超级电容器测量中均表现出优异的性能。此外，用NPC-800-m组装的自制锌空气电池和对称超级电容器也显示出出色的能量和功率密度以及持久的稳定性。密度泛函理论（DFT）计算进一步证实了石墨氮、吡啶氮和吡咯氮之间的协同效应。多种氮物种的存在与优化的孔结构相结合是NPC-800-m具有高电化学性能的关键。这项工作不仅提供了可行的绿色合成方法，还为NPC材料中有效孔隙和不同氮物种的协同效应提供了独到的见解。
