重新定义活性剂对于多孔碳的作用
Yonghui Zhang1,2, Xin Xu1, Qingxuan Geng3
1The State Key Laboratory of Refractories and Metallurgy, Institute of Advanced Materials and Nanotechnology, Wuhan University of Science and Technology Wuhan 430081 China.
Chemical science
|January 6, 2025
概括
这项研究揭示了混合活性如何精确地控制多孔碳的形成. 氧化 (KOH) 启动孔隙形成,而碳酸 (K2CO3) 提炼它们,提高微孔隙性和超级电容器性能.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 物理化学 物理化学
背景情况:
- 性激活是生产多孔碳的标准方法.
- 现有的模型往往过于简化了混合系统中单个的作用,重点是腐蚀性而不是化学机制.
研究的目的:
- 阐明强 (KOH) 和弱 (K2CO3) 在多孔碳的混合活性化中的不同作用.
- 根据内在化学反应重新定义激活途径.
- 为了优化超级电容器应用的多孔碳特性.
主要方法:
- 在现场进行热重量测量质谱 (TG-MS) 分析以追踪反应.
- 密度函数理论 (DFT) 计算以建模反应路径.
- 材料表征技术,以分析多孔碳结构和性能.
主要成果:
- KOH分解为K2O,通过攻击C-C键,启动孔隙形成.
- K2CO3修改了激活路径,CO3^2-首选蚀刻毛孔种子,导致微孔性增加.
- 最佳的1:1KOH:K2CO3比率产生了CK1K2-122 ,其微孔度为82.61%,表面积为1962.18m^2g^-1.
结论:
- 这项研究阐明了KOH和K2CO3在制造量身定制的多孔碳结构中的协同作用.
- 优化的材料表现出极好的超级电容性能,包括高特异电容 (296.7 F g ^ -1) 和能量密度 (114.4 Wh kg ^ -1).
- 这项工作提供了通过受控激活来设计先进的多孔碳的机制理解.
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