由蜡烛灰制备洋葱状纳米碳及其摩擦学机制研究

Carbon is a key material in the materials science and technology. It has different allotropes that includes graphite, diamond to fullerenes, carbon nanotubes, graphene and graphite alkyne and most of them have been extensively studied in tribology because of the unique self-lubricating and antiwear characteristics. The project will study a novel types of onion-like nano-carbon prepared from the incomplete burning of candles and other materials and the working mechanisms in the interface mechanical shear (friction). Different source materials and combustion atmosphere will be studied to enhance the production yield, optimize the nano-carbon morphology and size distribution. The surface modification approach will be researched to enhance its solubility both in aqueous solution and in different lubricating oils including ionic liquids and to enhance their tribological properties. These modification methods may include surface grafting polymer brush, fluorination and grafting ionic liquids. Their tribological mechanisms will be studied by friction coefficient measurement and observation of boundary lubrication film formation through high-resolution transmission electron microscopy and in-situ Raman spectroscopy and characterization of the wear surfaces and debris. The results will provide theoretical basis and technical guidance to develop new carbon-based nano-additives.

碳材料在材料科学与技术中占有非常重要的地位，从石墨、金刚石到富勒烯、碳纳米管、石墨烯和石墨炔，人们仍在探索碳的新颖结构及新用途。这些碳具有独特的润滑或抗磨特性，故而在摩擦材料中占有重要的地位。本项目将研究通过蜡烛等材料不完全燃烧过程制备洋葱状纳米碳的新方法及其在界面机械剪切（摩擦）作用下的行为机制。研究不同系列原材料和燃烧气氛对纳米碳形貌、尺寸的影响规律，获得高产率、单分散洋葱状纳米碳制备方法；研究后处理对表面化学成分的影响规律，通过表面接枝聚合物刷、氟化、以及离子液体功能化，改善其在水、润滑油和离子液体中的分散性，提高其润滑抗磨性能；通过摩擦系数变化和边界润滑膜形成的实时监测、高分辨透射电镜和原位拉曼光谱等手段对磨损表面和磨屑进行表征，获得在机械剪切下洋葱状碳的作用机制。研究结果将为发展新型洋葱状纳米碳为基础的添加剂提供理论和技术指导。

为了生态环境的可持续发展，绿色、高效、多功能润滑添加剂发展迫在眉睫。洋葱状结构可以有效嵌入运动机械间隙以及在滑动摩擦过程中通过片层剥离而起到润滑抗磨作用。二硫金属化合物可以形成洋葱状纳米结构材料，但其含有的金属和硫元素会增加环境有毒物排放，且制备较困难。本研究针对这一研究背景，发展了一种成本低、步骤简单、绿色环保的新型洋葱状碳纳米材料制备方法。研究了洋葱状蜡烛灰碳纳米颗粒表面衍生化修饰的方法；考察碳纳米颗粒尺寸和形貌对摩擦学性能影响规律；考察添加量对摩擦学性能的影响，优化其最佳配比。深刻揭示碳纳米颗粒结构与摩擦学性能关系规律。研究揭示洋葱状碳纳米颗粒作为添加剂减摩抗磨作用机制。研究为开发洋葱状纳米碳添加剂产品具有重要的理论指导意义和应用价值。在Chem Comm，ACS Appl Mater Interf，Adv Mater Interf 和 Wear，Tribol Lett 等摩擦学专业学术期刊已接受发表SCI论文14篇，EI论文2篇，共发表论文16篇。