Preparation and tribological properties of lanthanum-doped TiO2 nanoparticles in rapeseed oil |
| |
Authors: | GU Kecheng CHEN Boshui CHEN Yong |
| |
Affiliation: | 1. Department of Oil Application & Management Engineering, Logistical Engineering University, Chongqing 401311, China; 2. Department of Barracks Management & Environmental Engineering, Logistical Engineering University, Chongqing 401311, China) |
| |
Abstract: | Oleic acid (denoted as OA) surface-capped lanthanum-doped titanium dioxide composite nanoparticles, abbreviated as OA/La-TiO2, were prepared via sol-gel method in association with surface modification by oleic acid. The microstructure of as-prepared OA/La-TiO2 was characterized by means of X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectrometry, and their thermal stability was evaluated by thermogravimetry and differential scanning calorimetry. Moreover, the tribological properties of OA/La-TiO2 as lubricant additives in rapeseed oil were evaluated with a four-ball friction and wear tester. The morphology as well as elemental composition and chemical characteristics of worn steel surfaces was investigated by scanning electron microscopy, energy dispersive X-ray spectrometry and X-ray photoelectron spectroscopy. Results showed that as-prepared OA/La-TiO2 particles were of spherical shape and had an average diameter of 20 nm. In the meantime, OA/La-TiO2 particles doped with 1.5% (molar ratio; the same hereafter) and 2.5% of lanthanum could markedly improve the anti-wear and friction-reducing capacities of rapeseed oil. This is attributed to the formation of a complex boundary lubrication film mainly composed of the oxides of iron, titanium and lanthanum as well as the formation of an adsorption film of oleic acid on steel sliding surfaces. |
| |
Keywords: | titanium dioxide lanthanum nanoparticle preparation rapeseed oil lubricant additive tribological properties rare earths |
本文献已被 CNKI 维普 万方数据 ScienceDirect 等数据库收录! |
|