Related Experiment Video
Updated: Jul 24, 2025

Experiments on Ultrasonic Lubrication Using a Piezoelectrically-assisted Tribometer and Optical Profilometer
Published on: September 28, 2015
Partially Oxidized Violet Phosphorus as an Excellent Lubricant Additive for Tribological Applications
Yunze Li1, Kai Gao1, Yi Zhang1
1State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, People's Republic of China.
Abstract:
As a novel two-dimensional material, violet phosphorus (VP) has attracted a considerable amount of attention due to its high carrier mobility, anisotropy, wide band gap, stability, and easy stripping properties. In this work, the microtribological properties of partially oxidized VP (oVP) and the mechanism of reducing friction and wear as additives in oleic acid (OA) oil were studied systematically. When adding oVP to OA, the coefficient of friction (COF) decreased from 0.084 to 0.014 with the steel-to-steel pair, and the ultralow shearing strength tribofilm consisting of amorphous carbon and phosphorus oxides that formed resulted in the reductions of COF and wear rate individually by 83.3% and 53.9%, respectively, compared with those of pure OA. The results extended the application scenarios for VP in the design of lubricant additives.
Related Concept Videos
Oxidation of Phenols to Quinones
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
Redox Titration: Other Oxidizing and Reducing Agents
Aldehydes and Ketones to Alkenes: Wittig Reaction Mechanism
The reaction begins with the nucleophilic addition between a phosphorus ylide and the carbonyl compound. Due to its carbanionic character, phosphorus ylide acts as a strong nucleophile and attacks the electrophilic carbonyl group. This generates a charge-separated dipolar intermediate called betaine. The negatively charged oxygen atom and...
Design Example: Deciding Thickness of Lubricating Fluid in a Shaft
To calculate the required thickness of the lubricant layer, the tangential velocity at the shaft's surface must first be determined. This velocity is calculated by converting the rotational speed to angular...
Photoluminescence: Applications
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate

