title: Synergistic effects between phosphonium-alkylphosphate ionic liquids and zinc dialkyldithiophosphate (ZDDP) as lubricant additives.
abstract: Unique synergistic effects between phosphonium-alkylphosphate ionic liquids (ILs) and zinc dialkyldithiophosphate (ZDDP) are discovered when used together as lubricant additives, resulting in significant friction and wear reduction along with distinct tribofilm composition and mechanical properties. The synergism is attributed to the remarkably 30-70× higher-than-nominal concentrations of hypothetical new compounds (via anion exchange between IL and ZDDP) on the fluid surface/interface.
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, P. O. Box 2008, MS-6063, Oak Ridge, TN, 37831-6063, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Qu
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, P. O. Box 2008, MS-6063, Oak Ridge, TN, 37831-6063, USA.
authors.forename: William C
authors.initials: WC
authors.lastname: Barnhill
authors.affiliation: Energy and Transportation Science Division, Oak Ridge National Laboratory, P. O. Box 2008, MS-6181, Oak Ridge, TN, 37831-6181, USA.
authors.forename: Huimin
authors.initials: H
authors.lastname: Luo
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, P. O. Box 2008, MS-6063, Oak Ridge, TN, 37831-6063, USA.
authors.forename: Harry M
authors.initials: HM
authors.lastname: Meyer
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, P. O. Box 2008, MS-6063, Oak Ridge, TN, 37831-6063, USA.
authors.forename: Donovan N
authors.initials: DN
authors.lastname: Leonard
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, P. O. Box 2008, MS-6063, Oak Ridge, TN, 37831-6063, USA.
authors.forename: Alexander K
authors.initials: AK
authors.lastname: Landauer
authors.affiliation: Technology Center Houston, Shell Global Solutions, Houston, TX, 77082-3101, USA.
authors.forename: Bassem
authors.initials: B
authors.lastname: Kheireddin
authors.affiliation: Technology Center Houston, Shell Global Solutions, Houston, TX, 77082-3101, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Gao
authors.affiliation: Technology Center Houston, Shell Global Solutions, Houston, TX, 77082-3101, USA.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Papke
authors.affiliation: Chemical Sciences Division, Oak Ridge National Laboratory, P. O. Box 2008, MS-6201, Oak Ridge, TN, 37831-6201, USA.
authors.forename: Sheng
authors.initials: S
authors.lastname: Dai
keywords: ZDDP; friction and wear reductions; ionic liquids; lubricant additives; synergistic effects