AUTHOR=Rohlmann Patrick , Munavirov Bulat , Furó István , Antzutkin Oleg , Rutland Mark William , Glavatskih Sergei TITLE=Non-halogenated Ionic Liquid Dramatically Enhances Tribological Performance of Biodegradable Oils JOURNAL=Frontiers in Chemistry VOLUME=Volume 7 - 2019 YEAR=2019 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2019.00098 DOI=10.3389/fchem.2019.00098 ISSN=2296-2646 ABSTRACT=Ionic liquids open the possibility of tribotronic control – the ability to select either the anion or cation at the surface and tune the corresponding interfacial film structure and thus the friction of the system. Conventional, halogenated ionic liquids are unsuitable for such applications due to toxicity of the species produced during tribochemical reactions. Similarly, there is increasing pressure to replace conventional lubricant oils with biodegradable ones for reasons of sustainablility. We show that a phosphonium orthoborate ionic liquid, if added to biodegradable oils, reduces the wear of steel surfaces by up to 92% compared to the neat oils at 90C. It is shown that the ionic liquid is preferentially adsorbed and, that the reduction in wear can be traced to the formation of complex boron enriched patches of boundary films during shear.