@article{seed_acharya_perelygin_smirnov_krim_2021, title={Tribotronic control and cyclic voltammetry of platinum interfaces with metal oxide nanofluids}, volume={566}, ISSN={["1873-5584"]}, DOI={10.1016/j.apsusc.2021.150675}, abstractNote={Nanotribological and electrochemical behavior of platinum-nanofluid interfaces are reported for aqueous suspensions of positively charged Al2O3 and negatively charged TiO2 nanoparticles, employing Quartz Crystal Microbalance (QCM) and cyclic voltammetry (CV) techniques. Tribotronic methods were employed to adjust the nanoparticles’ positions relative to Pt surface electrodes, and both voltammetry and tribological performance measures were observed to be highly sensitive to the adjustments. Interfacial friction levels were observed to be higher for both types of nanoparticles when electrostatically driven towards the surface. For electric fields of sufficient amplitude and duration, the TiO2 nanosuspension exhibited properties consistent with reversible electrophoretic deposition of the nanoparticles, accompanied by changes in the electrochemical attributes of the electrode itself. Overall, the study suggests a method for active tribological control and optimization of device performance in applications where suspensions of charged nanoparticles are present and can be exposed to external fields.}, journal={APPLIED SURFACE SCIENCE}, author={Seed, C. M. and Acharya, B. and Perelygin, V and Smirnov, A. and Krim, J.}, year={2021}, month={Nov} }
 @article{perelygin_voinov_marek_ou_krim_brenner_smirnova_smirnov_2019, title={Dielectric and Electrostatic Properties of the Silica Nanoparticle-Water Interface by EPR of pH-Sensitive Spin Probes}, volume={123}, ISSN={["1932-7455"]}, url={https://doi.org/10.1021/acs.jpcc.9b08007}, DOI={10.1021/acs.jpcc.9b08007}, abstractNote={Interfacial electrostatic properties of monodisperse silica nanoparticles (SiNPs) in aqueous suspensions as a function of bulk pH were characterized by spin labeling EPR of two ionizable nitroxides: (1) IMTSL (S-(1-oxyl-2,2,3,5,5-pentamethylimidazolidin-4-yl)methyl methanesulfo-nothioate) and IKMTSL (S-4-(4-(dimethylamino)-2-ethyl-5,5-dimethyl-1-oxyl-2,5-dihydro-1H-imidazol-2-yl). SiNPs of ca. 116 nm in diameter (by particle number) were synthesized using the Stober method and their surface was modified by silanization under harsh conditions to ensure robust attachment of the thiol-terminated ligands to the silica surface. These ligands were consequently modified with either IMTSL or IKMTSL to characterize the surface electrostatic potential of the nanoparticles from their EPR spectra. EPR titration data for these two pH-sensitive nitroxides allowed for differentiating the dielectric and electrostatic contributions to the interfacial properties of SiNPs. From such a titration at room temperature an effect...}, number={49}, journal={JOURNAL OF PHYSICAL CHEMISTRY C}, publisher={American Chemical Society (ACS)}, author={Perelygin, Vladislav and Voinov, Maxim A. and Marek, Antonin and Ou, Erkang and Krim, Jacqueline and Brenner, Donald and Smirnova, Tatyana I and Smirnov, Alex I}, year={2019}, month={Dec}, pages={29972–29985} }