Electrochemistry on Nano- and Atomic Levels: Scanning Probe Microscopy Meets Deep Data
Structural and electronic properties of oxide surfaces control their physical functionalities and electrocatalytic activity, and are currently of interest for energy generation and storage applications. In this presentation, I will discuss several examples of high-resolution studies of the electronic and electrochemical properties of oxide surfaces enabled by multidimensional scanning probe microscopies. On the mesoscopic scale, combination of strain- and current sensitive scanning probe microscopies allows to build nanometer-scale maps of local reversible and irreversible electrochemical activities. The use of multivariate statistical methods allows separating the complex multidimensional data sets into statistically significant components which in certain cases can be mapped onto individual physical mechanisms. I will further discuss the use of in-situ Pulsed Laser Deposition growth combined with atomic resolution Scanning Tunneling Microscopy and Spectroscopy to explore surface structures and electrochemical reactivity of oxides on the atomic scale. For SrRuO3, we directly observe multiple surface reconstructions and link these to the metal-insulator transitions as ascertained by UPS methods. On LaxCa1-xMnO3, we demonstrate strong termination dependence of electronic properties and presence of disordered oxygen ad-atoms. The growth dynamics and surface terminations of these films are discussed, along with single-atom electrochemistry experiments performed by STM. I further explore the opportunities for atomically-resolved imaging and property data mining of functional oxides extending beyond classical order parameter descriptions, and giving rise to the deep data analysis in materials research. Finally, I will briefly discuss recent results on using electron microscopy as a way to control and probe local electrochemical functionality in oxides and other materials, and discuss further opportunities for nanoelectrochemistry and nanotechnology in general.
This research is supported by the by the U.S. Department of Energy, Basic Energy Sciences, Materials Sciences and Engineering Division, and was conducted at the Center for Nanophase Materials Sciences, which is sponsored at Oak Ridge National Laboratory by the Scientific User Facilities Division, BES DOE.
Sergei V. Kalinin is the director of the ORNL Institute for Functional Imaging of Materials and distinguished research staff member at the Center for Nanophase Materials Sciences (CNMS) at Oak Ridge National Laboratory (at ORNL since 2002). He also holds a Joint Associate Professor position at the Department of Materials Science and Engineering at the University of Tennessee-Knoxville, and an Adjunct Faculty position at Pennsylvania State University. His research interests include application of big data, deep data, and smart data approaches in atomically resolved and mesoscopic imaging to guide the development of advanced materials for energy and information technologies, as well as electromechanical, electrical, and transport phenomena and matter patterning on the nanoscale via scanning probe and electron microscopy.
He received his Ph.D. from the University of Pennsylvania in 2002, followed by a Wigner fellowship at ORNL (2002-2004). He is a recipient of the RMS medal for Scanning Probe Microscopy (2015); Presidential Early Career Award for Scientists and Engineers (PECASE) (2009); IEEE-UFFC Ferroelectrics Young Investigator Award (2010); Burton medal of Microscopy Society of America (2010); ISIF Young Investigator Award (2009); American Vacuum Society Peter Mark Memorial Award (2008); 3 R&D100 Awards (2008, 2010, and 2016); Ross Coffin Award (2003); Robert L. Coble Award of American Ceramics Society (2009); and a number of other distinctions. He has published more than 500 peer-reviewed journal papers, edited 3 books, and holds more than 10 patents. He has organized numerous symposia (including symposia on Scanning Probe Microscopy on Materials Research Society Fall meeting in 2004, 2007, and 2009) and workshops (including International workshop series on PFM and Nanoferroelectrics), and acted as consultant for companies such as Intel and several Scanning Probe Microscopy manufacturers. He is also a member of editorial boards for several international journals, including Nanotechnology, Journal of Applied Physics/Applied Physics Letters, and recently established Nature Partner Journal Computational Materials.