Liu's primary interests lie in fundamental understanding of the effect of structure, defects, and microstructure on transport and electrical properties of surfaces and interfaces. In particular, he is interested in developing new materials for energy storage and conversion, for chemical sensing, and for hydrogen production and separation In addition, he is interested in mathematical modeling of mass and charge transport in solid electrochemical systems and polarization at interfaces.

Liu's current research activities include (1) in-situ characterization of gas-solid interactions using FTIR/Raman spectromicroscopy, impedance spectroscopy, and mass spectrometry; (2) study of transport phenomena and kinetics in ionic and electronic conductors and the effect of imperfections on electrophysical and electrochemical properties; (3) fabrication and characterization of ceramic membranes, thin films, and coatings; mesoporous and nanostructured electrodes and interfaces; and solid-state ionic devices; and (4) development of new materials for high-selectivity gas sensors, for high-energy-density batteries, for low-temperature solid-state fuel cells, and for high temperature PEM fuel cells.

Liu holds 20 U.S. patents and a number of patent applications, co-edited seven proceedings volumes, and published more than 250 papers in reputed journals, book chapter, and conference proceedings. He has also been the co-organizer of 11 international symposia/workshops on materials for energy storage and conversion devices, sensors, and gas separation.

Liu is a fellow of the American Ceramic Society (ACerS) and the Electrochemical Society (ECS). He is the recipient of a Ross Coffin Purdy Award (American Ceramic Society, 2010), an NASA Tech Brief Award (2007), an invited participant, US-Japan Frontiers of Engineering (National Academy of Engineering, 2007); a Crystal Flame Innovation Award in Research (FuelCell South, 2005); an Outstanding Achievement in Research Program Development Award (Georgia Tech, 2003), A Sustained Research Award (Sigma Xi, 2003), a senior Teaching Fellow (Georgia Tech, 2002), a Best Faculty Paper Award (Sigma Xi, 2001), an Outstanding Faculty Research Author Award (Georgia Tech, 1999), an invited participant, Frontiers of Engineering (National Academy of Engineering, 1997), a Best MS Thesis Advisor Award (Sigma Xi, 1996), a National Young Investigator Award (NSF, 1993-98), and a Scholastic Achievement Award (Golden Gate Chapter of ASM, 1986).

Valeria Tohver Milam joined the School of Materials Science and Engineering at Georgia Institute of Technology as an assistant professor in July 2004. She received her B.S. in Materials Science and Engineering with Honors from the University of Florida in 1993. After completing her M.S. degree (1997) in MSE at the University of Illinois, Urbana-Champaign, she interned at Sandia National Laboratories. She then completed her doctoral work at UIUC studying the phase behavior, structure and properties of nanoparticle-microsphere suspensions. Experimental results suggested a novel colloidal stabilization mechanism known as nanoparticle “haloing” in which otherwise negligibly charged microspheres become effectively charge-stabilized by their surrounding shell of highly charged nanoparticles.

After finishing her Ph.D. in 2001, her postdoctoral studies at the University of Pennsylvania focused on DNA-mediated colloidal assembly. The degree of specific attraction between DNA-grafted microspheres was found to vary with sequence length, sequence concentration and ionic strength. A variety of structures such as colloidal chains, rings and satellites were formed by varying the particle size ratio and suspension composition.