Professor of Chemistry
Professor of Material Science and Engineering
"Hundred Talents Program" Scholar of Chinese Academy of Sciences
B.S. Lanzhou University, China, 1990
M.S. Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 1997
Ph.D. Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 1999
Postdoctoral Fellow, University of California at Berkeley, 03.2000 – 08.2001
Postdoctoral Fellow, University of Alabama, 08.2001 – 02.2003
Postdoctoral Fellow, Rice University, 02.2003 – 07.2005
Nanostructure Thin Films and Nanolubrication
The physical, chemical and tribological properties of nanostructured diamond-like carbon films (DLC), organic thin films, functional gradient electroplatings,and nanomaterials, are investigated.
The research in our group is focused on understanding and controlling intrinsic nanostructure, surface and interfacial chemistry of thin films and applying this knowledge to a range of problems in MEMS, nanotechnology, space crafts, and automobile. The microstructure of thin films dominates their macro-properties, such as mechanical, tribological behaviors; furthermore, the role of interfaces becomes increasingly important as system dimensions are scaled downward. For instance, most electronic and optoelectronic devices are undergoing rapid scaling, with lengths moving into the nanometer range and the surface to volume ratio becoming very large. Therefore, the functions of many next generation devices, particularly, MEMS/NEMS, definitely depend critically upon the ability to design the intrinsic nanostructure of thin films applied onto devices components and to control and modify the properties of their interfaces.
Main thrust of our research is to devote a nanoscale-level understanding of the relation between of microstructure and macro/microscale mechanical and tribological performance of thin films so as to control the mechanical and tribological properties of the films through the design of the films with unique microstructures. Techniques used in the research include physical vapor deposition (PVD), chemical vapor deposition (CVD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM), transition electron microscopy (TEM), and various tribotesters.
Topics currently under study in the group include:
* Fullerene-like structure DLC films with superlubricity
* Noncrystal/nanocrystal network structure DLC films with low friction and long durability
* The electrochemistry deposition of DLC films in liquid phase
* The correlation between intrinsic structure and wettability/tribology of organic thin films
* Electroplating process of Cr(III) and alloy to replace Cr(VI) process
Junyan Zhang went to Lanzhou University in China, where he received a bachelor's degree in chemistry in 1990. Then he joined Lanzhou institute of Chemical Physics, Chinese Academy of Sciences, where he received a MS degree in 1997 in organic chemistry on the study of the fabrication, characterization and gas permeability of polyimide films, and received Ph.D. in 1999 in physical chemistry on the study of the tribochemistry mechanism of lubricating oil additives under boundary lubrication. He then went on to the University of California at Berkeley where he worked with David Bogy as a postdoctoral to study the degradation mechanism of PFPE lubes at the head-disk interface of hard disk drives. In 2001, he moved to the University of Alabama to study the nanomechanics and tribology of thin metal films with organic monolayer as interlayer and nanomaterials synthesis, worked with Shane Street as a postdoctoral. In 2003, he went to Rice University to continue his postdoctoral study on the protein crystal materials and nanomaterials with Vicki Colvin. In 2005, he was offered a titled professorship, Hundreds Talent Program, of chemistry and material science and engineering at Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences. His current research concerns the design and fabrication of nanostructure thin film including diamond-like carbon films and organic thin films et al. and nanolubrication.