Materials Science and Engineering Graduate Seminar

March 27, 2018
March 27, 2018
Speaker: Xi Chen, Ph.D.
                 Columbia University  
Title: Capture Carbon Dioxide from Ambient Air
Time: Noon
Abstract: Confinement on nanoscale is essential in determining the dynamics and energetics of many physical and chemical systems. Atoms are forced into contact with the confined layer, which lead to different behaviors than in the bulk. Here we report a first discovered unconventional reverse chemical reaction driven by water quantities in nanopores. In a system containing nanoporous materials and carbonate ions, CO2 capture from ambient air can be fulfilled by controlling the relative humidity. The system absorbs CO2 from the air when the surrounding is dry, whereas desorbs CO2 when wet. A design of such a CO2 absorption/desorption system is investigated using molecular dynamics and quantum mechanics simulations, further validated using experiments. Its working mechanism is revealed as the reduction of free energy of the carbonate ion hydrolysis with the decrease of the number of water molecules in confined nanopores. The influences of pore size, surface hydrophobicity, temperature, and spacing of cations on CO2 capture efficiency are elucidated. The study not only helps to design an effective direct CO2 air capture system, but also more broadly opens a new door on inspiring energy efficient absorbent for quite a few species.
Bio: Dr. Xi Chen is currently a Professor in the Department of Earth and Environmental Engineering at Columbia University. He received his B.S. in Engineering Mechanics from Xi'an Jiaotong University in 1994 (at the age of 18), M.S. in Solid Mechanics from Tsinghua University in 1997, and Ph.D. in Solid Mechanics from Harvard University in 2001. He was a postdoctoral fellow at Harvard University from 2001-2003. He joined Columbia University in 2003. He uses multiscale theoretical, experimental, and numerical approaches to investigate various research frontiers in materials addressing challenges in energy and environment, nanomechanics, and mechanobiology. He has published over 300 journal papers with a h-index over 50. He received the NSF CAREER Award in 2007, the Presidential Early Career Award for Scientists and Engineers (PECASE) in 2008, ASME Sia Nemat-Nasser Early Career Award in 2010, SES Young Investigator Medal in 2011, ASME Thomas J. R. Hughes Young Investigator Award in 2012, and a number of international recognitions from Japan, Korea and China. He is a Fellow of ASME and chaired its Materials Division in 2017.
Hosted by: Professor Richard Lehman

For more information, please contact Sheela Sekhar at or 848.445.2159.