Xi Chen

2016 Regional Award Finalist — Post-Doc

Xi Chen

Current Position:
Assistant Professor

Columbia University (now at CUNY Advanced Science Research Center and The City College of New York)

Materials Science & Nanotechnology

Recognized for: Pioneering work on energy harvesting using water-responsive biomimetic materials to create evaporation-driven engines and generators

Areas of Research Interest and Expertise:  Bio-inspired Materials, energy harvesting, nanomechanics, biophysics, atomic force microscopy


PhD, Mechanical Engineering, Stevens Institute of Technology
MS, Precision Instruments, Tsinghua University, China
BS, Mechanical Engineering, Tsinghua University, China

Evaporation contains a huge amount of invisible power which drives rain, wind, and waves. In biological world, many plants obtain energy from evaporation to power their vital tasks. For example, trees use evaporation to lift water from the soil to their leaves, and pine cones use evaporation to release their seeds. Can humans use evaporation to power a car, or perhaps an entire city?

As a postdoctoral fellow at Columbia University, Dr. Xi Chen worked with Dr. Ozgur Sahin to reveal the possibility to directly harvest energy from evaporation. Dr. Chen found that the energy density of Bacillus spores, which can swell and shrink in response to humidity, is significantly higher than all other actuator materials. Using spores, Dr. Chen developed two engines that can directly convert energy of evaporation into mechanical motion and electricity. These engines continuously generate power when installed above a natural or manmade body of water. The power density of these engines is potentially comparable to that of modern solar and wind power plants, but at a significantly lower cost. These systems can also store and deliver power on demand, and conserve water by reducing evaporative losses.

“I will continue studying and developing water-responsive materials and evaporation energy harvesting. Hopefully, our technique of evaporation energy harvesting can help us to address energy and water challenges the world is facing today.”

Key Publications: 

  1. Xi Chen, Davis Goodnight, Zhenghan Gao, Ahmet-Hamdi Cavusoglu, Nina Sabharwal, Michael Delay, Adam Driks, Ozgur Sahin. Scaling up nanoscale water-driven energy conversion into evaporation-driven engines and generators. Nature Communications. 2015
  2. Xi Chen, L Mahadevan, Adam Driks, Ozgur Sahin. Bacillus spores as building blocks for stimuli-responsive materials and nanogenerators. Nature Nanotechnology. 2014
  3. Xi Chen, Jinwei Li, Guitao Zhang, Yong Shi.  PZT nano active fiber composites for acoustic emission detection. Advanced Materials. 2011
  4. Xi Chen, Shiyou Xu, Nan Yao, Yong Shi. 1.6 Volt nanogenerator for mechanical energy harvesting using PZT nanofibers. Nano Letters. 2010

Other Honors:

2015       Postdoctoral Research Symposium Award, Columbia University
2012       James Harry Potter Award, Stevens Institute of Technology

In the Media:

Evaporation Gives Spores Energy-Generating Muscle. The New York Times. June 29, 2015
The Energizer Bacterium. The Wall Street Journal. February 7, 2014