Indian American researcher Gurpreet Singh, an assistant professor of mechanical and nuclear engineering at Kansas State University, has received a $500,000 National Science Foundation Career award for his research on nanosheets.
Singh has done research on “Scalable liquid exfoliation processing of ultra-thin two-dimensional metal dichalcogenides nanosheets for energy storage devices” and he intends to use the award money to develop ultrathin metal sheets, which can help produce better rechargeable batteries, supercapacitors and catalysts for photoelectrochemical hydrogen production.
“Most negative electrodes for sodium-ion batteries use materials that undergo an ‘alloying’ reaction with sodium,” Singh said. “These materials can swell as much as 400 to 500 percent as the battery is charged and discharged, which may result in mechanical damage and loss of electrical contact with the current collector.”
“Molybdenum disulfide, the major constituent of the paper electrode… offers stable charge capacity of 230 mAh.g-1, with respect to total electrode weight… This design also eliminates the polymeric binders and copper current collector foil used in a traditional battery electrode.”
The research appeared in the journal ACS Nanoin.
With his Career award, Singh will study large-scale production of ultrathin sheets – a few atoms thick and several micrometers wide – of transition metal dichalcogenides, or TMDs. Nearly 40 types of TMDs have been identified, including naturally occurring molybdenite.
For the latest research, the engineers created a large-area composite paper that consisted of acid-treated layered molybdenum disulfide and chemically modified graphene in an interleaved structured.
The research marks the first time that such a flexible paper electrode was used in a sodium-ion battery as an anode that operates at room temperature. Most commercial sodium-sulfur batteries operate close to 300 degrees Celsius, Singh said.
Gurpreet Singh’s other research has focused on using graphene oxide to improve sodium- and lithium-ion flexible batteries and creating carbon nanotubes for better laser detectors and rechargeable batteries.
The researchers are working to commercialize the technology, with assistance from the university’s Institute of Commercialization. They also are exploring lithium and sodium storage in other nanomaterials.