Award boosts development of solar cells with atomically thin semiconductors

Chemistry professor Jiwoong Park has won a $120,000 award over two years from the Camille and Henry Dreyfus Foundation to support a postdoctoral fellow who will help develop advanced photovoltaic materials at the University’s Institute for Molecular Engineering and Department of Chemistry. Park selected Yu Zhong, who just finished his doctorate in chemistry at Columbia University, for the fellowship.

Solar energy is one of the most promising ways to replace fossil fuels, thereby reducing pollution and minimizing climate change, Park said. “This award will be used to develop new materials and architecture for high-performance hybrid solar cells in the form of economical, detachable, lightweight photovoltaic films.”

The materials will utilize semiconductors that are only one atom thick and will therefore be especially suited for photovoltaic materials that will power nanomachines, such as sensors and detectors.

“When miniaturizing machines, a current limitation is the size of the power source,” Park said. “The thin photovoltaic materials that we will develop will be foldable, like an umbrella. They will be very small when folded but larger when open.”

Such nanomachines would have many applications, he added. “For example, imagine sending thousands of them into the air to gather data about crops or the weather.”

To achieve this, the researchers will synthesize, functionalize and stack atomically thin semiconductors called transition-metal dichalcogenides (TMD), along with other components, into photovoltaic material. The new material will have unique mechanical and electrical characteristics that broaden the application of solar cells and improve their performance, the researchers say.

Their work will combine two active and competitive fields of research: inorganic TMDs, for which Park is renowned, and organic photovoltaics. The former provides a flexible matrix and the latter provides a method for doping the material, which refers to the deliberate, controlled introduction of impurities to semiconductors as a way to alter their mechanical and electrical properties.

“While the layers of TMDs will provide a solid-state material that acts like a platform with advanced physical properties, the organic photovoltaic molecules will provide additional functionalities and allow for direct tuning of the hybrid material’s doping and magnetic fields,” Park said.

“These detachable solar cells will chart a new path to economical, reusable photovoltaic devices for renewable energy sources,” he added.

“There is a great untapped potential in bridging TMDs enhanced with organic photovoltaic materials,” Zhong said. “In order to make hybrid solar cells from these materials, we need to chemically functionalize the materials. My background in organic chemistry and solar cells made me suitable for this work.”

Zhong will be the first fellow in Park’s group of four postdoctoral scholars and six graduate students, all of whom have moved from Cornell University to the University of Chicago.

“There are many opportunities and possibilities in the overlapping realm of inorganic TMDs and organic materials, and the University of Chicago, with its interdisciplinary environment, is a great place to explore these ideas,” Zhong concluded.

The Camille and Henry Dreyfus Foundation is a nonprofit organization devoted to the advancement of chemical sciences. This is the University’s seventh Dreyfus postdoctoral fellowship.