Audrey ChengAudrey Cheng loves chemistry. It’s a love the 17-year-old Californian says she did not inherit from her parents, both of whom are computer engineers. “Dad always declares, ‘Chemistry is a foreign language to us,’” says Audrey. “‘We don’t have that in our DNA.’”

Maybe not, but last week, Audrey’s project improving the energy output of organic solar cells earned her a spot as one of 300 semifinalists in the 2016 Intel Science Talent Search (STS), one of the most prestigious science and math competitions for high school seniors in the United States. It also made her one of the 80 semifinalists who are also CTYers. 

Audrey says her interest in chemistry started with a single course she took the summer before eighth grade, when, after hearing about CTY from a friend, she enrolled in a summer program at Loyola Marymount University. The high point, she says, was the last lab, when she got to make aspirin: “That was exciting for me—I was synthesizing a compound, I was actually making something. It showed me that chemistry has a lot of potential to help others.”

Two years ago, Audrey decided to hone that potential. She applied for and won a 2014 CTY Cogito Research Award, a program that provides 10 winning students (or student teams) with small grants and virtual mentors to help each of them complete a proposed STEM research project. Working with help from John Tovar, an organic chemist at Hopkins, Audrey found a new way to attach biological molecules called peptides to carbon nanotubes—literally one-atom-thick sheets of carbon rolled into tiny pipes—so that these tubes could then be used to transport drugs to specific parts of the body. “That was my first experience doing research,” she says.  “It jump-started my journey.”

 As a Garcia Research Scholar at Stony Brook University last summer, Audrey began working with organic solar cells. These solar cells take light from the sun and turn it into electricity.  Sounds great, but the problem is efficiency, meaning they don’t produce much electricity relative to the sunlight they take in.

Audrey wanted to help change that. Working summer weekdays until late afternoon and then several more hours on weekends, she experimented with adding to the solar cell a second electron donor, which she expected to increase the range of light over which the cell could generate more electricity. Her first attempt led to her worst day in the lab: “I think it was a Friday. We were using Excel to calculate the efficiencies… and they were lower than the controls! My project had actually decreased efficiency,” she remembers. “It was kind of depressing because there were other kids in the program and their results were pretty good, but I knew that research is mostly failure, right? And I knew I had more time.”

Reading up on other nanomaterials that she could use, Audrey landed on the idea of adding graphene to the solar cells, specifically to the nanocolumns inside them.  “The graphene sticks to the sides of the columns and creates more surface area for the donors and acceptors to be in contact, and that contact is what generates electricity,” she explains. The result? A 95 percent increase in efficiency!

When Audrey entered her project in the Intel STS, she never expected to make it to the semifinals.  “I totally didn’t think this would happen,” she says. As a semifinalist, she will receive a $1,000 award, and another $1,000 will go to her school, Henry M. Gunn High School in Palo Alto. On January 20, 40 of the 300 semifinalists will be named Intel Science Talent Search finalists, who will travel to Washington, D.C., in March to compete for the top awards.

When she’s not working on her science projects or going to school, Audrey likes to play Lacrosse, hang out with friends, and spend time with her three birds: two parakeets and a quail, who “actually all get along pretty well.” And she’s been busy with college applications. She doesn’t yet know what school she will attend, but she knows she wants to be in the lab. “I like seeing things happen with my own eyes,” she says. “That’s what gets me excited.” — Kristi Birch