As a high school student I always liked physics, math and chemistry, and in China if you’re good at those things, the natural path is to enter engineering. I was assigned to a major in thermal engineering, which is all about power generation. I knew nothing about it, but I learned about power plants, how airplanes fly, and how energy transformation – such as from solar energy to electricity – can occur. It was something I learned to love, rather than loved and chose.
When I came to the U.S. for graduate school, I didn’t have any specific career goals; I just wanted to learn new things, and I focused on combustion problems – engines, how fuel burns, the chemistry that happens when that burning takes place. In my fifth year of graduate school, my advisor, Prof. C.K. Law at Princeton University, encouraged me to pursue academia. I wasn’t sure this was what I wanted to do, but I followed his guidance. When the opportunity came to work at Stanford, it was too good to pass up, and I took it. I didn’t know if I’d be successful; I hadn’t prepared for it, and I’d also changed my research topic. My work until then had been in combustion, but renewable energy was booming at that point. Making the switch was very frightening; I was unsure about my future, but I really wanted to see what I could do, so I went ahead.
Today, my research group looks at how combustion, nanomaterials and energy conversion can work together to create valuable chemicals that are useful in applications like fuel cell cars, in the storage of renewable energy, and in the creation of disinfectants such as hydrogen peroxide. I love the creativity of finding connections between different disciplines; that’s where I’ve had my best ideas. One area we’re working on involves green hydrogen. A major goal for the U.S. is to achieve net-zero carbon by 2050, and hydrogen will play an important role in that, but the process we use now to produce hydrogen generates about 2-3% of global CO2. We want to find a way to generate it cheaply without the carbon footprint. Green hydrogen could be used in several major applications, like making ammonium for fertilizer and refining petroleum, and could also help decarbonize industries that have a heavy carbon footprint, like cement and steel production.
I tell students thinking about engineering that they’re more capable than they think they are. You can do more than you’ve imagined, and your abilities can be stretched and cultivated by facing different challenges. Engineers are the nuts and bolts of society; we do the work to make society function, and because of that, we have a real impact on the world.