Tengfei Cao earned his Ph.D. in Interdisciplinary Materials Science in April 2021 under the direction of Dr. Sharon Weiss. Tengfei investigated the use of nanoscale porous silicon-based label-free optical biosensors towards point-of-care diagnostics applications, with the goal of overcoming challenges that often prevent benchtop lab instruments from being adapted to simple biosensors that can be operated in a straightforward manner outside the laboratory. In one key advance, he demonstrated the feasibility of using a smartphone to quantitatively measure the color change introduced when molecules are selectively captured by a porous silicon biosensor. Tengfei is now a Product Development Engineer at KLA in Milpitas, CA.