BS in Materials Engineering
Materials Engineering Department
A PDMS microfluidic reactor was made in Cal Poly’s class 1000 clean room for the purpose of synthesizing quantum dots. The device master mold was made from a silicon substrate and SU-8 features 50μm tall. The PDMS reactor was cast from that mold. The flow rates of fluid through the channels, heating of the reactor and pressure in the reactor were measured in order to characterize the potential for synthesizing quantum dots. Flow rates of 20 mL/hr through 4 mL/hr were tested to characterize the consistency of amount of time the fluid remains in the reactor at a constant flow rate. At 20 mL/hr the reactor has an average reaction time of 30.2±4.1 seconds, and 93.9±4.1 seconds for the 5 mL/hr flow rates. The reactor needs to be able to run at 185 ⁰C in order for the chemical reaction of growing quantum dots to occur. The heating apparatus can reach the desired 185⁰C temperature and maintain it within 10⁰C while fluid is running through it. The maximum operating pressure of the reactor is 200 kPa. When running octadecene, the organic solvent used in quantum dots synthesis, at 185 ⁰C the pressure inside the reactor is 195.6 kPa. This results in a high failure rate of reactors when running a quantum dot synthesis. However the PDMS reactor has all the needed properties to synthesis quantum dots.