Hot Plate Photoreactor

Gihyun Lee is researching the synthesis and chemical properties of photo-switchable metal–organic frameworks (MOFs) using organic ligands that reversibly switch between trans and cis forms under light irradiation. MOF solvothermal synthesis requires stirring reaction mixtures at elevated temperatures with illumination at specific, high intensity wavelengths.  In collaboration with the Amy Facility, a custom illumination source has been developed to meet her specific research needs.

The primary features requested were an illumination source which was easily movable from one reaction pot to another, self-contained, confined photons to the reactor, and easily adjustable intensity. 

These goals were met by designing a chamber that fits precisely over the heated reaction vessel (beaker on a stirring hotplate) and coating the interior with a reflective film. The chamber has slots towards the bottom to allow for airflow, and it has a hole in the top allowing a thermometer / thermocouple to be inserted into the reaction vessel for temperature monitoring and closed loop temperature control. Wavelengths are adjustable by replacing the high intensity LED as needed.

The top of the reactor is modular and can be attached to chambers of various sizes. It contains the LED, a heatsink, a cooling fan, and all of the control electronics on a custom designed PCB. The controller allows the scientist to select from 3 different power levels on the LED, and it also allows for the fan speed to be adjusted. The cooling fan not only cools the LED by pulling air over the heatsink, but it helps maintain chamber temperature by pulling air through the reaction chamber and helps cool the control electronics by exhausting air over the primary control FETs.