Using infrared heat transfer to modify chemical reactions

Using an optical cavity to confine infrared light waves, researchers focused on the thermal dehydration of an inorganic crystal, copper sulfate pentahydrate. They found that light-matter vibrational coupling (resulting in states known as polaritons) lowered the temperature needed for dehydration by up to 14 degrees Celsius. This was attributed to radiative energy transport, in which heat energy is radiated outward as photons from a hot region are absorbed by a cooler region (the crystal) -- a mechanism of heat conduction that had been overlooked until now.

This work establishes a mechanism for modifying thermochemical processes using optical cavities, with implications for the development of catalytic systems that exploit these interactions to achieve targeted control over certain chemical reactions and optoelectronic processes.

This study was published January 16, 2025 in Nature Chemistry. The research team includes Sindhana Pannir-Sivajothi, Yong Rui Poh & Joel Yuen-Zhou (all UC San Diego); Zachary Brawley (Texas A&M); and Matthew Sheldon and Ju Eun Yim (both UC Irvine).

Their research was funded by the National Science Foundation (CHE-2108288), the Welch Foundation (A-1886), the W.M. Keck Foundation, and the American Chemical Society Petroleum Research Fund (ACS PRF 60968-ND6).