Abstract: Devices, systems, and methods are provided that cause plasma-based chemical reactions. An example plasma-based reactor system includes a reactor chamber and an inlet port configured to provide an entry point for one or more reagents to enter the reactor chamber. The reactor system also includes an outlet port configured to provide an exit point for one or more chemical products to exit the reactor chamber. The reactor system also includes a resonator disposed within the reactor chamber and configured to provide a low-temperature coronal plasma when excited at a resonant wavelength. The low-temperature coronal plasma is configured to chemically modify at least a portion of the one or more reagents so as to form one or more chemical products.