HERFD operates by selectively measuring the fluorescence emitted by a sample upon X-ray excitation. A crystal analyzer is used to focus on a narrow energy range of the emitted fluorescence, filtering out unwanted background noise and increasing the resolution. This process involves:
Exciting the sample with a monochromatic X-ray beam. Detecting the emitted fluorescence using a crystal analyzer tuned to a specific energy. Recording the intensity of the fluorescence as a function of the incident X-ray energy.
By focusing on specific fluorescence lines, HERFD can provide a high-resolution view of the electronic structure, even in complex and heterogeneous catalytic systems.
