Polychromatic excitation improves detection limits in total reflection X-ray fluorescence analysis compared with monochromatic excitation

Detection limits obtained by a portable total reflection X-ray fluorescence (TXRF) spectrometer with or without a monochromator are compared. A 1WX-ray tube (tube voltage: 20 kV) is used in this spectrometer. Polychromatic excitation improves the detection limits in TXRF analysis with the low power X-ray tube compared with monochromatic excitation. A detection limit of 26 pg is achieved for Co when using the weak polychromatic X-rays.