Microwave-enhanced Emission Intensity and Plasma Lifetime in Laser-induced Breakdown Spectroscopy

摘要

A new microwave (MW)-enhanced laser- or spark-induced breakdown spectroscopy (LIBS or SIBS) instrument for atomic and molecular spectra was developed. Plasma was initially generated by laser- or spark-induced breakdown and then sustained only by MWs. The plasma lifetime was easily controlled by the MW input power and duration, which afforded steady accumulation of LIBS and SIBS spectra. Therefore, the spectral peak intensity was enhanced dramatically. For example, the peak intensity of the LIBS Pb spectra increased by 15 times and that of SIBS increased by 880 times. In addition, the MW-enhanced spark-induced system has the potential to replace the laser in LIBS with spark discharge as a readily available, compact plasma source.