This lecture will give the historical introduction into the field of synchrotron radiation based Photoionization-MS, address synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) combined with the molecular-beam sampling technique and its applications. SVUV-PIMS has been demonstrated to be a powerful and versatile diagnostic tool due to its broad tunability, high energy resolution, and minimal fragmentation interference. SVUV-PIMS has achieved significant success in energy conversion research—including combustion, biofuel production, and catalytic reactions etc.—by enabling highly sensitive detection of reactive intermediates and identification of isomers. These diagnostic capabilities have substantially advanced the development of high-fidelity reaction models, contributing not only to fundamental studies in energy conversion but also to practical applications critical to the realization of green energy and carbon neutrality goals.
