One/two-photon sensitive sulfonium salt photoinitiators based on 1,3,5-triphenyl-2-pyrazoline

•Three novel 1,3,5-triphenyl-2-pyrazoline-based sulfonium salts were designed and synthesized as novel photoinitiators (PIs).•The newly synthesized PIs were highly sensitive to UV–Vis LEDs (365 nm–425 nm)•The quantum yields of photoacid generation of PIs are high and wavelength-dependent.•The pyrazoline-based PIs can initiate cationic polymerization as well as free radical polymerization.•The PIs can be applied in two-photon induced lithography.