Optical limiting performance of meso-tetraferrocenyl porphyrin and its metal derivatives

meso-Tetraferrocenyl porphyrin and its metal derivatives were found to be excellent optical limiters towards second harmonic of Q-switched Nd:YAG nanosecond laser. meso-Tetraferrocenyl porphyrin 3a, its zinc 3b, and copper 3c derivatives exhibited superior optical limiting performance than the benchmark fullerene C60, and rest of the metal derivatives 3d–3e are comparable. Reverse saturable absorption phenomena is mainly responsible for the optical limiting behaviour in these compounds. The ratio σex/σ0 was estimated from the nonlinear transmission characteristics of 3a–3e. The ratio σex/σ0 more than 7 was obtained in case of 3a, which makes them attractive candidates as optical limiting material.