Designing poly(arylene ether sulfone)s with platinum(II) acetylide to regulate photophysical properties towards solid-state nonlinear limiter

We present two types of poly(arylene ether sulfone)s (PAES) derived from platinum acetylide, featuring varying conjugation lengths and platinum-contents. The platinum-incorporated PAES exhibit outstanding thermal properties (Tg > 180℃, Td5% ≥ 400℃) with easily processing into solid films from solvents.

Photophysics, ultrafast transient absorption (TA), Z-scan characterizations and theoretical calculations reveal an abnormal intersystem crossing (ISC) and the principle of triplet nonlinear limiting (S0→S1→Tx→T1→Tn). The extended τP caused by the longer conjugated ligand is more critical on NLA, compared with the lower ΦP caused by higher Pt-contents. PAES with longer conjugated ligand exhibit superior intrinsic NLA under limited platinum content, while those with shorter conjugated ligands strike a balance between transparency and NLA.