Two-photon absorbing performance and interfacial coordination enhanced mechanism of TPPA-CdS hybrid

Abstract

A novel organic/inorganic hybrid which consisted of N,N-diphenyl-4-(2,2':6′,2″-tepyridin-4-yl)aniline (abbreviated as TPPA) and CdS nanoparticles (NPs) had been prepared through interfacial coordination effect according to soft-hard-acid-base principle. The interfacial coupling coordination was analyzed by XRD, far-IR, FT-IR and HRTEM, which resulted in changeable morphology and tunable linear/nonlinear optical properties. Upon interfacial coordination, the hybrid showed a red-shifted (55 nm) UV–vis absorption band, weakened single photon fluorescence emission (84% decrease), and enhanced two-photon absorption cross-section (13 folds). Due to excellent two-photon absorbing character, the hybrid had good application in the field of optical power limiting with 43 W⋅cm−2 limiting threshold. The regulation mechanism of optical properties was thoroughly discussed upon single crystal structure of the interfacial coordination complex and quantum calculation, as well as the growing mechanism of the hybrid.