Layered double hydroxide nanoparticles incorporating terbium: applicability as a fluorescent probe and morphology modifier

Stable and non-invasive fluorescent probes for nanotoxicological investigations are greatly needed to track the fate of nanoparticles in biological systems. The potential for terbium (Tb) to act as a fluorescent probe and its effect on layered double hydroxide (LDH) nanoparticle morphology are presented in this study. Incorporation of Tb during synthesis offers a simple methodology to easily tailor LDH nanoparticle thickness. A three-fold reduction in the average crystallite thickness (from 13 to 4 nm) has been achieved, whilst preferential lateral growth of LDH nanoparticles in the a-b crystal plane has been observed with increasing Tb loadings. Remarkably, Tb–LDH nanoparticles have emitted green fluorescence with a fluorescence quantum yield of 0.044.