We describe the synthesis of Gd(III)-doped carbon dots as dual fluorescence-MRI probes for biomedical applications. The derived Gd(III)-doped carbon dots show uniform particle size (3–4 nm) and gadolinium distribution and form stable dispersions in water. More importantly, they exhibit bright fluorescence, strong T1-weighted MRI contrast and low cytotoxicity.

Transparent, flexible and luminescent hybrid films composed of 2D-ordered nitrogen-doped carbon nanodots and clays are synthesized via top-down and bottom-up approaches.