Fig. 1.

a TEM image of the MSNs–CDs nanohybrid (inset: high-resolution image and size distribution of MSNs–CDs). b Hydrodynamic diameter distributions, c zeta potentials, d small-angle XRD patterns, e N₂ adsorption–desorption isotherms, f pore size distribution curves, g FT-IR spectra, and h TGA curves of MSNs, MSNs–NH₂, and MSNs–CDs. i High-resolution C 1s XPS spectrum of the MSNs–CDs nanohybrid and fittings