Silica nanoparticles of 12 nm were surface-doped with ca. 350 (TTF-dppz)Yb(III) surface species, containing bis(propylthio)tetrathiafulvenyl[i]dipyrido-[3,2-a:2’,3-c]phenazine (TTF-dppz) as an antenna ligand through a Surface Organometallic Chemistry approach. These nanoparticles absorb and emit in the NIR (λabs = 750 nm, λem = 983 and 1050 nm) with a lifetime of 2.8 µs, similarly to the corresponding Yb(III) molecular complex (λabs = 750 nm, λem = 975, 986, 1009 and 1020 nm with τ1 = 6.93 µs). The silica materials were fully characterized using combined spectroscopic techniques (IR, NMR, UV-vis, luminescence and lifetime), molecular models and isostructural diamagnetic yttrium containing materials for easier characterization by NMR spectroscopy. Having established the surface structures and photophysical properties of these nanoparticles we transposed this methodology to larger silica particles with a diameter of ca. 100 nm. These larger nanoparticles have similar photophysical properties and contain ca. 30’000 chromophores, making possible one-photon NIR-to-NIR emission optical microscopy imaging of single nanoparticles.