The method of determining the accessibility, nature and location of functional sites within the mesoporous materials was presented. The nanoparticles were characterized using a combination of high-resolution scanning transmission electron microscopy, infrared spectroscopy and elemental analysis. The use of mixed-metal Ru6Sn clusters showed the high accessibility to the mesoporous channels in nanosized silica particles.
Hermans, S., Sadasivan, S., Judkins, C. M. G., Johnson, B. F. G., Mann, S., & Khushalani, D. (2003). Probing of Functionalized Mesoporous Silica Nanoparticles Using Transition Metal Clusters. Advanced Materials, 15(21), 1853-1857. https://doi.org/10.1002/adma.200305350 (Original work published 2003)