In situ growth of CoPt nanoparticles in porous germania nanospheres

Mesoporous nanospheres of germania were used as matrix to grow CoPt nanoparticles. The host germania nanospheres were prepared by biomineralization via the recognition of the peptide sequence T-G-H-Q-S-P-G-A-Y-A-A-H. The size of the cobalt/platinum nanoparticles embedded in germania is in the 8–9 nm range, as determined by TEM analysis. The porosity of the nanocomposites was confirmed by nitrogen isotherm analysis. MFM analysis confirmed the magnetic properties of the germania nanocomposites. This simple method of preparation of germania nanospheres via biomineralization, followed by growth of CoPt nanoparticles has an attractive potential for preparing new optomagnetic materials. Such nanocomposites for various device fabrications can be produced and potentially be used to target specific applications.