SnO
2
nanoparticles have been prepared by the sol–gel method using SnCl
4
as a precursor and
subsequent heat-treatment at 600
1
C. The structural and chemical properties were investigated using
x-ray diffraction, scanning electron microscopy, and x-ray photoelectron spectroscopy. We find SnO
2
nanoparticles of tetragonal structure and sizes varying from 10 to 50 nm. The composition of SnO
2
nanoparticles is studied using x-ray photoelectron spectroscopy. We find a significant deviation from
the bulk SnO
2
composition pointing towards a different surface stoichiometry or termination.
