I have read two different kinds of definitions for 0, 1, 2, and 3 D nanoparticles. In one type 1 D nanoparticle is defined as the particle which has only one dimension in nanometer scale eg. nanosheets, or thin films. In the other type, 1 D nanoparticle is defined as the particle in which electrons are allowed to move in only one direction and are confined in any two directions (x&y, y&z, x&z) eg. nanowires and nanotubes.

Similarly, for 2D, according to first kind of definition, two dimensions should be in nm scale then the example will be nanofibres or nanotubes. And if we consider other definitions i.e. electrons will be allowed to move in two directions only, then examples will be thin films or nanosheets.

Now, everything boils down to 0 or 3D nanoparticles. Please someone make it clear.