According to the valid definitions in ISO/TS 27687: August 2008 and the standardl particle definitions in accordance with ISO TC 24/SC 4, TC 146 and TC 209 there is a clear definition of nano particles respectively nano objects. Only for these nano objects, where one, two or three external dimensions are in the nanometer range below 100nm, the term nano particles should be used.
All coarser particles are submicron particles and should not be called nano particles anymore. The same is valid for so called nano structured material, which is aggregated from nano objects. Continue reading
NANO is an in many cases even in technical literature incorrectly used term. The Technical Committee 229 of ISO is deserving thanks for an exact definition with respect to particle size measurement in August 2008. (ISO/TS27687).
According to this definition only NANO-objects should be called NANO-particles if its three coordinate dimensions are all within the NANO-range of about 1 nm to 100 nm.
Regrettably even today many scientific publications still use the NANO-term in very imprecise manners. One reason for this might be the difficulty to measure NANO-Particles sufficiently precise. Imprecise knowledge of dimensions often leads to inaccurate classification. Continue reading