The need to easily and quickly count larger numbers of nanoparticles, in order to obtain statistically useful size and size-distribution data, is addressed via the use of a readily available, free, public-domain program for particle counting, NIH-Image (and 2 others derived from it, Scion Image and Image J), collectively referred to herein as Image. The best protocols that we have found useful for the use of Image are reported; both appropriate as well as problematic applications of Image are then illustrated with a series of TEM images of Ir(0), Pd(0) and Au(0) nanoclusters. Methods to detect and image nanoclusters with sub-1-nm core diameters are reported and illustrated in the literature with Au nanoclusters, an important problem since the literature indicates that subnanometer Au nanoclusters are often present, but undetected. A list of suggestions and caveats for the appropriate use of Image is also provided, since this contribution is directed at first-time users who are not presently using nanoparticle imaging software. The reader is also reminded of several, well-known caveats for the use of TEM in obtaining size data for nanostructures. Overall, Image is a free, public-domain program that is useful for the rapid counting of large numbers of particles.

The need to easily and quickly count larger numbers of nanoparticles, in order to obtain statistically useful size and size-distribution data, is addressed via the use of a readily available, free, public-domain program for particle counting, NIH-Image (and 2 others derived from it, Scion Image and Image J), collectively referred to herein as Image. The best protocols that we have found useful for the use of Image are reported; both appropriate as well as problematic applications of Image are then illustrated with a series of TEM images of Ir(0), Pd(0) and Au(0) nanoclusters. Methods to detect and image nanoclusters with sub-1-nm core diameters are reported and illustrated in the literature with Au nanoclusters, an important problem since the literature indicates that subnanometer Au nanoclusters are often present, but undetected. A list of suggestions and caveats for the appropriate use of Image is also provided, since this contribution is directed at first-time users who are not presently using nanoparticle imaging software. The reader is also reminded of several, well-known caveats for the use of TEM in obtaining size data for nanostructures. Overall, Image is a free, public-domain program that is useful for the rapid counting of large numbers of particles.