Authors: M. Bumiller, T. DeLuca, K. Mattison and A. Rawle
Affilation: Malvern Instruments Inc., United States
Pages: 381 - 384
Keywords: particle size analysis, carbon nanotubes, bucky balls, metal oxides
Purpose: Novel materials with single particle dimensions at the nano scale are submitted to our laboratory on a regular basis. These samples include single walled nanotubes (SWNT), buckyballs, quantum dots and various metal oxides. Determining the proper dispersion and test conditions to characterize nanomaterials is challenging. This poster summarizes our experiences and the general methodology devised for handling unknown samples. <br> <br>Method: A sedimentation screening technique is used to determine rough particle size, which then points towards appropriate technique. Laser diffraction was implemented for samples where the mean size is expected to exceed one micron and Photon Correlation Spectroscopy (dynamic light scattering) was used for submicron samples. Dilution studies were performed to understand the effect of dilution and to characterize the particle – particle interactions. Dispersion techniques included surfactants to wet powders, ultrasound to disperse particles to the primary state, acids to dissolve loosely bound agglomerates and admixtures were used to keep particles from re-agglomerating.<br> <br>Results: Particle size results from all categories of samples are presented in pre-dispersed and dispersed states. Guidelines are provided based on our laboratory’s experience from measuring over 100 nanoscale materials.