Measurement of inorganic particle size using dynamic light scattering method.
アイテス
Dynamic light scattering allows for the measurement of particle size and size distribution of nanoparticles dispersed in a liquid without separating the particles. Here, we present examples of particle size measurement for silica and alumina particles in an aqueous medium. Particles in a solution exhibit Brownian motion that depends on their size, and the fluctuations in the scattered light caused by illuminating the particles are also size-dependent. By observing and analyzing these fluctuations, we can determine the particle size and size distribution. [Alumina Measurement Results and Discussion] - As alumina approaches neutrality from a strongly alkaline condition, it nears its isoelectric point. - The surface charge of the particles decreases. - The repulsion between particles diminishes. - It can be inferred that particle aggregation is occurring. [Silica Measurement Results and Discussion] - It is believed that the isoelectric point is on the strongly acidic side. - In the pH range of 3 to 10, particle aggregation does not occur. - Particle size is maintained below 50 nm.
