Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (06): 1260-1265.doi: 10.3866/PKU.WHXB201303262

• SOFT MATTER • Previous Articles     Next Articles

Experimental Measurements of the Surface Effective Charge of Colloidal Particles

ZHOU Hong-Wei1, MI Li1,2, LIU Li-Xia1, XU Sheng-hua1, SUN Zhi-Wei1   

  1. 1 Key Laboratory of Microgravity, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, P. R. China;
    2 College of Chemistry, Chemical Engineering and Material Science, Shandong Normal University, Jinan 250014, P. R. China
  • Received:2012-12-27 Revised:2013-03-26 Published:2013-05-17
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (11172302, 11032011).


The effective surface charge of colloidal particles is an important parameter for calculating inter-particle interaction potentials. In this study, we investigated the effective charge of seven kinds of polystyrene particles having different diameters and surface charges. Two methods, conductivity-number density relationships and conductometric titration, were used to measure the effective charges. The results obtained from the two different methods show small variations of 7%. The effective charges were also calculated from empirical formulas and found to be twice as large as the experimental values, indicating these formulas cannot be universally applied to all colloidal dispersions.

Key words: Colloidal crystal, Effective charge, Interaction, Conductometric titration


  • O648