Abstract: Sol preparation has been introduced as a fundamental concept since secondary education and subsequently developed into a classical physical chemistry experiment at the undergraduate level. However, traditional experimental designs have exhibited several limitations, including oversimplified preparation methods, inadequate structural and performance characterization of colloids, and insufficient consideration of practical applications, failing to keep pace with rapid advancements in the field. In our recent teaching practice, we have implemented significant improvements to this experiment. Firstly, we eliminated obsolete components while enhancing the environmental sustainability of the experimental procedure. More importantly, we incorporated surfactant-mediated control of colloidal particle growth during preparation, expanded the characterization methods for colloidal materials, and demonstrated their application in soft matter structural modulation using hydrogel additives as an example. The redesigned experiment features extended scope, enhanced comprehensiveness, and improved knowledge integration, enabling students to broaden their perspectives, gain deeper insights into structure-property relationships of colloidal materials, develop comprehensive experimental skills, and strengthen their understanding of colloidal systems.

Key words: Colloid, Physical chemistry, Surfactant, Hydrogel, Soft matter