On September 2, 2025, Prof. Wang Dayang from Jilin University was invited to visit the Institute of New Concept Sensors and Molecular Materials and presented a report titled “Van der Waals Emulsions: The Particle Size Effect as the Blind Spot of Pickering Emulsions in Hindsight”.

Prof. Wang’s report focuses on a novel mechanism for stabilizing emulsions at the oil-water interface using hydrophilic nanoparticles. Traditional Pickering emulsion stabilization relies on the adsorption energy of solid particles at the interface, making highly hydrophilic particles ineffective for emulsion stabilization due to excessively small contact angles. Prof. Wang’s team discovered that by adjusting the pH value of the system to reduce electrostatic repulsion between charged particles and oil droplets to near zero, strongly hydrophilic nanoparticles can efficiently maintain stable oil-in-water emulsions for months. This is primarily due to van der Waals forces between oil droplets and encapsulated particles. This mechanism significantly diverges from the “energy barrier-dominated” understanding in traditional Pickering emulsion stabilization theory, offering new insights for emulsion preparation and stabilization technology.

The session was hosted by Prof. Peng Junxia, with over 30 faculty members and students from the institute in attendance.