A review on Colloidal Gas Aphrons (CGAs): Current status and future directions

Unique and versatile features of Colloidal Gas Aphrons (CGAs) or the surface-charged microbubbles have attracted extensive research efforts addressing applications across multiple domains, stimulating many technological advancements. This comprehensive review begins by providing insights into the distinct structure and noteworthy properties of CGAs, highlighting the important role played by operational parameters, such as type and concentration of surfactant, pH, temperature, pressure, mixing speed, mixing time, salinity, polymer addition, and geometrical aspects of components of CGAs generator. It takes the reader through many of the explored applications of CGAs, identifying the mechanisms involved in their successful implementation. In addition, it outlines the key challenges and provides recommendations for future studies. The present paper thus provides an overview of the current status of research on CGAs and their applications, and also indicates scope for future explorations.