This paper presents a study on the combination of atomization and electrostatic charging to improve the collection efficiency of fine particles in a gas cyclone. A technology combining atomization and cyclones called cloud-air-purifying (CAP) has recently been developed, which utilizes the supersaturated vapor in the cyclone to realize the enlargement of dust particles and improve the collection efficiency. Here, the technology is further improved by charging the particles and droplets. Three different charging schemes are studied, including charging vapor droplets only, charging dust particles only, and charging both of them with opposite polarities. Experimental results indicate that all three charging schemes can significantly improve the collection efficiency. In particular, with charging, the collection efficiency of particles of approximately 2 mu m is mostly improved. Consequently, the combination of the CAP technology and electrostatic charging can be a promising novel method to effectively remove PM2.5. (C) 2020 Published by Elsevier B.V.