Abstract: An air treatment device and a control method are provided. The air treatment device includes a water tank assembly, a water trough and a sterilization device. The sterilization device includes a sterilization portion, the sterilization portion is provided in the water trough, a water replenishing switch is provided between the water tank assembly and the water trough, and the water replenishing switch is configured to control connection and disconnection between the water tank assembly and the water trough. The air treatment device further includes a control portion, and the control portion is capable of controlling an opening and closing of the sterilization portion according to an on-off state of the water replenishing switch to ensure a good sterilization effect.

Abstract: Some embodiments of the present disclosure provide a water retaining structure and a humidifier with the water retaining structure. The water retaining structure is disposed on a bottom surface of a water tank assembly. The water retaining structure and the water tank assembly are split. The water retaining structure includes a mist collecting portion and a water retaining portion. The mist collecting portion is formed into a mist collecting space. The mist collecting space communicates with a mist outlet tube in the water tank assembly. The water retaining portion is configured to collect water flowing down from the mist outlet tube. The water retaining structure and the water tank assembly are split so that the bottom surface of the water tank assembly is configured as a flat surface, or a height of a structure disposed on the bottom surface is reduced.