How long do nanobubbles typically last, and what factors can affect their lifetime?

The lifetime of nanobubbles can vary depending on several factors. In general, nanobubbles are considered to be short-lived, with half-lives ranging from a few seconds to a few minutes. However, some studies have reported persistence of nanobubbles up to several hours or even days.

Factors that may affect the lifetime of nanobubbles include:

• Type of gas: The gas used to fill the nanobubbles can affect their stability. For example, nanobubbles filled with oxygen or air tend to be less stable than those filled with more inert gases like nitrogen.

• Surface properties: The surface properties of the nanobubbles can affect their stability. For example, if the surface of the nanobubble is charged or coated with a stabilizing agent, this can help prevent the bubble from collapsing.

• Temperature: Higher temperatures can increase the rate of gas diffusion out of the nanobubbles, causing them to collapse more quickly.

• Pressure: Changes in pressure can also affect the stability of nanobubbles. For example, a decrease in pressure can cause the nanobubbles to expand and eventually burst.

• Ultrasound exposure: Exposure to ultrasound waves can cause the nanobubbles to oscillate and eventually collapse, which can shorten their lifespan.

It’s important to note that nanobubble lifetime may also depend on the specific application and how the nanobubbles are used.