Strength of bubble walls and the Hall–Petch effect in bubble-spinning

Ashes are used as additives to strengthen bubble walls using the Hall–Petch effect and, as a result, a larger bubble can be produced in the bubble-spinning process, and it can last for a longer period. The fiber morphology can be easily controlled by the amount of ashes added. Two-dimensional nanobelts can be fabricated when the ashes ratio reaches a certain threshold.