How to reduce the coffee ring effect during evaporation of aqueous solution?
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To reduce the coffee ring effect during the evaporation of aqueous solutions, several methods have been proposed. One approach is to use laser-induced differential evaporation, where a CO2 laser is used to engineer the liquid evaporation profile, transitioning particle deposition patterns from coffee-ring patterns to central-peak patterns . Another method involves coating the substrate with a thin layer of silicone oil, which prevents the periphery of the droplet from getting pinned to the substrate and helps in suppressing the ring formation . Additionally, the use of controlled evaporative self-assembly (CESA) in a confined geometry allows for a high degree of control over the drying dynamics and related flows, resulting in the creation of complex deposit patterns with a regularity that has never before been possible . Furthermore, covalent cross-linking of monodisperse materials can impede the coffee-ring effect by triggering gelation of the coating materials, counterbalancing the capillary forces induced by evaporation . Lastly, the vapor-driven solutal Marangoni effects of a binary mixture drop in a confined chamber can be utilized to control the nucleation location of surfactant crystallization, suppressing the conventional coffee-ring flow .
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42 Citations | The paper suggests that the coffee ring effect can be reduced during evaporation of an aqueous solution by depositing the droplet on a glass substrate coated with a thin layer of silicone oil. This prevents the periphery of the droplet from getting pinned to the substrate and helps in suppressing the ring formation. |
| The paper provides a method to reduce the coffee-ring effect during evaporation of aqueous solutions by triggering gelation of the coating materials via a thioacetate-disulfide transition. | |
| The paper provides a method called laser-induced differential evaporation to reduce the coffee-ring effect during evaporation of aqueous solutions. | |
1 Citations | The paper proposes using the vapor-driven solutal Marangoni effects of a binary mixture drop in a confined chamber to suppress the coffee-ring effect during evaporation of aqueous solutions. |
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