Superhydrophobic surfaces often lose the easy-removal ability of liquids during icing&melting cycles due to the impalement phenomena of air pockets.Especially for the most common mixed liquids in normal life,their...Superhydrophobic surfaces often lose the easy-removal ability of liquids during icing&melting cycles due to the impalement phenomena of air pockets.Especially for the most common mixed liquids in normal life,their difficult-removals after icing and melting have brought colossal troubles in the fields of aviation,energy,biomedicine,etc.Here we adopt the ultrafast laser to fabricate the optimal micro-nanostructured surfaces,realizing excellent superomniphobicity for seven environmental-related liquids.It is demonstrated that different droplets on the surfaces recover well to the original Cassie-Baxter state after melting,and can be removed easily at low tilted angles.The ice adhesion strengths of the seven liquids as low as 5 kPa and the micro-nanostructure durability ensure the long-term easy-removal after icing.Compared with the ice adhesion strength of untreated surfaces(264.4±17.6 kPa),those of our designed surfaces have decreased by over 50 times.Icing and melting processes are investigated to reveal the easy-removal mechanisms that specifically distributed solutes and bubbles after icing impact downwards significantly to accelerate the recovery of the Cassie–Baxter state during melting.A series of environmental-related durability experiments including continuous icing&melting cycles,long-term salt spray,and high-pressure water jet impact further demonstrate the surfaces promising for real applications.展开更多
Controllable fabrication of surface micro/nano structures is the key to realizing surface functionalization for various applications.As a versatile approach,ultrafast laser ablation has been widely studied for surface...Controllable fabrication of surface micro/nano structures is the key to realizing surface functionalization for various applications.As a versatile approach,ultrafast laser ablation has been widely studied for surface micro/nano structuring.Increasing research eforts in this feld have been devoted to gaining more control over the fabrication processes to meet the increasing need for creation of complex structures.In this paper,we focus on the in-situ deposition process following the plasma formation under ultrafast laser ablation.From an overview perspective,we frstly summarize the diferent roles that plasma plumes,from pulsed laser ablation of solids,play in diferent laser processing approaches.Then,the distinctive in-situ deposition process within surface micro/nano structuring is highlighted.Our experimental work demonstrated that the in-situ deposition during ultrafast laser surface structuring can be controlled as a localized micro-additive process to pile up secondary ordered structures,through which a unique kind of hierarchical structure with fort-like bodies sitting on top of micro cone arrays were fabricated as a showcase.The revealed laser-matter interaction mechanism can be inspiring for the development of new ultrafast laser fabrication approaches,adding a new dimension and more fexibility in controlling the fabrication of functional surface micro/nano structures.展开更多
基金the National Key Research and Development Program of China(No.2017YFB1104300)the Tsinghua University Initiative Scientific Research Program(No.2018Z05JZY009)the National Natural Science Foundation of China(Nos.51575309 and 51210009).
文摘Superhydrophobic surfaces often lose the easy-removal ability of liquids during icing&melting cycles due to the impalement phenomena of air pockets.Especially for the most common mixed liquids in normal life,their difficult-removals after icing and melting have brought colossal troubles in the fields of aviation,energy,biomedicine,etc.Here we adopt the ultrafast laser to fabricate the optimal micro-nanostructured surfaces,realizing excellent superomniphobicity for seven environmental-related liquids.It is demonstrated that different droplets on the surfaces recover well to the original Cassie-Baxter state after melting,and can be removed easily at low tilted angles.The ice adhesion strengths of the seven liquids as low as 5 kPa and the micro-nanostructure durability ensure the long-term easy-removal after icing.Compared with the ice adhesion strength of untreated surfaces(264.4±17.6 kPa),those of our designed surfaces have decreased by over 50 times.Icing and melting processes are investigated to reveal the easy-removal mechanisms that specifically distributed solutes and bubbles after icing impact downwards significantly to accelerate the recovery of the Cassie–Baxter state during melting.A series of environmental-related durability experiments including continuous icing&melting cycles,long-term salt spray,and high-pressure water jet impact further demonstrate the surfaces promising for real applications.
基金support by the National Key Research and Development Program of China(No.2017YFB1104300)the National Natural Science Foundation of China(Nos.51575309 and 51210009)the Tsinghua University Initiative Scientifc Research Program(No.2018Z05JZY009).
文摘Controllable fabrication of surface micro/nano structures is the key to realizing surface functionalization for various applications.As a versatile approach,ultrafast laser ablation has been widely studied for surface micro/nano structuring.Increasing research eforts in this feld have been devoted to gaining more control over the fabrication processes to meet the increasing need for creation of complex structures.In this paper,we focus on the in-situ deposition process following the plasma formation under ultrafast laser ablation.From an overview perspective,we frstly summarize the diferent roles that plasma plumes,from pulsed laser ablation of solids,play in diferent laser processing approaches.Then,the distinctive in-situ deposition process within surface micro/nano structuring is highlighted.Our experimental work demonstrated that the in-situ deposition during ultrafast laser surface structuring can be controlled as a localized micro-additive process to pile up secondary ordered structures,through which a unique kind of hierarchical structure with fort-like bodies sitting on top of micro cone arrays were fabricated as a showcase.The revealed laser-matter interaction mechanism can be inspiring for the development of new ultrafast laser fabrication approaches,adding a new dimension and more fexibility in controlling the fabrication of functional surface micro/nano structures.