1. Research Institution for Biomimetics and Soft MatterFujian Key Provincial Laboratory for Soft Functional Materials ResearchCollege of Physical Science and Technology & College of MaterialsXiamen University Xiamen 361005 P. R. China
2. Advanced Soft Matter GroupDepartment of Chemical EngineeringDelft University of Technology Van der Maasweg 9 Delft 2629 HZ The Netherlands
3. Department of PhysicsNational University of Singapore 2 Science Drive 3 Singapore 117542 Singapore