1. NTNU Nanomechanical Lab, Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
2. Laboratory of Surface and Interface Physics (LSIP), Applied Physics Department, Faculty of Sciences, University of Granada, Campus de Fuentenueva s/n, ES-18071 Granada, Spain
3. Department of Physics, Research Institute for Biomimetics and Soft Matter, Fujian Provincial Key Laboratory for Soft Functional Materials Research, Xiamen University, Xiamen 361005, P. R. China
4. Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway