1. School of Materials Science and Engineering Faculty of Science University of New South Wales (UNSW) Sydney NSW 2052 Australia
2. School of Photovoltaic and Renewable Energy Engineering University of New South Wales (UNSW) Sydney NSW 2052 Australia
3. Hefei National Laboratory for Physical Sciences at the Microscale Department of Physics University of Science and Technology of China (USTC) Hefei 230026 China
4. Solid State and Elemental Analysis Unit Mark Wainwright Analytical Centre University of New South Wales (UNSW) Sydney NSW 2052 Australia
5. Australian Nuclear Science and Technology Organisation Locked Bag 2001 Kirrawee DC NSW 2232 Australia
6. Electron Microscope Unit Mark Wainwright Analytical Centre University of New South Wales (UNSW) Sydney NSW 2052 Australia
7. School of Mathematical and Physical Sciences University of Technology Sydney Sydney NSW 2007 Australia
8. Departament de Física Universitat Politècnica de Catalunya Campus Nord B4‐B5 Barcelona E‐08034 Spain