1. Materials and Life Science Research DivisionKorea Institute of Science and Technology Seoul 02792 Republic of Korea
2. Advanced Analysis CenterKorea Institute of Science and Technology Seoul 02792 Republic of Korea
3. Center for Hydrogen‐Fuel Cell ResearchKorea Institute of Science and Technology Seoul 02792 Republic of Korea
4. Department of Materials Science and EngineeringKorea University Seoul 02841 Republic of Korea