Electronic Supplementary Information ( ESI ) Ambient Rutile VO 2 ( R ) Hollow Hierarchitectures with Rich Grain Boundaries from New-State Nsutite-Type VO 2 , Displaying Enhanced Hydrogen Adsorption Behavior

S1. Shape evolution of the new-state VO 2 hollow spherical nanoarchitectures S2. Compositional characterization of the new-state nsutite-type VO 2 precursor S3. Summary XRD patterns of the nsutite-type VO 2 prepared by different chemical reactions S4. Structural determination of new-state VO 2 S5. Calculation details and phase conversion process from the new-state nsutite-type VO 2 to rutile VO 2 (R) S6. Characterization of the GBR-VO 2 (R) hollow hierarchitectures S7. Gas adsorption experiments of different vanadium oxides