Self-assembly of β-Ni(OH)2 nanoflakelets to form hollow submicrospheres by hydrothermal route

Nickel hydroxide (Ni(OH)2) hollow microspheres were fabricated by template-free approach, in which the in situ formed β-Ni(OH)2 nanoflakelets serve as the building blocks and were self-assembled to form the hollow microspheres. Surface morphology and crystal structure analyses have confirmed that the Ni(OH)2 nanoflakelets are thin, transparent and of hexagonal crystal (β-) phase. The optical bandgap of Ni(OH)2 microspheres was found to be about 4.2 eV and the photoluminescence (PL) emission broadband was observed with peak maximum at around 395 nm. The spherical microstructures of β-Ni(OH)2 with hollow interiors may have possible application in the development of high-performance battery.