Figure 9.
Representative images of the morphologies discussed in this review: (a) Light micrograph of an electrochemically precipitated α-Ni(OH)2 film. The surface visibly cracked when the film was dried. Adapted with permission from [38]. (b) SEM image of β-Ni(OH)2 nanoflowers prepared by hydrothermal synthesis. Inset: high magnification shows the nanoflowers are composed of nanosheets. Adapted by permission from [22]. (c) TEM image of a ‘dandelion-like’ hollow β-Ni(OH)2 microsphere prepared by a sol–gel method. Reprinted with permission from [116], © 2009 American Chemical Society. (d) SEM of an ‘unusually large β-Ni(OH)2 ‘pseudo-single crystal’ prepared by a chemical precipitation method. Inset: high magnification of the particle basal plane and an edge. Reprinted with permission from [117], © 2011 American Chemical Society. (e) TEM image of α-Ni(OH)2 nanoribbons prepared by hydrothermal synthesis. Ribbons are 10–20 nm thick. Adapted with permission from [118]. © 2008 WILEY-VCH Verlag GmbH & Co. (f) SEM image of β-Ni(OH)2 nanoflowers prepared by microwave-assisted hydrothermal synthesis. Inset: high magnification of a single nanoflower. Reprinted from [119], © 2010, with permission from The Society of Powder Technology. (Online version in colour.)