5.4 Solvothermal Method
91
Fig. 5.6 A Schematic of hierarchical α-Ni(OH) 2 microspheres synthesis. Reprinted from Ref.
Wang et al. (2018), copyright 2018, with permission from Elsevier. B Representative TEM images
of the samples obtained after reaction for a 4 h, b 6 h, c 10 h and d 12 h. e The corresponding
schematic illustration of the formation process for hierarchical NiCo-LDH tetragonal microtubes.
Reprinted from Ref. Ma et al. (2016), copyright 2016, with permission from The Royal Society of
Chemistry
In addition, ultra-small, crystalline, as well as dispersible NiO nanoparticles
were successfully synthesized by Fominykh for the first time. What’s more,
they are promising candidates as catalysts for electrochemical water oxidation
(Fominykh et al. 2014). Very small nickel oxide nanocrystals can be made, through
a solvothermal reaction in tert-butano, the sizes of which are tunable from 2.5 to
5 nm and have a narrow particle size distribution. Even after drying, the crystals are perfectly dispersible in ethanol, which shows stable transparent colloidal
dispersions. The structure of the nanocrystals is in accord with phase-pure stoichiometric nickel(II) oxide with a partially oxidized surface exhibiting Ni(III) states. The
3.3 nm nanoparticles demonstrate a remarkably high turn-over frequency of 0.29 s
−1
91
Fig. 5.6 A Schematic of hierarchical α-Ni(OH) 2 microspheres synthesis. Reprinted from Ref.
Wang et al. (2018), copyright 2018, with permission from Elsevier. B Representative TEM images
of the samples obtained after reaction for a 4 h, b 6 h, c 10 h and d 12 h. e The corresponding
schematic illustration of the formation process for hierarchical NiCo-LDH tetragonal microtubes.
Reprinted from Ref. Ma et al. (2016), copyright 2016, with permission from The Royal Society of
Chemistry
In addition, ultra-small, crystalline, as well as dispersible NiO nanoparticles
were successfully synthesized by Fominykh for the first time. What’s more,
they are promising candidates as catalysts for electrochemical water oxidation
(Fominykh et al. 2014). Very small nickel oxide nanocrystals can be made, through
a solvothermal reaction in tert-butano, the sizes of which are tunable from 2.5 to
5 nm and have a narrow particle size distribution. Even after drying, the crystals are perfectly dispersible in ethanol, which shows stable transparent colloidal
dispersions. The structure of the nanocrystals is in accord with phase-pure stoichiometric nickel(II) oxide with a partially oxidized surface exhibiting Ni(III) states. The
3.3 nm nanoparticles demonstrate a remarkably high turn-over frequency of 0.29 s
−1