%0 Journal Article
%A Ramos Ramos, Diego J.
%A Vásquez Villanueva, G. Cristian
%A Maestre Varea, David
%T Micro-and nanocrystalline NiO synthesized by Joule heating and thermal oxidation methods: a comparative study
%D 2025
%@ 1528-7505
%U https://hdl.handle.net/20.500.14352/131138
%X The high stability and intrinsic p-type nature of nickel oxide (NiO) make it an interesting material for modern oxide-based technology microdevices. Nowadays, the industry demands more sustainable, highly efficient, and low-energy-consumption synthesis routes as an alternative to conventional methods that commonly involve high temperatures for long times or complex chemical routes. In this work, a fast, low-cost, and energy-saving synthesis based on the Joule heating (JH) process has been employed for the fabrication of micro- and nanocrystalline NiO. The as-grown NiO samples have been investigated as a function of the growth parameters, and special attention has been paid to the differences and similarities between microcrystals grown by JH or vapor-solid (VS) thermal treatments. In particular, Raman spectroscopy reveals that the JH process results in a very reproducible and controllable NiO microcrystalline structure as compared to VS regardless of the fast oxidation process. Cross-sectional analysis of the NiO grown by JH confirms the presence of inner/outer regions with variable microstructure, composition, and physical properties as a function of the different oxidation conditions promoted during the JH process. The mechanisms underlying the JH process have been discussed and compared with those related to the VS method.
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