Effect of two-step calcination on the formation of nickel oxide hollow nanofibers
Vinícius D. Silva,
Emanuel P. Nascimento,
João P.F. Grilo,
Thiago A. Simões,
Romualdo R. Menezes,
Daniel A. Macedo,
Eliton S. Medeiros
Affiliations
Vinícius D. Silva
Materials Science and Engineering Postgraduate Program, UFPB, 58051-900, João Pessoa, Brazil; Laboratory of Materials and Biosystems (LAMAB), UFPB, 58051-900, João Pessoa, Brazil; Corresponding author. Materials Science and Engineering Postgraduate Program, UFPB, 58051-900, João Pessoa, Brazil.
Emanuel P. Nascimento
Laboratory of Materials Technology (LTM), UFCG, 58429-900, Campina Grande, Brazil; Materials Science and Engineering Postgraduate Program, UFCG, 58429-900, Campina Grande, Brazil
João P.F. Grilo
Materials Science and Engineering Postgraduate Program, UFPB, 58051-900, João Pessoa, Brazil; Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193, Aveiro, Portugal
Thiago A. Simões
Materials Science and Engineering Postgraduate Program, UFPB, 58051-900, João Pessoa, Brazil; Center for Science and Technology in Energy and Sustainability (CETENS), UFRB, 44085-132, Feira de Santana, Brazil
Romualdo R. Menezes
Laboratory of Materials Technology (LTM), UFCG, 58429-900, Campina Grande, Brazil; Materials Science and Engineering Postgraduate Program, UFCG, 58429-900, Campina Grande, Brazil
Daniel A. Macedo
Materials Science and Engineering Postgraduate Program, UFPB, 58051-900, João Pessoa, Brazil; Corresponding author.
Eliton S. Medeiros
Materials Science and Engineering Postgraduate Program, UFPB, 58051-900, João Pessoa, Brazil; Laboratory of Materials and Biosystems (LAMAB), UFPB, 58051-900, João Pessoa, Brazil; Corresponding author. Materials Science and Engineering Postgraduate Program, UFPB, 58051-900, João Pessoa, Brazil.
1D (one-dimensional) hollow nanofibers are of great technological interest. Their formation can be controlled by tuning the calcination process. However, the formation mechanism through the control of the burning stage is still debated in the literature. Herein, the influence of calcination in two steps on the morphology of hollow nanofibers of nickel oxide (NiO), prepared by solution blow spinning (SBS) technique, was investigated. A systematic study using a variety of characterization techniques suggests that a prolonged residence time in the initial step of calcination produces nanofibers with a better definition of the hollow region with better control of tubular wall thickness. Statistically, the calcination methodology studied here does not affect the outer diameter of nanofibers, as shown by Analysis of Variance (ANOVA) and Tukey’s method. According to our findings, the formation mechanism is influenced by gas diffusion and phase separation during fiber spinning and heat treatment, which suggests that neither the Kirkendall effect nor the Ostwald ripening process can be solely responsible for the formation hollow fibers. These findings contribute to a better understanding of the formation of metal-oxide hollow nanofibers induced by heat treatment.
