Speaker
Mr
Crispin Mbulanga
(Nelson Mandela Metropolitan University)
Description
Gel-oxidation method is a thermochemical method used to modify and form surface layers on Ti surface by controlling the thickness and morphology of surfaces. It can be described in terms of the following two-step process: (i) gelation: a Titanium based hydrogel is formed on Ti surface from corrosive reagent such as NaOH, KOH, LiOH, H2O2, …; and (ii) oxidation: the hydrogel is oxidised at various temperatures, thereby forming a surface layer of recrystallized titania (TiO2) and possibly other phases, such as alkaline (Na, …) titanate, on the surface [1] [2] [3] [4]. Hence, the aim of the present investigation is to explore the formation mechanism that leads to the synthetisation of TiO2 nanorods on metallic substrate, in particular Ti foil surface by gel-oxidation NaOH based method.
From XRD, SEM, TEM and Raman spectroscopy investigations, the following observations were made: (1) On the surface of Ti foil treated in 5 M NaOH solution at 76 oC for 24 h, there is a porous network morphology made of predominantly amorphous with a small amount of nanocrystalline; (2) anatase and rutile TiO2 nanorods formation take place on the surface of NaOH-treated Ti foil calcinated (oxidised) at 600 and 800 oC under a N2 flow; (3) rutile TiO2 nanostructures formation take place efficiently on the surface of NaOH-treated Ti foil calcinated (oxidised) at 800 oC under a N2 flow. After a careful interpretation of above results, it is understood that TiO2 fabricated nanorods inherited their morphology from Na Titanates.
References
[1] H.Z. Abdullah, P. Koshy and C.C. Sorrell, "Gel Oxidation of Titanium for Biomedical Application," Adv. Mater. Res., vol. 620, p. 122, 2013.
[2] H.Z. Abdullah and C.C. Sorrel, "Gel Oxidation Of Titanium And Effect Of UV Irradiation On Precipitation Of Hydroxyapatite From Simulated Body Fluid," Advanced Materials Research, Vols. 488-489, p. 1229, 2012.
[3] Hyun-Min Kim, F. Miyaji, T.Kokubo,' and T. Nakamura, "Preparation of bioactive Ti and its alloys via simple chemical surface treatment," J. Biomed.l Mater. Res., vol. 32, p. 409, 1996.
Apply to be<br> considered for a student <br> award (Yes / No)?
No
Main supervisor (name and email)<br>and his / her institution
J.R. Botha, , Nelson Mandela Metropolitan University
Level for award<br> (Hons, MSc, <br> PhD, N/A)?
N/A
Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?
No
Primary author
Mr
Crispin Mbulanga
(Nelson Mandela Metropolitan University)
Co-author
Mr
Stive Roussel Tankio Djiokap
(Nelson Mandela Metropolitan University)
