Abstract
In this paper we employ first-principles calculations to investigate the effect of substitutional Si doping in the amorphous calcium-phosphate (a-HAP) structure on the work of adhesion, integral charge transfer, charge density difference and theoretical tensile strengths between an a-HAP coating and amorphous titanium dioxide (a-TiO2) substrate systemically. Our calculations demonstrate that substitution of a P atom by a Si atom in a-HAP (a-Si-HAP) with the creation of OH-vacancies as charge compensation results in a significant increase of the bonding strength of the coating to the substrate. The work of adhesion of the optimized Si-doped interfaces reaches a value of up to −2.52 J m−2, which is significantly higher than for the stoichiometric a-HAP/a-TiO2. Charge density difference analysis indicates that the dominant interactions at the interface have significant covalent character, and in particular two Ti–O and three Ca–O bonds are formed for a-Si-HAP/a-TiO2 and one Ti–O and three Ca–O bonds for a-HAP/a-TiO2. From the stress-strain curve, the Young's modulus of a-Si-HAP/a-TiO2 is calculated to be about 25% higher than that of the a-HAP/a-TiO2, and the yielding stress is about 2 times greater than that of the undoped model. Our calculations therefore demonstrate that the presence of Si in the a-HAP structure strongly alters not only the bioactivity and resorption rates, but also the mechanical properties of the a-HAP/a-TiO2 interface. The results presented here provide an important theoretical insight into the nature of the chemical bonding at the a-HAP/a-TiO2 interface, and are particularly significant for the practical medical applications of HAP-based biomaterials.
| Original language | English |
|---|---|
| Pages (from-to) | 228-234 |
| Number of pages | 7 |
| Journal | Computational Materials Science |
| Volume | 159 |
| DOIs | |
| Publication status | Published - 1 Mar 2019 |
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Keywords
- Biomaterials
- Computer simulations
- Density functional theory (DFT)
- Hydroxyapatite-coated titanium
- Interface
- Tensile testing
ASJC Scopus subject areas
- Computer Science(all)
- Chemistry(all)
- Materials Science(all)
- Mechanics of Materials
- Physics and Astronomy(all)
- Computational Mathematics
Cite this
Effects of silicon doping on strengthening adhesion at the interface of the hydroxyapatite–titanium biocomposite : A first-principles study. / Grubova, Irina Yu; Surmeneva, Maria A.; Huygh, Stijn; Surmenev, Roman A.; Neyts, Erik C.
In: Computational Materials Science, Vol. 159, 01.03.2019, p. 228-234.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Effects of silicon doping on strengthening adhesion at the interface of the hydroxyapatite–titanium biocomposite
T2 - A first-principles study
AU - Grubova, Irina Yu
AU - Surmeneva, Maria A.
AU - Huygh, Stijn
AU - Surmenev, Roman A.
AU - Neyts, Erik C.
PY - 2019/3/1
Y1 - 2019/3/1
N2 - In this paper we employ first-principles calculations to investigate the effect of substitutional Si doping in the amorphous calcium-phosphate (a-HAP) structure on the work of adhesion, integral charge transfer, charge density difference and theoretical tensile strengths between an a-HAP coating and amorphous titanium dioxide (a-TiO2) substrate systemically. Our calculations demonstrate that substitution of a P atom by a Si atom in a-HAP (a-Si-HAP) with the creation of OH-vacancies as charge compensation results in a significant increase of the bonding strength of the coating to the substrate. The work of adhesion of the optimized Si-doped interfaces reaches a value of up to −2.52 J m−2, which is significantly higher than for the stoichiometric a-HAP/a-TiO2. Charge density difference analysis indicates that the dominant interactions at the interface have significant covalent character, and in particular two Ti–O and three Ca–O bonds are formed for a-Si-HAP/a-TiO2 and one Ti–O and three Ca–O bonds for a-HAP/a-TiO2. From the stress-strain curve, the Young's modulus of a-Si-HAP/a-TiO2 is calculated to be about 25% higher than that of the a-HAP/a-TiO2, and the yielding stress is about 2 times greater than that of the undoped model. Our calculations therefore demonstrate that the presence of Si in the a-HAP structure strongly alters not only the bioactivity and resorption rates, but also the mechanical properties of the a-HAP/a-TiO2 interface. The results presented here provide an important theoretical insight into the nature of the chemical bonding at the a-HAP/a-TiO2 interface, and are particularly significant for the practical medical applications of HAP-based biomaterials.
AB - In this paper we employ first-principles calculations to investigate the effect of substitutional Si doping in the amorphous calcium-phosphate (a-HAP) structure on the work of adhesion, integral charge transfer, charge density difference and theoretical tensile strengths between an a-HAP coating and amorphous titanium dioxide (a-TiO2) substrate systemically. Our calculations demonstrate that substitution of a P atom by a Si atom in a-HAP (a-Si-HAP) with the creation of OH-vacancies as charge compensation results in a significant increase of the bonding strength of the coating to the substrate. The work of adhesion of the optimized Si-doped interfaces reaches a value of up to −2.52 J m−2, which is significantly higher than for the stoichiometric a-HAP/a-TiO2. Charge density difference analysis indicates that the dominant interactions at the interface have significant covalent character, and in particular two Ti–O and three Ca–O bonds are formed for a-Si-HAP/a-TiO2 and one Ti–O and three Ca–O bonds for a-HAP/a-TiO2. From the stress-strain curve, the Young's modulus of a-Si-HAP/a-TiO2 is calculated to be about 25% higher than that of the a-HAP/a-TiO2, and the yielding stress is about 2 times greater than that of the undoped model. Our calculations therefore demonstrate that the presence of Si in the a-HAP structure strongly alters not only the bioactivity and resorption rates, but also the mechanical properties of the a-HAP/a-TiO2 interface. The results presented here provide an important theoretical insight into the nature of the chemical bonding at the a-HAP/a-TiO2 interface, and are particularly significant for the practical medical applications of HAP-based biomaterials.
KW - Biomaterials
KW - Computer simulations
KW - Density functional theory (DFT)
KW - Hydroxyapatite-coated titanium
KW - Interface
KW - Tensile testing
UR - http://www.scopus.com/inward/record.url?scp=85058437193&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85058437193&partnerID=8YFLogxK
U2 - 10.1016/j.commatsci.2018.12.026
DO - 10.1016/j.commatsci.2018.12.026
M3 - Article
AN - SCOPUS:85058437193
VL - 159
SP - 228
EP - 234
JO - Computational Materials Science
JF - Computational Materials Science
SN - 0927-0256
ER -