Time-resolved SAXS characterization of the shell growth of silica-coated magnetite nanocomposites
Source abstract
Abstract
Time-resolved characterization of silica-coated magnetite nanoparticles during synthesis is performed using our self-developed small-angle X-ray scattering (SAXS) instrument. The shell growth (5–20 nm) is determined quantitatively using a core–shell sphere model. SAXS analyses provide reliable information on the shell thickness despite the complex geometry of the synthesized nanocomposites. They are in good agreement with transmission electron microscope (TEM) observations. Firstly, time-resolved SAXS analyses are used to study the influence of the precursor concentration (tetraethyl orthosilicate) on growth kinetics. Time evolution of the shell thickness can be described by diffusion-limited shell growth, obeying kinetics of first order in the precursor concentration. Furthermore, SAXS measurements provide information on the standard deviation of the shell thickness as a function of the coating time. Its decrease observed with increasing coating time is explained by a self-sharpening mechanism and/or a morphology evolution to more isometric shapes. Additionally, the influence of ammonia is studied. By increasing its concentration, the growth rate is affected. However, the final shell thickness and the standard deviation do not change significantly. For low ammonia concentration, by contrast, the SAXS and TEM observations reveal superimposed silica gelation. In addition, coating reaction was conducted at elevated temperature (40 °C). SAXS patterns measured as a function of the coating time and TEM micrographs reveal simultaneous production of classic Stober particles under these conditions. Hence, SAXS is found to have a big potential for on-line monitoring of the shell properties.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Magnetic Properties and Synthesis of Ferrites · Iron oxide chemistry and applications · Nanoparticle-Based Drug Delivery
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (32)
Show source-provided references
1. Beaucage G (1996) Small-angle scattering from polymeric mass fractals of arbitrary mass-fractal dimension. J Appl Crystallogr 29:134–146. doi: 10.1107/s002188989501160510.1107/S0021889895011605 ↗
2. Boukari H, Lin JS, Harris MT (1997a) Probing the dynamics of the silica nanostructure formation and growth by SAXS. Chem Mater 9(11):2376–2384. doi: 10.1021/cm970287810.1021/cm9702878 ↗
3. Boukari H, Lin JS, Harris MT (1997b) Small-angle X-ray scattering study of the formation of colloidal silica particles from alkoxides: primary particles or not? J Colloid Interface Sci 194(2):311–318. doi: 10.1006/jcis.1997.511210.1006/jcis.1997.5112 ↗
4. Bruce IJ, Taylor J, Todd M, Davies MJ, Borioni E, Sangregorio C, Sen T (2004) Synthesis, characterisation and application of silica-magnetite nanocomposites. J Magn Magn Mater 284:145–160. doi: 10.1016/j.jmmm.2004.06.03210.1016/j.jmmm.2004.06.032 ↗
5. Caruana L, Costa AL, Cassani MC, Rampazzo E, Prodi L, Zaccheroni N (2012) Tailored SiO2-based coatings for dye doped superparamagnetic nanocomposites. Colloid Surf A 410:111–118. doi: 10.1016/j.colsurfa.2012.06.02710.1016/j.colsurfa.2012.06.027 ↗
6. Chen ZH, Hwang SH, Zeng X-b, Roh J, Jang J, Ungar G (2013) SAXS characterization of polymer-embedded hollow nanoparticles and of their shell porosity. J Appl Crystallogr 46:1654–1664. doi: 10.1107/s002188981302513210.1107/S0021889813025132 ↗
7. Debye P (1915) Zerstreuung von Röntgenstrahlen. Ann Phys 46:80910.1002/andp.19153510606 ↗
8. Deng YH, Wang CC, Hu JH, Yang WL, Fu SK (2005) Investigation of formation of silica-coated magnetite nanoparticles via sol–gel approach. Colloid Surf A 262(1–3):87–93. doi: 10.1016/j.colsurfa.2005.04.00910.1016/j.colsurfa.2005.04.009 ↗
9. Ding HL, Zhang YX, Wang S, Xu JM, Xu SC, Li GH (2012) Fe3O4@SiO2 core/shell nanoparticles: the silica coating regulations with a single core for different core sizes and shell thicknesses. Chem Mater 24(23):4572–4580. doi: 10.1021/cm302828d10.1021/cm302828d ↗
10. Elingarami S, Zeng X (2011) A short review on current use of magnetic nanoparticles for bio-separation, sequencing, diagnosis and drug delivery. Adv Sci Lett 4(11–12):3295–3300. doi: 10.1166/asl.2011.188410.1166/asl.2011.1884 ↗
11. Glatter O, Kratky O (1982) Small angle X-ray scattering. Academic, London
12. Goertz V, Dingenouts N, Nirschl H (2009) Comparison of nanometric particle size distributions as determined by SAXS, TEM and analytical ultracentrifuge. Part Part Syst Charact 26(1-2):17–24. doi: 10.1002/ppsc.20080000210.1002/ppsc.200800002 ↗
13. Goertz V, Gutsche A, Dingenouts N, Nirschl H (2012) Small-angle X-ray scattering study of the formation of colloidal SiO2 Stober multiplets. J Phys Chem C 116(51):26938–26946. doi: 10.1021/jp311187510.1021/jp3111875 ↗
14. Gregory AP, Clarke RN, Cox MG (2009) Traceable measurement of dielectric reference liquids over the temperature interval 10–50 °C using coaxial-line methods. Meas Sci Technol 20(7):075106. doi: 10.1088/0957-0233/20/7/07510610.1088/0957-0233/20/7/075106 ↗
15. Guinier A, Fournet G (1955) Small-angle scattering of X-rays. Wiley, New York
16. Guo X, Gutsche A, Nirschl H (2013a) SWAXS investigations on diffuse boundary nanostructures of metallic nanoparticles synthesized by electrical discharges. J Nanopart Res 15(11):1–13. doi: 10.1007/s11051-013-2058-7
17. Guo X, Gutsche A, Wagner M, Seipenbusch M, Nirschl H (2013b) Simultaneous SWAXS study of metallic and oxide nanostructured particles. J Nanopart Res 15(4):1–3. doi: 10.1007/s11051-013-1559-8
18. Hasany SF, Abdurahman NH, Sunarti AR, Jose R (2013) Magnetic iron oxide nanoparticles: chemical synthesis and applications review. Curr Nanosci 9(5):561–57510.2174/15734137113099990085 ↗
19. Jeong U, Teng X, Wang Y, Yang H, Xia Y (2007) Superparamagnetic colloids: controlled synthesis and niche applications. Adv Mater 19(1):33–60. doi: 10.1002/adma.20060067410.1002/adma.200600674 ↗
20. Liu B, Wang D-P, Huang W-H, Yao A-H, Koji I (2008) Preparation of core–shell SiO2/Fe3O4 nanocomposite particles via sol–gel approach. J Inorg Mater 23(1):33–3810.3724/SP.J.1077.2008.00033 ↗
21. Massart R (1981) Preparation of aqueous magnetic liquids in alkaline and acidic media. IEEE Trans Magn 17(2):1247–1248. doi: 10.1109/tmag.1981.106118810.1109/TMAG.1981.1061188 ↗
22. Mine E, Yamada A, Kobayashi Y, Konno M, Liz-Marzan LM (2003) Direct coating of gold nanoparticles with silica by a seeded polymerization technique. J Colloid Interface Sci 264(2):385–390. doi: 10.1016/s0021-9797(03)00422-310.1016/S0021-9797(03)00422-3 ↗
23. Philipse AP, Vanbruggen MPB, Pathmamanoharan C (1994) Magnetic silica dispersions—preparation and stability of surface-modified silica particles with a magnetic core. Langmuir 10(1):92–99. doi: 10.1021/la00013a01410.1021/la00013a014 ↗
24. Pontoni D, Narayanan T, Rennie AR (2002) Time-resolved SAXS study of nucleation and growth of silica colloids. Langmuir 18(1):56–59. doi: 10.1021/la015503c10.1021/la015503c ↗
25. Roshan Deen G, Oliveira CLP, Pedersen JS (2009) Phase behavior and kinetics of phase separation of a nonionic microemulsion of C12E5/water/1-chlorotetradecane upon a temperature quench. J Phys Chem B 113(20):7138–7146. doi: 10.1021/jp808268m10.1021/jp808268m ↗
26. Safarik I, Safarikova M (2002) Magnetic nanoparticles and biosciences. Monatsh Chem 133(6):737–759. doi: 10.1007/s00706020004710.1007/s007060200047 ↗
27. Shinkai M (2002) Functional magnetic particles for medical application. J Biosci Bioeng 94(6):606–613. doi: 10.1016/s1389-1723(02)80202-x10.1016/S1389-1723(02)80202-X ↗
28. Stöber W, Fink A, Bohn E (1968) Controlled growth of monodispersed silica spheres in micron size range. J Colloid Interface Sci 26(1):62. doi: 10.1016/0021-9797(68)90272-510.1016/0021-9797(68)90272-5 ↗
29. Sugimoto T (1987) Preparation of monodispersed colloidal particles. Adv Colloid Interface Sci 28(1):65–108. doi: 10.1016/0001-8686(87)80009-x10.1016/0001-8686(87)80009-X ↗
30. Tobler DJ, Benning LG (2013) In situ and time resolved nucleation and growth of silica nanoparticles forming under simulated geothermal conditions. Geochim Cosmochim Acta 114:156–168. doi: 10.1016/j.gca.2013.03.04510.1016/j.gca.2013.03.045 ↗
31. Wengeler R, Wolf F, Dingenouts N, Nirschl H (2007) Characterizing dispersion and fragmentation of fractal, pyrogenic silica nanoagglomerates by small-angle X-ray scattering. Langmuir 23(8):4148–4154. doi: 10.1021/la063073q10.1021/la063073q ↗
32. Zhang X-l, Niu H-y, Li W-h, Shi Y-l, Cai Y-q (2011) A core-shell magnetic mesoporous silica sorbent for organic targets with high extraction performance and anti-interference ability. Chem Commun 47(15):4454–4456. doi: 10.1039/c1cc10300h10.1039/c1cc10300h ↗