Understanding bottom-up continuous hydrothermal synthesis of nanoparticles using empirical measurement and computational simulation


Continuous hydrothermal synthesis was highlighted in a recent review as an enabling technology for the production of nanoparticles. In recent years, it has been shown to be a suitable reaction medium for the synthesis of a wide range of nanomaterials. Many single and complex nanomaterials such as metals, metal oxides, doped oxides, carbonates, sulfides, hydroxides, phosphates, and metal organic frameworks can be formed using continuous hydrothermal synthesis techniques. This work presents a methodology to characterize continuous hydrothermal flow systems both experimentally and numerically, and to determine the scalability of a counter current supercritical water reactor for the large scale production (>1,000 T·year–1) of nanomaterials. Experiments were performed using a purpose-built continuous flow rig, featuring an injection loop on a metal salt feed line, which allowed the injection of a chromophoric tracer. At the system outlet, the tracer was detected using UV/Vis absorption, which could be used to measure the residence time distribution within the reactor volume. Computational fluid dynamics (CFD) calculations were also conducted using a modeled geometry to represent the experimental apparatus. The performance of the CFD model was tested against experimental data, verifying that the CFD model accurately predicted the nucleation and growth of the nanomaterials inside the reactor.

This is a preview of subscription content, access via your institution.


  1. [1]

    Hobson, D. W. Commercialization of nanotechnology. Wiley Interdiscip. Rev. Nanomed. Nanobiotechnol. 2009, 1, 189–202.

    Article  Google Scholar 

  2. [2]

    Seo, Y. H.; Jeong, S.; Jo, Y.; Choi, Y.; Ryu, B. H.; Han, G.; Lee, M. Long-term dispersion stability and adhesion promotion of aqueous Cu nano-ink for flexible printed electronics. J. Nanosci. Nanotechnol. 2013, 13, 5661–5664.

    Article  Google Scholar 

  3. [3]

    Syamchand, S. S.; Sony, G. Europium enabled luminescent nanoparticles for biomedical applications. J. Lumin. 2015, 165, 190–215.

    Article  Google Scholar 

  4. [4]

    Uludag, Y.; Köktürk, G. Determination of prostate-specific antigen in serum samples using gold nanoparticle based amplification and lab-on-a-chip based amperometric detection. Microchim. Acta 2015, 182, 1685–1691.

    Article  Google Scholar 

  5. [5]

    Middlemas, S.; Fang, Z. Z.; Fan, P. Life cycle assessment comparison of emerging and traditional titanium dioxide manufacturing processes. J. Clean. Prod. 2015, 89, 137–147.

    Article  Google Scholar 

  6. [6]

    Zhang, Y.; Zhang, L. Y.; Zhou, C. W. Review of chemical vapor deposition of graphene and related applications. Acc. Chem. Res. 2013, 46, 2329–2339.

    Article  Google Scholar 

  7. [7]

    Sebastian, V.; Arruebo, M.; Santamaria, J. Reaction engineering strategies for the production of inorganic nanomaterials. Small 2014, 10, 835–853.

    Article  Google Scholar 

  8. [8]

    Byrappa, K.; Adschiri, T. Hydrothermal technology for nanotechnology. Prog. Cryst. Growth Ch. 2007, 53, 117–166.

    Article  Google Scholar 

  9. [9]

    Adschiri, T.; Kanazawa, K.; Arai, K. Rapid and continuous hydrothermal crystallization of metal oxide particles in supercritical water. J. Am. Ceram. Soc. 1992, 75, 1019–1022.

    Article  Google Scholar 

  10. [10]

    Lester, E.; Blood, P.; Denyer, J.; Giddings, D.; Azzopardi, B.; Poliakoff, M. Reaction engineering: The supercritical water hydrothermal synthesis of nano-particles. J. Supercrit. Fluids. 2006, 37, 209–214.

    Article  Google Scholar 

  11. [11]

    Adschiri, T.; Hakuta, Y.; Sue, K.; Arai, K. Hydrothermal synthesis of metal oxide nanoparticles at supercritical conditions. J. Nanopart. Res. 2001, 3, 227–235.

    Article  Google Scholar 

  12. [12]

    Aoki, N.; Sato, A.; Sasaki, H.; Litwinowicz, A. A.; Seong, G.; Aida, T.; Hojo, D.; Takami, S.; Adschiri, T. Kinetics study to identify reaction-controlled conditions for supercritical hydrothermal nanoparticle synthesis with flow-type reactors. J. Supercrit. Fluids. 2016, 110, 161–166.

    Article  Google Scholar 

  13. [13]

    Byrappa, K.; Ohara, S.; Adschiri, T. Nanoparticles synthesis using supercritical fluid technology—Towards biomedical applications. Adv. Drug Deliv. Rev. 2008, 60, 299–327.

    Article  Google Scholar 

  14. [14]

    Aksomaityte, G.; Poliakoff, M.; Lester, E. The production and formulation of silver nanoparticles using continuous hydrothermal synthesis. Chem. Eng. Sci. 2013, 85, 2–10.

    Article  Google Scholar 

  15. [15]

    Nugroho, A.; Yoon, D.; Chung, K. Y.; Kim, J. Synthesis of Li4Ti5O12/carbon nanocomposites in supercritical methanol for anode in Li-ion batteries: Effect of surface modifiers. J. Supercrit. Fluids. 2015, 101, 72–80.

    Article  Google Scholar 

  16. [16]

    Dunne, P. W.; Munn, A. S.; Starkey, C. L.; Lester, E. H. The sequential continuous-flow hydrothermal synthesis of molybdenum disulphide. Chem. Commun. 2015, 51, 4048–4050.

    Article  Google Scholar 

  17. [17]

    Dunne, P. W.; Starkey, C. L.; Gimeno-Fabra, M.; Lester, E. H. The rapid size- and shape-controlled continuous hydrothermal synthesis of metal sulphide nanomaterials. Nanoscale 2014, 6, 2406–2418.

    Article  Google Scholar 

  18. [18]

    Adschiri, T.; Takami, S.; Arita, T.; Hojo, D.; Minami, K.; Aoki, N.; Togashi, T. Supercritical hydrothermal synthesis. In Handbook of Advanced Ceramics, 2nd ed.; Somiya, S., Ed.; Academic Press: Oxford, 2013; pp 949–978.

    Chapter  Google Scholar 

  19. [19]

    Wang, Q.; Tang, S. V. T.; Lester, E.; O’Hare, D. Synthesis of ultrafine layered double hydroxide (LDHs) nanoplates using a continuous-flow hydrothermal reactor. Nanoscale 2013, 5, 114–117.

    Article  Google Scholar 

  20. [20]

    Chaudhry, A. A.; Haque, S.; Kellici, S.; Boldrin, P.; Rehman, I.; Khalid, F. A.; Darr, J. A. Instant nano-hydroxyapatite: A continuous and rapid hydrothermal synthesis. Chem. Commun. 2006, 2286–2288.

    Google Scholar 

  21. [21]

    Giroire, B.; Marre, S.; Garcia, A.; Cardinal, T.; Aymonier, C. Continuous supercritical route for quantum-confined GaN nanoparticles. React. Chem. Eng. 2016, 1, 151–155.

    Article  Google Scholar 

  22. [22]

    Gimeno-Fabra, M.; Munn, A. S.; Stevens, L. A.; Drage, T. C.; Grant, D. M.; Kashtiban, R. J.; Sloan, J.; Lester, E.; Walton, R. I. Instant MOFs: Continuous synthesis of metal-organic frameworks by rapid solvent mixing. Chem. Commun. 2012, 48, 10642–10644.

    Article  Google Scholar 

  23. [23]

    Nugroho, A.; Veriansyah, B.; Kim, S. K.; Lee, B. G.; Kim, J.; Lee, Y. W. Continuous synthesis of surface-modified nanoparticles in supercritical methanol: A facile approach to control dispersibility. Chem. Eng. J. 2012, 193–194, 146–153.

    Article  Google Scholar 

  24. [24]

    Munn, A. S.; Dunne, P. W.; Tang, S. V. Y.; Lester, E. H. Large-scale continuous hydrothermal production and activation of ZIF-8. Chem. Commun. 2015, 51, 12811–12814.

    Article  Google Scholar 

  25. [25]

    Seong, G.; Adschiri, T. The reductive supercritical hydrothermal process, a novel synthesis method for cobalt nanoparticles: Synthesis and investigation on the reaction mechanism. Dalton Trans. 2014, 43, 10778–10786.

    Article  Google Scholar 

  26. [26]

    Arita, T.; Hitaka, H.; Minami, K.; Naka, T.; Adschiri, T. Synthesis of iron nanoparticle: Challenge to determine the limit of hydrogen reduction in supercritical water. J. Supercrit. Fluids. 2011, 57, 183–189.

    Article  Google Scholar 

  27. [27]

    Seong, G.; Takami, S.; Arita, T.; Minami, K.; Hojo, D.; Yavari, A. R.; Adschiri, T. Supercritical hydrothermal synthesis of metallic cobalt nanoparticles and its thermodynamic analysis. J. Supercrit. Fluids. 2011, 60, 113–120.

    Article  Google Scholar 

  28. [28]

    Blood, P. J.; Denyer, J. P.; Azzopardi, B. J.; Poliakoff, M.; Lester, E. A versatile flow visualisation technique for quantifying mixing in a binary system: Application to continuous supercritical water hydrothermal synthesis (SWHS). Chem. Eng. Sci. 2004, 59, 2853–2861.

    Article  Google Scholar 

  29. [29]

    Sugioka, K.; Ozawa, K.; Kubo, M.; Tsukada, T.; Takami, S.; Adschiri, T.; Sugimoto, K.; Takenaka, N.; Saito, Y. Relationship between size distribution of synthesized nanoparticles and flow and thermal fields in a flow-type reactor for supercritical hydrothermal synthesis. J. Supercrit. Fluids. 2016, 109, 43–50.

    Article  Google Scholar 

  30. [30]

    Dimotakis, P. E. Turbulent mixing. Annu. Rev. Fluid Mech. 2005, 37, 329–356.

    Article  Google Scholar 

  31. [31]

    Becker, J.; Hald, P.; Bremholm, M.; Pedersen, J. S.; Chevallier, J.; Iversen, S. B.; Iversen, B. B. Critical size of crystalline ZrO2 nanoparticles synthesized in near- and supercritical water and supercritical isopropyl alcohol. ACS Nano 2008, 2, 1058–1068.

    Article  Google Scholar 

  32. [32]

    Cabañas, A.; Darr, J. A.; Lester, E.; Poliakoff, M. Continuous hydrothermal synthesis of inorganic materials in a near-critical water flow reactor; the one-step synthesis of nano-particulate Ce1‒x ZrxO2 (x = 0–1) solid solutions. J. Mater. Chem. 2001, 11, 561–568.

    Article  Google Scholar 

  33. [33]

    Lim, J. M.; Swami, A.; Gilson, L. M.; Chopra, S.; Choi, S.; Wu, J.; Langer, R.; Karnik, R.; Farokhzad, O. C. Ultra-high throughput synthesis of nanoparticles with homogeneous size distribution using a coaxial turbulent jet mixer. ACS Nano 2014, 8, 6056–6065.

    Article  Google Scholar 

  34. [34]

    Lester, E.; Blood, P. J.; Denyer, J. P.; Azzopardi, B. J.; Li, J.; Poliakoff, M. Impact of reactor geometry on continuous hydrothermal synthesis mixing. Mater. Res. Innov. 2010, 14, 19–26.

    Article  Google Scholar 

  35. [35]

    Sierra-Pallares, J.; Alonso, E.; Montequi, I.; Cocero, M. J. Particle diameter prediction in supercritical nanoparticle synthesis using three-dimensional CFD simulations. Validation for anatase titanium dioxide production. Chem. Eng. Sci. 2009, 64, 3051–3059.

    Article  Google Scholar 

  36. [36]

    Levenspiel, O. Tracer Technology: Modeling the Flow of Fluids; Springer: New York, 2012.

    Book  Google Scholar 

  37. [37]

    Sierra-Pallares, J.; Marchisio, D. L.; Alonso, E.; Parra-Santos, M. T.; Castro, F.; Cocero, M. J. Quantification of mixing efficiency in turbulent supercritical water hydrothermal reactors. Chem. Eng. Sci. 2011, 66, 1576–1589.

    Article  Google Scholar 

  38. [38]

    Cabanas, A.; Darr, J. A.; Lester, E.; Poliakoff, M. A continuous and clean one-step synthesis of nano-particulate Ce1‒x ZrxO2 solid solutions in near-critical water. Chem. Commun. 2000, 901–902.

    Google Scholar 

  39. [39]

    Fogler, H. S. Essentials of Chemical Reaction Engineering; Pearson Education: Boston, 2010.

    Google Scholar 

  40. [40]

    Aizawa, T.; Masuda, Y.; Minami, K.; Kanakubo, M.; Nanjo, H.; Smith, R. L. Direct observation of channel-tee mixing of high-temperature and high-pressure water. J. Supercrit. Fluids. 2007, 43, 222–227.

    Article  Google Scholar 

  41. [41]

    Liu, Y.; Fox, R. O. CFD predictions for chemical processing in a confined impinging-jets reactor. AIChE J. 2006, 52, 731–744.

    Article  Google Scholar 

  42. [42]

    Danckwerts, P. V. The definition and measurement of some characteristics of mixtures. Appl. Sci. Res. A 1952, 3, 279–296.

    Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Edward Lester.

Electronic supplementary material


Understanding bottom-up continuous hydrothermal synthesis of nanoparticles using empirical measurement and computational simulation

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Sierra-Pallares, J., Huddle, T., García-Serna, J. et al. Understanding bottom-up continuous hydrothermal synthesis of nanoparticles using empirical measurement and computational simulation. Nano Res. 9, 3377–3387 (2016). https://doi.org/10.1007/s12274-016-1215-6

Download citation


  • nanoparticle
  • computational fluid dynamics
  • synthesis
  • supercritical
  • inorganics