What do we do?

TiO2 TiO2 Nanoparticles with an average particle size around 10nm and low particle size distribution

Promethean Particles provides a bespoke service to a range of industrial partners. Instead of offering a catalogue of products we work with our customers to develop the material they need. This is because we recognise that every application requires a different product specification to optimise its functionality.

We work with our customers to design a feasibility study that utilises our lab-scale reactors, allowing us to rapidly produce and screen materials. Once the optimal particle specification and formulation has been identified, or if you know what you want, we can offer larger scale manufacturing capabilities.

We recognise that every application of nanoparticles is unique and requires a tailor-made material to achieve optimum results.

That’s why we work with our customers to develop a solution that meets their needs.

Note: All materials are prepared as dispersions in a one step process avoiding agglomeration


Feasibility Studies

Depending on how well our customers understand the material they want and their stage of product development we offer feasibility studies that range from “a quick look see” to a thorough investigation of the optimal particle composition, specification and formulation.

Contact us to discuss your inorganic nanoparticle requirements.


Manufacturing Capabilities

In addition to our lab-scale facilities that provide rapid screening capabilities and gram scale manufacture we also have a pilot-scale facility offering kg quantities of materials. If larger quantities are required we have outsourcing capability.

Pilot scale manufacturing plant


Contact us to discuss your manufacturing needs.



The process provides an elegant solution to nanoparticle production; it is a simple, single-step, continuous process, which uses simple precursors and water as a solvent allowing the production of a diverse range of products.

The reactor, coupled with our knowledge and experience, enables us to develop and manufacture bespoke nanoparticles, tailored to our customer’s requirements by altering a number of reaction variables.


Product Control

By altering the salt solution (precursor) a wide range of materials can be produced, including complex materials such as mixed metal oxides with precisely controlled stoichiometries, simple metal oxides, metals and sulfides.


Control of variables

Hydroxyapatite – Artificial Bone
150nm long and 30nm wide

Control of variables such as temperature, pressure, flow rates and reaction residence time allows fine control of the particle properties such as particle size, size distribution and morphology.

We have shown the ability to control particle size from a few nm to larger than 150 nm, narrow particle size distributions are possible and we have experience of altering the particle morphology from spherical to platelets or rods.

Our experience of working with the reactor means that we understand how these variables affect the particles and can produce the desired properties in a predictable manner.


Relevant Articles

Read more about the process system.

The nozzle reactor in J. Supercritical Fluids – Edward Lester, Paul Blood, Joanne Denyer, Donald Giddings, Barry Azzopardi and Martyn Poliakoff, 2006 Reaction engineering: The supercritical water hydrothermal synthesis of nano-particles The Journal of Supercritical Fluids, 37 (2), 209-214

The mixing problems in other standard reactors – 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)  Chemical Engineering Science 59 (14), July 2004, 2853-2861.