Simple, eco-friendly, continuous, and straightforward flame aerosol synthesis of single-phase nanoporous monetite biomaterials

In recent years, monetite (CaHPO₄) has gained broad attention for its potential in different applications, specifically orthopedic and dental applications. This rapid communication reports, for the first time, a one-step continuous synthesis pathway for nanoporous monetite particles, which can also be classified as an eco-friendly method. The method is a flame-based aerosol process; thus, the particles are generated via a gas-phase process. However, it was found that the pathway to single-phase monetite involves reactions between the precursor components already in the liquid phase, which also need to be taken into account. Specifically, the residence time in liquid-phase environment prior to spraying should be considered for synthesizing the single-phase monetite. Consequently, single-phase nanoporous monetite particles (with two different morphologies: spherical and plate-like) were successfully synthesized using only deionized water as the solvent, without the need for surfactants, by optimizing the synthesis parameters and the residence time in the liquid phase.