New route to tailor-made diamond nanoparticles holds promise for quantum applications

New route to tailor-made diamond nanoparticles holds promise for quantum applications Stephanie Baum Scientific Editor Robert Egan Associate Editor Nanodiamonds are tiny diamond particles only a few nanometers in size. Because they are chemically highly stable and can host so-called color centers, optically active defects in the crystal lattice, they are considered promising materials for quantum technologies, sensing and biomedical research. Until now, however, it has been difficult to reliably produce nanodiamonds with uniform size, high purity and precisely integrated optical properties. An international research team led by Dr. Yingke Wu and Professor Tanja Weil at the Max Planck Institute for Polymer Research has now developed a new synthesis strategy. Instead of breaking larger diamonds down into smaller particles, the team builds nanodiamonds from the bottom up using molecularly defined nanographene building blocks. Under high pressure and at high temperatures, these flat carbon molecules are directly converted into diamond-like, highly crystalline nanostructures. The research is published in the journal Nature. The key advantage of this bottom-up approach lies in its control at the molecular level. Because the structure, size and composition of the starting molecules are precisely defined, the properties of the resulting nanodiamonds can be controlled much more effectively than with conventional milling or top-down methods. Using this strategy, the team was able to produce particularly small, uniform nanodiamonds measuring around three to four nanometers. Another important aspect is that optically active color centers can be incorporated into the diamond lattice directly during synthesis. By using suitable molecular precursors, silicon- and germanium-based emitters can be generated without the need for subsequent ion implantation, irradiation or further post-treatment. This makes it possible to produce fluorescent nanodiamonds with tailored optical properties in a single synthesis step. "We believe this platform offers a scalable foundation for developing quantum sensors, integrated photonic emitters and programmable diamond-based nanomaterials," says Weil. The new molecular nanodiamonds open up promising opportunities for applications in quantum technology; for example, as stable single-photon sources or nanoscale sensors. They are also of interest for biological and medical research. In the long term, they could serve as robust optical reporters to visualize processes in cells or other biological environments at the smallest scales. Publication details Jiaxu Liang et al, Bottom-Up Synthesis of Molecular Nanodiamond from Nanographene, Nature (2026). DOI: 10.1038/s41586-026-10669-3 Journal information: Nature Key concepts Crystal phenomena0-dimensional systemsCrystalline systemsNanostructuresOptical materials & elementsSample preparationProvided by Max Planck Society