Nanodiamonds made from tiny graphene triangles

Nanodiamonds can host atom-sized light emitters for quantum sensing and imaging, but making nanodiamonds that are small, crystalline and uniform has been difficult. A single-step process for making nanodiamonds only 3–4 nanometres in size uses planar carbon ‘nanographene’ molecules with hydrogen atoms on the edges, and can be adapted to generate fluorescent nanodiamonds. Molecular nanodiamonds with a narrow size distribution of 3 to 4 nanometres can be made on the milligram scale.