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.