▎ 摘　　要

Triammonium citrate crystal (TAC) has many applications in food, pharmaceutical, agricultural and other industries. In this work, TAC crystals were synthesized using a new method and with the least use of materials and tools. This crystal has a unique structure and special and new angles and bonds that were identified by crystallography. This crystal was then used to synthesize nitrogen- doped graphene quantum dot (N-GQD) with hydrothermal method. Synthesized N-GQD has particular morphology, fluorescence and viscosity. Compared with other nitrogen compounds necessary for N-GQDs synthesis, ammonia is much more suitable due to its low toxicity and stability. Synthesized TAC and N-GQD were identified by FT-IR, XRD, TGA, EDS, SEM, crystallography and fluorescence.