Optimization of high efficiency blue emissive N-, S-doped graphene quantum dots

Tiras K., Soheyli E., Sharifirad Z., Mutlugun E.

OPTICAL MATERIALS, cilt.159, 2025 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 159
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.optmat.2024.116544
  • Dergi Adı: OPTICAL MATERIALS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Applied Science & Technology Source, Chimica, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC
  • Anahtar Kelimeler: Solvothermal, Graphene quantum dots, Blue emission, High emission quantum yield
  • Erciyes Üniversitesi Adresli: Evet

Özet

Graphene quantum dots (GQDs) with bright emission at short wavelengths have attracted much attention due to their importance in various applications such as light-emitting diodes. During or after synthesis, several parameters can significantly improve the optical properties of GQDs. This study presents a facile solvothermal method with low-cost precursors using glutamic acid as the carbon source to realize blue emitting GQDs. The positive effects of urea and 1-octanethiol as nitrogen and sulfur dopants on the photoluminescence quantum yield (PLQY) of the prepared GQDs were demonstrated and optimized. The results confirmed the formation of 2.2 nm nanoparticles with a bright emission around 381 nm with a full width at half maximum of 58 nm and a PLQY approaching 70 %. The decay lifetime of the emission also showed a tri-exponential profile with an average lifetime of 2.4 ns. The simplicity of the preparation method without any post-treatment process, together with a high PLQY of 70 % at short wavelengths, nominates the prepared GQDs for optoelectronics and UV light-driven biological purposes.