One-pot synthesis of metal-free, yellow-emitting phosphor with organic single crystal as a matrix

• Published in: Dyes and pigments 2021-09, Vol.193, p.109518, Article 109518
• Main Authors: Zhou, Shengju, Lu, Dandan, Sun, Xiaofeng, Yin, Keyang, Zhang, Geping, Chen, Mengjun, Li, Hongguang
• Format: Article
• Language: English
• Subjects: Light-emitting diode; Metal-free; Phosphor; Photoluminescent; Single crystal
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/j.dyepig.2021.109518

In recent years, there is a rapid growth on the research of metal-free phosphor. A typical example is blend of photoluminescent carbon nanomaterials with a matrix. Normally, the C dots were prepared first, which were then mixed with the matrix. A drawback of this strategy is that multiple steps have to be involved, which is time consuming. In this work, we show that by simply heating a readily-available small organic molecule (phthalic acid) in a high-boiling solvent with reactive group (formamide), ready-to-use and metal-free phosphor can be produced in high yields (over 70%). The phosphor contains single crystals of phthalic anhydride with photoluminescent species adsorbed on the surfaces, which shows yellow emission in solid state with a fluorescence quantum yield (Φ) of 28.53%. The phosphor can be directly used to prepare light-emitting diodes (LEDs), which results in a yellow LED on the UV chip and a white LED on the blue-emitting chip. Single crystals of small organic molecules with carbon dots adsorbed on the surface have been prepared. The hybrid material shows yellow emission, which can be used as metal-free phosphor for white-light-emitting diodes. [Display omitted] •Metal-free phosphor can be readily prepared in one-step with high yield.•The phosphor can be directly used to prepare LEDs. On the blue-emitting LED chip, a white LED was obtained.•The as-prepared crystals exhibit strong emission in both solid and colloidal state.