Optimization of Preparation Technology for PET-Based Carbon Dots by Response Surface Method and Its Application.

The preparation of polyethylene terephthalate(PET)-based Carbon Dots (PET-CDs) using one-step hydrothermal method with PET waste, pyromellitic acid (PMA) and ammonia (NH·HO) as precursors is a high-value utilization strategy for PET waste, offering significant application potential. To achieve efficient recycling of PET waste, response surface methodology was adopted for to optimize the precursor ratio during the synthesis of PET-CDs with fluorescence quantum yield (QY) as the key performance indicator. The optimal preparation conditions were determined to be: 1.

Preparation of Carbon Dots from PET Waste by One-step Hydrothermal Method and its Application in Light Blocking Films and LEDs.

An environmentally friendly PET-based Carbon Dots (PET-CDs) with excellent fluorescence properties were prepared with waste PET bottle, pyromellitic acid and ammonia water as raw materials by one-step hydrothermal method. The preparation mechanism of PET-CDs was as follows: PET first underwent ammonolysis reaction to produce terephthalic acid diamide and ethylene glycol, and then dehydrated and carbonized with pyromellitic acid to form PET-CDs. The as-prepared PET-CDs exhibit excitation-independent emission properties in the range from 340 to 440 nm, and the fluorescence quantum yield is as high as 87.