Efektivitas Carbon Dots dari Limbah Plastik Polyethylene Terephthalate sebagai Fotodegradasi Methylene Blue di Bawah Radiasi Sinar UV

Abstract

The high use of plastic bottles as drinking water packaging results in the production of plastic bottle waste. In general, the materials used to make plastic bottles are made from polyethylene Terephthalate (PET) polymer with a carbon content of 62.5%. This research aims to utilize polyethylene terphthalate plastic bottles to make carbon dots and analyze the effectiveness of carbon dots as a photocatalyst in degrading methylene blue. Synthesis of carbon dots from PET plastic bottles using the hydrothermal method, at 180oC heating for 12 hours. The research results show that carbon dots have been successfully synthesized from PET plastic waste which is confirmed by the results of bluish green luminescence under a 365 nm UV lamp, absorbance peak of 309 nm, carbon dots emission intensity at a wavelength of 372 nm. TEM analysis shows that the carbon dots are round with an average diameter of 4,369 nm, and C=C groups are formed at a wave number of 1640 cm-1 from FTIR analysis. The carbon dots obtained were then applied as a photocatalyst to degrade methylene blue dye with varying exposure times of 1, 3 and 5 hours using 20 watt UV radiation. The results of degradation analysis from UV-Vis data show the highest degradation effectiveness, namely 97,07% with a time of 5 hours. This proves that the carbon dots photocatalyst material can be applied in the photodegradation of methylene blue.