Efektivitas Nanokomposit ZnO/N-Doped Carbon Nanodots sebagai Material Fotokatalis dalam Degradasi Metilen Biru di Bawah Radiasi Sinar UV

Abstract

The growth of the textile industry in Indonesia continues to increase every year, which is accompanied by the use of synthetic dyes such as Methylene Blue and accompanied by the disposal of waste directly into water bodies. Therefore, a method is needed to degrade Methylene Blue (MB), namely photodegradation. Photodegradation can be carried out using nanoparticles ZnO, N-Doped Carbon Nanodots (N-CNDs), and nanocomposites ZnO/N-CNDs. This research aims to analyze the effectiveness of MB photodegradation using photocatalyst materials. The stages carried out are the synthesis of N-CNDs from molasses and the addition of urea as a dopant agent using the microwave method, the synthesis of nanoparticles ZnO by sonication for 2 hours, and the synthesis of nanocomposites ZnO/N-CNDs using the sonochemical method, then photodegradation of MB using nanocomposites ZnO/N- CNDs with varying exposure times, namely 30, 60, 90, 120 and 150 minutes. Next, MB degradation was carried out using nanoparticles ZnO photocatalysis materials and N-CNDs under UV light radiation for the irradiation time with the highest % degradation. Characterization was carried out on the photocatalyst material and MB after degradation. The results of this research show that the N-CNDs that have been successfully synthesized have a blue luminescence under a 360 nm UV lamp, from the TEM results they are in the form of dots with an average particles diameter of 3.5 nm, and an absorbance spectrum at 246 nm. The synthesized nanoparticles ZnO produced an average particles size of 64.2 nm and an absorbance spectrum of 380 nm. The nanocomposites ZnO/N-CNDs has an average particles diameter of 5.7 nm, and has an absorbance spectrum at a wavelength of 281 nm. The results of MB degradation analysis using nanocomposites ZnO/N-CNDs under UV light radiation for 150 minutes showed the highest degradation effectiveness, namely 79.4%. This proves that the nanocomposites ZnO/N-CNDs photocatalyst material can be applied in MB photodegradation.