Sintesis dan Karakterisasi Nanokomposit MoS2/N-Doped Carbon Dots Berbasis Cangkang Biji Karet (Hevea brasiliensis) dengan Metode Sonikasi

Abstract

Nitrogen-doped Carbon Dots (N-CDs) are nanoscale materials with high fluorescence intensity and large band gap. Molybdenum disulfide (MoS₂) is a semiconductor with a narrow band gap and high visible light absorption capacity. This study aimed to synthesize and characterize MoS₂/N-CDs nanocomposites using the sonication method. In the first stage, N-CDs were synthesized using rubber seed shells biomass as a precursor and urea as a nitrogen source via the hydrothermal method at 180 °C for 16 hours. The second stage MoS₂/N-CDs nanocomposites were then synthesized by using the sonication method. The results showed that N-CDs were successfully synthesized, as confirmed by the formation of blue fluorescence under UV light and TEM analysis, which showed a spherical morphology with an average particle size distribution of 2.8 nm. FTIR analysis showed the presence of N-H, O-H, C≡C, C-O, C=C, and C-N groups in N-CDs, as well as characteristic Mo–S and S–S vibrations in MoS₂/N-CDs nanocomposites. The photoluminescence (PL) spectrum showed emission peaks at 425 nm for N-CDs and 445 nm for MoS₂/N-CDs nanocomposites. UV-Vis analysis showed absorption peaks for N-CDs at 234 and 312 nm, while MoS₂/N-CDs nanocomposites showed absorption peaks at 347 and 734 nm. Band gap values of 3.06 eV and 2,52 eV were obtained for N-CDs and MoS₂/N-CDs nanocomposites, respectively. SEM-EDX analysis of MoS₂/N-CDs nanocomposites showed a stacked nanosheet morphology composed of Mo, S, C, N, and O elements. Analysis of the MoS₂/N-CDs nanocomposite using a Surface Area Analyzer (SAA) showed a specific surface area of 8.43 m²/g, a total pore volume of 0.03 cm3/g, and an average pore size of 7.17 nm. These results confirm that the MoS₂/N-CDs nanocomposite had been successfully synthesized.