Siregar, Afriana2022-03-142022-03-142021-08wahyu sari yenihttps://repository.unri.ac.id/handle/123456789/10459Synthesis and characterization of ZnO nanoparticles have been successfully carried out using ketapang leaf extract to degrade methylene blue. ZnO nanoparticles were formed through the synthesis of a 0.05 M solution of ZnO(NO3)2 with ketapang leaf extract. The synthesis was carried out using variations in the volume of the ketapang leaf extract and zinc nitrate solution, namely A (1:3), B (1:5) and C (1:7) and then 1 M NaOH was added until each variation showed a pH of 12. The results were characterized using UV-Vis Spectrophotometer resulting in absorbance values of 0.619; 1.196 and 1.095. X-ray diffraction (XRD) characterization of sample B showed that the particle size is in the range of 10.59-23.73 nm with Miller indices of (100); (002); (101); (012) ; (110); (013) and (112). SEM characterization showed the presence of nano-flower morphology with size distribution in the range of 400-494 nm. The degradation activity of methylene blue for absorption test using UV-Vis Spectrophotometer at a concentration of 25 ppm with an optimum time of 6 hours resulted in the degradation efficiency of 29 %, 32,2 % and 36,7 %.enZnO nanoparticlesKetapang leafMethylene BlueUV-VisXRDArticle