Electronic Theses and Dissertation

Biosintesis nanopartikel seng oksida (ZnO) menggunakan ekstrak batang buah naga merah (Hylocereus polyrhizus) dengan prekursor seng asetat dihidrat serta uji aktivitasnya pada penghilangan triklosan dan zat warna Napthol Blue Black (NBB) telah berhasil dilakukan. Senyawa kimia yang terdapat dalam ekstrak air batang buah naga merah seperti terpenoid, steroid, dan fenolik berfungsi sebagai agen pereduksi, stabilisator serta capping agent. Nanopartikel ZnO yang diperoleh dikarakterisasi menggunakan X-Ray Diffraction (XRD), Fourier Transform Infra Red (FTIR), dan Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX). Hasil analisis XRD menunjukkan bahwa seng oksida yang disintesis adalah fase zincite (ZnO) dengan rata-rata ukuran kristal sebesar 79,09 nm. Analisis FTIR menunjukkan nanopartikel ZnO yang disintesis pada suhu kalsinasi 800℃ memiliki karakteristik yang mirip dengan ZnO standard pada bilangan gelombang 511,16 cm-1. Analisis SEM-EDX menunjukkan bahwa nanopartikel ZnO yang disintesis berbentuk bulat, terdistribusi secara merata dan ukuran partikel yang homogen dengan persentase logam Zn serta oksigen sebesar 83,8% dan 16,2%. Hasil uji aktivitas fotokatalis nanopartikel ZnO pada penghilangan triklosan menunjukkan aktivitas yang tinggi dengan persen degradasi triklosan sebesar 51,91% diperoleh setelah diradiasi dengan sinar UV dan 89,36% dengan sinar matahari selama 240 menit. Aktivitas fotokatalitik tersebut diperoleh dengan menggunakan massa fotokatalitik 200 mg dan konsentrasi awal triklosan 10 ppm. Hasil uji aktivitas fotokatalis nanopartikel ZnO pada penghilangan zat warna NBB menunjukkan aktivitas paling tinggi dengan persen degradasi sebesar 98,82% diperoleh pada waktu radiasi dengan sinar UV selama 270 menit. Uji aktivitas fotokatalitik tersebut dilakukan pada kondisi pH larutan zat warna = 2, massa fotokatalis ZnO 250 mg dan konsentrasi awal zat warna 10 ppm.

Kata kunci: nanopartikel ZnO, batang buah naga merah, fotokatalis, triklosan, dan Napthol Blue Black

Biosynthesis of zinc oxide (ZnO) nanoparticles by using red dragon fruit (Hylocereus polyrhizus) stem extract with Zinc acetate as precursor and it’s photocatalytic activity evaluation on the removal of triclosan and Napthol Blue Black (NBB) dye has been successfully performed. Chemical compounds contained in red dragon fruit stem water extract such as terpenoids, steroids, and phenolics act as reducing agent, stabilizer as well as a capping agent. The synthesized ZnO nanoparticles were characterized using X-Ray Diffraction (XRD), Spectroscopy Fourier Transform Infra Red (FTIR), and Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX). The XRD pattern showed that the synthesized zinc oxide was in the zincite (ZnO) phase with an average crystallite size of 79.09 nm. Spectroscopy FTIR analysis showed that the synthesized ZnO nanoparticles at a calcination temperature of 800℃ had similar characteristics with ZnO standard at a wave number of 511.16 cm-1. SEM-EDX analysis showed that the synthesized ZnO nanoparticles were spherical in shape, evenly distributed with homogeneous particles size and with the percentages of zinc and oxygen are 83.8% and 16.2%. The results of photocatalytic activity test of ZnO nanoparticles on the removal of triclosan showed that the highest degradation percentage of triclosan 51,91% was obtained after irradiated under UV and 89,36% after irradiated under sunlight for 240 minutes. These photocatalytic activities were obtained by using 200 mg ZnO nanoparticles and the initial concentration of triclosan was 10 ppm. The results of photocatalytic activity test on the removal of NBB dye showed that the highest degradation percentage 98,82% was obtained after irradiated under UV light for 270 minutes. The photocatalytic activity evaluation was carried out at the initial pH of NBB was 2, mass of ZnO nanoparticles 250 mg, and initial concentration of dye 10 ppm. Keywords: ZnO nanoparticles, red dragon fruit stem, photocatalyst, triclosan, and Napthol Blue Black