CD Tesis

Biosintesis Dan Karakterisasi Lapisan Zno Menggunakan Ekstrak Kulit Citrullus Lanatus Diaplikasikan Sebagai Fotokatalis Pendegradasi Metilen Biru

---

The biosynthesis of ZnO photocatalyst material in the form of thin films is increasingly needed as an environmentally friendly alternative to chemical and physical methods, especially in large-scale water purification processes. The aim of this research is to produce a ZnO-based photocatalyst material in the form of a thin layer through an environmentally friendly method and optimize the surface of the ZnO thin layer by varying the acidity level at the time of synthesis.
Sample preparation was initiated by mixing 0.25 M zinc nitrate hexahydrate (Zn (NO3) 2.6H2O) with watermelon rind extract (50 gr/l) at 80 C with various acidity conditions (pH 6, 8, 10 and 12) until ZnO colloids form. The ZnO thin layer was made by spin-coating the biosynthetic ZnO colloid onto the cleaned glass substrate. ZnO photocatalyst activity was tested in the degradation process of methylene blue (MB) under UV-C irradiation by analyzing the reduction rate of the absorption peak characteristic of MB. The optical properties, structure, morphology, elemental composition and functional groups contained in the sample were characterized using UV-Vis spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX) and Fourier Transform Infra Red (FTIR).
Sample prepared at pH of 12 (TF12) have the highest percentage degradation value and the largest reaction constant value where the percentage value of decolorization after 150 minutes is 94.61% and the reaction constant is 0.01935 min-1. The optical absorption peak of the TF12 sample has the highest optical absorption at a wavelength range of 300 to 370 nm with the lowest bandgap energy of 3.088 eV. The X-ray diffraction pattern of all samples shows a hexagonal wurtzite structure with the highest peak at an angle of the (101) hkl at 2θ = 36.37 °. The surface morphology of the ZnO layer is spherical in shape with the smallest size of 78.72 nm. The acidity level affects the purity level of the ZnO thin film, where the TF6 sample still contains impurities such as Silicon, Calcium and Magnesium, while the TF12 sample is free of impurities. Based on the FTIR spectrum, all samples show the presence of Zn-O bonds at wave number 343.68 cm-1 - 573.90 cm-1 and the dominant -OH functional group is present in the TF12 sample. Based on the results of this study, photocatalytic efficiency and physical properties of ZnO film has a strong correlation with the acidity level (pH) in the synthesis process. It can be concluded that the ZnO thin layer prepared using the watermelon peel extract shows good photocatalyst activity and is effective in photodegrading methylene blue so that it could be developed for the photocatalytic process of water purification.
Keywords: Biosynthesis, Zinc oxide, Citrullus lanatus, Methylene Blue

---

Ketersediaan

Informasi Detail

Judul Seri

-

No. Panggil

10 17. 221 (0003)

Penerbit

Pekanbaru : Universitas Riau – Pascasarjana – Tesis Fisika., 2021

Deskripsi Fisik

xiv, 80 hlm.: ill.: 29 cm

Bahasa

Indonesia

ISBN/ISSN

-

Klasifikasi

10 17. 221 (0003)

Tipe Isi

-

Tipe Media

-

Tipe Pembawa

-

Edisi

-

Subjek

FISIKA

Info Detail Spesifik

-

Pernyataan Tanggungjawab

FATAH

Versi lain/terkait

Lampiran Berkas

Komentar

---

Anda harus masuk sebelum memberikan komentar