Optimasi Suhu Kalsinasi Terhadap Sintesis Nanostruktur Zno Sebagai Fotokatalis Dengan Memanfaatkan Buah Nanas Sebagai Pengkelat

Abstract

Abstrak
ZnO telah disintesis dengan metode sol-gel menggunakan pengkelat dari ekstrak buah nanas sebagai solusi agar
dapat mengurangi penggunaan zat kimia. Buah nanas yang digunakan yaitu nanas madu dan nanas batu yang
memiliki kandungan kadar gula total berbeda. Pada nanostruktur ZnO yang menggunakan pengkelat nanas madu
disintesis pada suhu kalsinasi 500, 600, 700, 800, dan 900ËšC. Nanostruktur ZnO yang menggunakan pengkelat
nanas batu berhasil disintesis pada suhu kalsinasi 700 dan 800ËšC. Dalam eksperimen ini dipelajari efek suhu
kalsinasi terhadap hasil nanostruktur ZnO serta pengaruhnya saat diaplikasikan sebagai fotokatalis untuk
mendegradasi methylene blue. Hasil karakterisasi morfologi dengan SEM sampel menggunakan pengkelat
nanas madu di suhu kalsinasi 800˚C diketahui bahwa ukuran partikel berada pada rentang 0,540 – 3,614 μm
dengan rata-rata 1,858 μm, hasil yang masih besar diperkirakan terjadi karena adanya aglomerasi. Karakterisasi
terhadap sifat kristal dengan menggunakan XRD di dapatkan ukuran kristal pada sampel menggunakan
pengkelat nanas madu di suhu kalsinasi 800ËšC dengan rata-rata 35,10 nm sementara pengkelat nanas madu di
suhu kalsinasi 700ËšC, ukuran kristalit yaitu dengan rata-rata 30.90 nm. Kedua sampel yang dikarakterisasi sifat
kristalnya dengan menggunakan XRD memiliki struktur kristal wurtzite berbentuk heksagonal yang berukuran a
= 3,25 x 10
−10
m dan c = 5,21 x 10
−10
m.
Kata kunci : ZnO, green synthesis, metode sol-gel, degradasi metilen biru, suhu kalsinasi

Abstract
ZnO has been synthesized by the sol-gel method with chelate from pineapple (Ananas comosus (L.)) extract, as
a solution to reduce the chemical substances. Pineapple extract is used as a chelate because it has high total
sugar content. ZnO nanostructure that has been synthesized with cayenne pineapple chelate was synthesized at
calcination temperatures of 500, 600, 700, 800 and 900 ËšC, whereas ZnO nanostructure that has been
synthesized with queen pineapple chelate was synthesized at calcination temperatures of 700 and 800 ËšC. The
morphology of ZnO nanostructure has been checked by Scanning Electron Microscopy (SEM). ZnO
nanostructure that has been synthesized with cayenne pineapple chelate at calcination temperature of 800 ËšC
showed particle size average of 1,858 μm, these result was still too large and occurred due to agglomeration.
The crystallite structure of calcined powders were analyzed using XRD. The average size of zno nanostructure
crystallite was synthesized with cayenne pineapple chelate at 800 ËšC calcination temperature, which was 35,10
nm while at calcination temperature 700 ËšC the average size of crystallite was 30.90 nm. The diffraction peaks
can be indexed as hexagonal wurtzite structure of ZnO (a = 3,25 x 10
−10
m, c = 5,21 x 10
−10
m) and diffraction
data were in good agreement with the JCPDS card for ZnO (JCPDS 36-1451). The photocatalytic activity of
ZnO catalysts obtained by modified sol-gel method at different calcination was valuated for the photo
degradation of methylene blue under UV light. The most effective degradation occurred in Zno nanostructure
which was synthesized with cayenne pineapple as chelate at 700 ËšC calcination temperature during UV
irradiation for 240 minutes, the degradation rate was 55,87% at a concentration of 10 ppm MB solution.
Keywords: ZnO, green synthesis, sol-gel method, degradation of methylene blue, calcination temperature