Green Synthesis of Gold Nanoparticles using Peronema canescens Leaves Extract and Their Catalytic Performance for Dyes and Nitro Compounds

The most interesting and well-known research in the field of gold nanomaterials synthesis is the use of "green chemistry" to prepare gold nanoparticles (AuNPs). In this study, Peronema canescens leaf extract was used as the synthesis medium to successfully produce AuNPs in a way that was cheap, quick, and good for the environment. A UV-visible spectrophotometer, particle size analysis (PSA), and transmission electron microscopy (TEM) were used to find out more about the AuNPs that were prepared. The UV-visible spectrophotometer showed a surface plasmon resonance peak at 532 nm, which proves that AuNPs exist in the solution. TEM and PSA both showed that the AuNPs were mostly spherical and had an average diameter of 14.9 nm, respectively. In the presence of NaBH4, the AuNPs were found to speed up the reduction of rhodamine B (RhB), metanil yellow (MY), and 4-nitrophenol (4-NP). The results show that the AuNPs that were prepared in a new way worked very well and could be used in catalysis

Easy Handling Preparation of Cubic Sulfur in Aqueous Extract of Sapindus rarak rinds

The aqueous extract of Sapindus rarak (S. rarak) was produced by heating its rinds in demineralized water at 80 °C. The main experiment was conducted at room temperature by mixing a solution of sodium thiosulfate with the extract obtained previously. After adding dilute hydrochloric acid (10%), fine granules gradually formed in the solution and precipitated when the reaction was stopped and allowed to stand for 24 h. The analysis results showed the consistency of the X-ray diffraction (XRD) peak of the obtained material with sulfur standards. When looked at the surface using scanning electron microscopy (SEM), sulfur was found to be cube-shaped. The formation of cuboidal elemental sulfur possibly occurs due to the covering of thiosulfate ions and elemental sulfur during and after the reaction. Organic compounds were found covering sulfur through elemental and functional group analyses using energy-dispersive X-ray (EDX) and Fourier-transform infrared (FTIR) spectroscopy, respectivel

Reduction of 4-nitrophenol Mediated by Silver Nanoparticles Synthesized using Aqueous Leaf Extract of Peronema canescens

In this study, we developed an alternative of 4-nitrophenol reduction mediated by silver nanoparticles (AgNPs) which was synthesized using aqueous extract of the Peronema canescens leaf through an eco-friendly approach. The reducing 4-nitrophenol to 4-aminophenol mediated by AgNPS in the presence of sodium borohydride as a hydrogen source proceeded rapidly at room temperature without any additional treatments. The AgNPS synthesis was simple and was carried out under mild conditions. Ultraviolet–visible spectroscopy was performed to examine the properties of the obtained AgNPs, which displayed an absorption peak at 431 nm. A transmission electron microscopy analysis revealed that the AgNPs were spherical in shape and had an average particle size of 19 nm as determined by particle size analysis. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Preliminary Synthesis of Calcium Silicates using Oil Palm Leaves and Eggshells.

A new synthetic procedure is described for the synthesis of calcium silicate derivatives, using natural resources such as eggshell (ES) for calcium and oil palm leaves (OPL) for silica, which do not require prepurification. The reaction is performed by directly converting two weight ratio of the precursors, ES:3OPL and ES:6OPL, to dried-powder form by heat treatment at 900 °C for two hours. The results demonstrate that the concentration of the precursors has an effect on the morphology and crystallinity of the calcium silicate derivatives, mainly Ca2SiO4 and CaSiO3. X-ray diffraction results reveal that the reaction product obtained using a 1:3 ratio is quite pure, and mainly consisted of calcium silicate in the form of Ca2SiO4. The CaSiO3 was also identified in ES:6OPL, together with a small amount of excess non-reacted crystalline silica. Furthermore, a scanning electron microscopy analysis shows that both reaction products have a coarse surface. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

EKSTRAK BUNGA TAPAK KUDA (Ipomoea pescaprae L. Sweet) SEBAGAI MEDIUM SINTESIS NANOPARTIKEL EMAS

Pada penelitian ini, nanopartikel emas disiapkan melalui pendekatan green synthesis menggunakan ekstrak air bunga tapak kuda (Ipomoea pescaprae L. Sweet). Nanopartikel emas yang dihasilkan dianalisis menggunakan spektrofotometer UV-Vis, Mikroskop Leica, Particle Size Analyzer (PSA), Spektrofotometer Fourier Transform Infra-Red (FTIR) dan X-ray Difractometer (XRD). Hasil pengukuran  PSA menunjukkan ukuran partikel terbaik, diperoleh dengan menggunakan perbandingan volume 1 mL  larutan HAuCl4 dengan 9 mL ekstrak yang menghasilkan partikel dengan ukuran rata-rata 16,3 nm. Hasil penampakan dengan mikroskop cahaya, memperlihatkan partikel berbentuk bulat. Pergeseran bilangan gelombang pada spektrum infra-merah menunjukkan adanya interaksi antara metabolit sekunder dari ekstrak dengan material emas. Analisis XRD menunjukkan bahwa nanopartikel emas telah dapat dihasilkan dari kondisi reaksi ini

Fabrication of Silver-Silica Composite using the Carbo-thermal Degradation of Oil Palm Leaves for the Reduction of p-nitrophenol

Oil palm leaves are natural sources of bio-silica. In situ carbothermal degradation was conducted at 600°C using silver nitrate as a metallic silver (Ag) precursor and oil palm leaves as a silica (SiO2) source. X-ray diffraction of the solid product (Ag@OPLA600) revealed the presence of Ag and SiO2 from the oil palm leaves. Fourier transform infrared spectroscopy showed an absorbance consistent with the presence of SiO2. Scanning electron microscopy revealed a solid surface with cavities. Ag@OPLA600 was used as a heterogeneous mediator to reduce p-nitrophenol to p-aminophenol within 15 minutes. This work provides a new approach for the utilization of sustainable natural resources as a metal Ag supporting material to produce a mediator for the conversion of p-nitrophenol to p-aminophenol in a simple manner

SINTESIS DAN KARAKTERISASI MEMBRAN BIONANOKOMPOSIT MENGGUNAKAN SELULOSA BAKTERI DARI NIRA AREN (Arenga pinnata Merr) dan AgNO 3

Sintesis membran selululosa bakteri-AgNPs telah dilakukan menggunakan selulosa bakteri dan AgNO sebagai perkusor. Selulosa bakteri dibuat dari Nira Aren (Arenga pinnata Merr) menggunkan Acetobacter xyliunum. AgNPs dibuat dengan cara mereduksi AgNO 3 menggunakan ekstrak kulit kering tanaman Brucea javanica (L) Merr. Membran selulosa dimasukan kedalam laruatn AgNPs untuk mendapatan membran bionanokomposit yang diinginkan. Bionanokomposit dkarakterisasi menggunkan spektrofotometer UV-Vis dan SEM-EDX. Hasil menujukan membran bionanokomposit tidak menunjukan puncak serapan saat dianalisis menggunakan Spktofotometer UV-Vis dan analisis menggunkan SEMEDX menujukan membran bionanokomposit memiliki bebrapa pori. Membran binanokoposit yang didapatkan digunakan untuk katalis untuk oksidasi benzil alkohol. Sayangnya, hasil menujukan tidak memberikan senyawa benzaldehid pada kondisi saat ini.

Removal of Propylparaben in an Aqueous System using Magnetite-Silica Ferrofluids of Hydrophobic Deep Eutectic Solvent

A novel sorbent based on ferrofluid hydrophobic deep eutectic solvent magnetite silica (Fe3O4@SiO2@mSiO2- HDES) was successfully synthesized by adding menthol-fatty acid as carrier liquid onto Fe3O4@SiO2@mSiO2 composite. The crystallinity, morphological, functional group and magnetic properties of the materials were characterized by x-ray diffraction, scanning electron microscopy-EDX, Brunauer–Emmett–Teller, vibrating sample magnetometer, thermogravimetric analysis and Fourier Transform-infrared spectroscopy. The adsorption performance of parabens was evaluated as model water pollutants. The Fe3O4@SiO2@mSiO2-HDES ferrofluid was used as a ferrofluid sorbent of parabens prior to spectrophotometry UV-Vis. The effect of several contribution parameters was optimized including ferrofluid volume, pH, stirring time and ionic strength. Under the optimum conditions, a combination of Fe3O4@SiO2@mSiO2-menthol/palmitic acid was achieved as the best ferrofluid with % removal values ranging from 81.00% to 98.62%. The ferrofluid Fe3O4@SiO2@mSiO2-HDES demonstrated high efficiency for the adsorption paraben in the water system which suggests a great potential alternative method for the adsorption of water contaminants in the aquatic system

Reduction of 4-nitrophenol Mediated by Silver Nanoparticles Synthesized using Aqueous Leaf Extract of Peronema canescens

In this study, we developed an alternative of 4-nitrophenol reduction mediated by silver nanoparticles (AgNPs) which was synthesized using aqueous extract of the Peronema canescens leaf through an eco-friendly approach. The reducing 4-nitrophenol to 4-aminophenol mediated by AgNPS in the presence of sodium borohydride as a hydrogen source proceeded rapidly at room temperature without any additional treatments. The AgNPS synthesis was simple and was carried out under mild conditions. Ultraviolet–visible spectroscopy was performed to examine the properties of the obtained AgNPs, which displayed an absorption peak at 431 nm. A transmission electron microscopy analysis revealed that the AgNPs were spherical in shape and had an average particle size of 19 nm as determined by particle size analysis. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).