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Abstrak :
Penelitian ini telah berhasil mengembangkan metode green synthesis untuk mensintesis nanopartikel Au, SiO2, Al2O3, SiO2/Al2O3, dan SiO2/Al2O3 termodifikasi nanopartikel Au menggunakan ekstrak daun mimba Azadirachta indica yang berperan sebagai agen pereduksi, capping agent, dan sumber basa lemah. Spektrofotometer UV-Visible dan FT-IR digunakan untuk mengkarakterisasi nanopartikel Au, SiO2, Al2O3, SiO2/Al2O3, dan SiO2/Al2O3 termodifikasi nanopartikel Au. Karakterisasi menggunakan UV-Visible menunjukkan adanya nanopartikel Au pada ?maks 533-537 nm. Aktivitas katalitik dari SiO2/Al2O3 termodifikasi nanopartikel Au diamati dalam reaksi reduksi 4-Nitrofenol oleh NaBH4. Hasil menunjukkan bahwa aktivitas katalitik dari SiO2/Al2O3 termodifikasi nanopartikel Au lebih baik dibandingkan SiO2/Al2O3. ......This study successfully developed green synthesis method for synthesis of Au nanoparticles, SiO2, Al2O3, SiO2 Al2O3, and Au modified SiO2 Al2O3 using mimba leaves Azadirachta indica as reducing agent, capping agent, dan a base source. UV Visible Spectroscopy and FT IR were used to characterize Au nanoparticles, SiO2, Al2O3, SiO2 Al2O3, dan Au modified SiO2 Al2O3. UV Visible characterization showed appearance of Au nanoparticles at 533 537 nm. Catalytic activity of Au modified SiO2 Al2O3 was studied in 4 Nitrophenol reduction by NaBH4. The study showed that catalytic activity of Au modified SiO2 Al2O3 better than SiO2 Al2O3.

Abstrak :
[ABSTRAK
Konversi bentuk nanopartikel perak (AgNP) melalui pemanasan dan fotoinduksi terjadi dengan kehadiran sitrat sebagai capping agent dan polivinilpirolidone (PVP) sebagai stabilisator. Awalnya, assintesis nanoprisma perak (AgNP-Biru) dipanaskan selama 30 menit hingga terbentuk nanodisk perak (AgNP-Kuning). Selanjutnya, di bawah penyinaran lampu natrium nanoprisma perak(AgNP-Iradiasi) kembali terbentuk dengan ukuran yang lebih besar. Spektrofotometer UV-Vis dan transmission electron microscopy (TEM) digunakan untuk investigasi pertumbuhan dan konversi bentuk AgNP. Hasil penelitian menunjukkan bahwa parameter kisi AgNP-orange (4.0716 Å) lebih kecil dari AgNP-Iradiasi (4.3134 Å). Hal tersebut mengindikasikan terjadinya rearrangement atom perak pada permukaan AgNP. AgNP dengan bentuk bulat dan triangular diuji akivitas katalitiknya sebagai katalis homogen dan heterogen untuk reduksi 4-nitrofenol. Sebagai katalis heterogen, AgNP diimobilisasi dalam karbon aktif dan dikarakterisasi menggunakan SEM-EDX. Aktivitas katalitik AgNP-Iradiasi lebih aktif daripada AgNP-Orange. Konstanta kinetika reaksi pseudo orde satu reduksi 4-NP dengan NaBH4 adalah 0.2178 s-1 (katalis homogen) dan 0.2225 s-1 (katalis heterogen).

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ABSTRACT
Heated and Photoinduced shape conversion of silver nanoparticles (AgNPs) were occurred in the presence of citrate as capping agent and polyvinylpyrrolidone (PVP) as additional stabilizer. First, the as-synthesized silver nanoprism (AgNP-Blue) were heated to transformed into silver nanodisks (AgNP-Orange) with time. Subsequently, under light irradiation (sodium lamp), an increasing fraction of silver nanoprism (AgNP-Irradiation) develop. The UV-Vis spectrophotometer and transmission electron microscopy (TEM) were adopted to investigate the growth and shape conversion of AgNPs. The result show that the lattice constant of AgNP-Orange converted by heating (4.0716 Å) less than AgNP-Irradiarion (4.3134 Å), which was possibly achieved through rearrangement of silver atoms on the surface of AgNPs. Both silver nanodisk and nanoprism were tested as homogenous and heterogeneous catalyst for reduction of 4-nitrophenol (4-NP). AgNPs supported on activated carbon were synthesized as heterogen catalyst and characterized by SEM-EDX. For catalytic application, AgNP-Irradiation were more actived than AgNP-orange. The kinetic constants of pseudo first orde reaction of reduction 4-NP with NaBH4 are 0.2178 s-1 for homogeneous and 0.2225 s-1 for heterogeneous catalyst, Heated and Photoinduced shape conversion of silver nanoparticles (AgNPs) were occurred in the presence of citrate as capping agent and polyvinylpyrrolidone (PVP) as additional stabilizer. First, the as-synthesized silver nanoprism (AgNP-Blue) were heated to transformed into silver nanodisks (AgNP-Orange) with time. Subsequently, under light irradiation (sodium lamp), an increasing fraction of silver nanoprism (AgNP-Irradiation) develop. The UV-Vis spectrophotometer and transmission electron microscopy (TEM) were adopted to investigate the growth and shape conversion of AgNPs. The result show that the lattice constant of AgNP-Orange converted by heating (4.0716 Å) less than AgNP-Irradiarion (4.3134 Å), which was possibly achieved through rearrangement of silver atoms on the surface of AgNPs. Both silver nanodisk and nanoprism were tested as homogenous and heterogeneous catalyst for reduction of 4-nitrophenol (4-NP). AgNPs supported on activated carbon were synthesized as heterogen catalyst and characterized by SEM-EDX. For catalytic application, AgNP-Irradiation were more actived than AgNP-orange. The kinetic constants of pseudo first orde reaction of reduction 4-NP with NaBH4 are 0.2178 s-1 for homogeneous and 0.2225 s-1 for heterogeneous catalyst]

Abstrak :
Metabolit sekunder pada tanaman memiliki peran penting dalam sintesis nanopartikel. Senyawa yang terkandung pada tanaman dapat menggantikan peran dari stabilizersdan sumber basa dari bahan kimia berbahaya dan beracun, salah satu yang memiliki potensi, yaitu tanaman adas Foeniculum vulgare . Pada bagian batang dari tanaman adas, mengadung senyawa alkaloid yang digunakan sebagai sumber basa untuk sintesis logam oksida. Pada penelitian ini sintesis nanopartikel besi dan vanadium dalam bentuk oksida FeVO4 menggunakan ekstrak batang tanaman adas. Hasil sintesis nanopartikel FeVO4 dianalisis menggunakan spektrofotometer UV-Visible, spektrofotometer Fourier Transform Infra Red FTIR , Transmission Electron Microscopy TEM , Scanning Electron Microscope-Energy Dispersive X-Ray SEM-EDX , X-ray Diffraction XRD , dan Particle Size Analyzer PSA . Kemudian nanopartikel FeVO4dilakukan pengujian kinerja katalis dalam reaksi reduksi 4-nitrofenol. Hasil analisis serapan spektrofotometer UV-Vis, nanopartikel FeVO4memberikan serapan maksimum pada panjang gelombong 441 nm. Karakterisasi spektofotometer FTIR menunjukkan adanya vibrasi logam dengan oksigen pada daerah fingerprint. Pada bilangan gelombang 920-991 cm-1 menunjukkan adanya vibrasi V-O, sedangkan pada 680-890 cm-1 merupakan vibrasi dari V-O-Fe, dan pada kisaran 520 cm-1 menunjukkan adanya vibrasi deformasi V-O-V yang bercampur dengan moderegangan Fe-O. Pola XRD dari FeVO4 menunjukkan puncak difraksi 2theta di 27,64o dan 28,66o dengan struktur kristal anorthic dan space group P-1. Hasil ukuran partikel FeVO4 dengan menggunakan PSA memberikan ukuran sebesar 45 nm. Kinerja katalis nanopartikel FeVO4 terhadap reaksi reduksi 4-nitrofenol dengan pereduktor NaBH4 menunjukkan bahwa persen reduksi dengan berat optimum katalis 5,0 mg pada 20,0x10-5 M 4-nitrofenol sebesar 84,22 4-nitrofenol selama 50 menit. Nilai konstanta laju dari reaksi reduksi 4-nitrofenol sebesar 5,71x10-2 menit-1. ......Secondary metabolites in plants have an important role in nanoparticle synthesis. The compounds contained in the plant can replace the role of stabilizers and bases sources of hazardous and toxic chemicals, one of which has the potential is the fennel plant Foeniculum vulgare . In the fennel plant stems are containing alkaloid compound, it used as the base source for the synthesis of metal oxide. In this research, synthesis of iron vanadate nanoparticles FeVO4 NPs using extract of fennel plant stems. Synthesis of FeVO4 NPs was analyzed using UV Visible spectrophotometer, Fourier Transform Infra Red FTIR spectrophotometer, Transmission Electron Microscopy TEM , Scanning Electron Microscope Energy Dispersive X Ray SEM EDX , X ray Diffraction XRD and Particle Size Analyzer PSA . Then FeVO4NPs were used for catalyst performance in a reduction reaction of 4 nitrophenol.The results show absorbance analysis of UV Vis spectrophotometer, FeVO4 NPs gave maximum absorbance at 441 nm. Characterization of FTIR spectrophotometer shows the presence of metal oxygen vibrations in the fingerprint region. In the wavenumber of 920 991 cm 1are indicating the presence of vibration V O, while at 680 890 cm 1 is a vibration of V O Fe, and in the range of 520 cm 1 shows the vibration of deformation V O V mixed with Fe O stretching mode. The XRD pattern of FeVO4 NPs shows diffraction peaks 2theta at 27.64o and 28.66o with the anorthic crystal structure and the P 1 space group. The result of FeVO4 particle size using PSA gives a size of 45 nm.The catalyst activity of FeVO4 nanoparticles in the 4 nitrophenol reduction reaction with the NaBH4 reductor agent showed that the percent reduction with the optimum weight of 5.0 mg catalyst at 20.0x10 5 M 4 nitrophenol was 84.22 for 50 minutes. The rate constant value of reduction reaction of 4 nitrophenol was 5.71x10 2min 1.