Plant-mediated fabrication and surface enhanced raman property of flower-like Au@Pd nanoparticles

The flower-like nanostructures of an Au core and Pd petals with the average size of 47.8 nm were fabricated through the successive reduction of HAuCl4 and Na2PdCl4 at room temperature. During the synthesis, Cacumen Platycladi leaf extract served as weak reductant and capping agent. Characterization techniques such as Energy-dispersive X-ray spectroscopy, UV-Vis spectroscopy, and X-ray diffraction characterizations were employed to confirm that the as-synthesized nanoparticles have the structure of core-shell. The obtained core-shell nanoflowers exhibited good surface enhanced Raman spectroscopic activity with Rhodamine 6G. ? 2014 by the authors

Biogenic flower-shaped Au-Pd nanoparticles: Synthesis, SERS detection and catalysis towards benzyl alcohol oxidation

～40 nm flower-shaped Au-Pd bimetallic nanoparticles were prepared in a facile and eco-friendly way based on the simultaneous bioreduction of HAuCl 4 and Na2PdCl4 with ascorbic acid and Cacumen Platycladi leaf extract at room temperature. Characterization techniques, such as transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction, were employed to confirm that the as-synthesized nanoparticles were alloys. The obtained flower-shaped Au-Pd alloy nanoparticles exhibited an excellent surface enhanced Raman spectroscopic activity with rhodamine 6G and efficient catalytic ability for the oxidation of benzyl alcohol to benzaldehyde. ? 2014 The Royal Society of Chemistry

Biosorption of Ag(I) from aqueous solution by Bacillus licheniformis strain R08

Conference Name:2012 International Conference on Sustainable Energy and Environmental Engineering, ICSEEE 2012. Conference Address: Guangzhou, China. Time:December 29, 2012 - December 30, 2012.Biosorption of heavy metals is an effective technology for the treatment of industrial wastewater. In this paper, Bacillus licheniformis R08 was used as biosorbent for Ag+. The physic-chemical properties of biosorption of silver by Bacillus licheniformis R08 were studied. Experimental parameters, including pH, temperature, biosorption time, initial silver ion concentration and biomass concentration were optimized. Under the optimized conditions, the silver biosorption capacity and biosorption efficiency could reach 73.6mg·g-1 and 73.6%, respectively. Equilibrium isotherms of biosorption by R08 were fitted by Langmuir equation and the theoretical maximum biosorption capacity was 136 mg·g-1. FTIR results showed that-CO-NH and -COO- groups of R08 cell were confirmed to be the main active groups that could combine with silver ions. ? (2013) Trans Tech Publications, Switzerland

Plant-Mediated Fabrication and Surface Enhanced Raman Property of Flower-Like Au@Pd Nanoparticles

The flower-like nanostructures of an Au core and Pd petals with the average size of 47.8 nm were fabricated through the successive reduction of HAuCl4 and Na2PdCl4 at room temperature. During the synthesis, Cacumen Platycladi leaf extract served as weak reductant and capping agent. Characterization techniques such as Energy-dispersive X-ray spectroscopy, UV-Vis spectroscopy, and X-ray diffraction characterizations were employed to confirm that the as-synthesized nanoparticles have the structure of core-shell. The obtained core-shell nanoflowers exhibited good surface enhanced Raman spectroscopic activity with Rhodamine 6G

Preparation of Ag/alpha-Al2O3 for ethylene epoxidation through thermal decomposition assisted by extract of Cinnamomum camphora

NSFC [21206140, 21036004]; Natural Science Foundation of Fujian Province of China [20103J01059]An Ag/alpha-Al2O3 catalyst designed for application in the epoxidation of ethylene was prepared through thermal decomposition assisted by extract of Cinnamomum camphora. The effects of the reaction parameters on the catalytic performance were evaluated, including the extract concentration, calcining temperature and calcining time. The results demonstrated that the thermal decomposition should be conducted at 600 degrees C in N-2 for 60 min, assisted by 0.25 g mL(-1) Cinnamomum camphora extract. Compared with a simple thermal decomposition method, the sintering and aggregation of Ag particles and Ag loss during the reaction were alleviated by the presence of the catalyst that had been synthesized with the assistance of biomass

Preparation of Ag/α-Al2O3 for ethylene epoxidation through thermal decomposition assisted by extract of Cinnamomum camphora

An Ag/α-Al2O3 catalyst designed for application in the epoxidation of ethylene was prepared through thermal decomposition assisted by extract of Cinnamomum camphora. The effects of the reaction parameters on the catalytic performance were evaluated, including the extract concentration, calcining temperature and calcining time. The results demonstrated that the thermal decomposition should be conducted at 600 °C in N2 for 60 min, assisted by 0.25 g mL-1Cinnamomum camphora extract. Compared with a simple thermal decomposition method, the sintering and aggregation of Ag particles and Ag loss during the reaction were alleviated by the presence of the catalyst that had been synthesized with the assistance of biomass. ? The Royal Society of Chemistry 2013

Preparation of Ag/α-Al2O3 for ethylene epoxidation through thermal decomposition assisted by extract of Cinnamomum camphora

An Ag/α-Al2O3 catalyst designed for application in the epoxidation of ethylene was prepared through thermal decomposition assisted by extract of Cinnamomum camphora. The effects of the reaction parameters on the catalytic performance were evaluated, including the extract concentration, calcining temperature and calcining time. The results demonstrated that the thermal decomposition should be conducted at 600 °C in N2 for 60 min, assisted by 0.25 g mL-1Cinnamomum camphora extract. Compared with a simple thermal decomposition method, the sintering and aggregation of Ag particles and Ag loss during the reaction were alleviated by the presence of the catalyst that had been synthesized with the assistance of biomass. ? The Royal Society of Chemistry 2013

Green synthesis of Au-Ag alloy nanoparticles using Cacumen platycladi extract

An environmentally-friendly method for the synthesis of Au-Ag alloy nanoparticles with controlled composition is proposed. The method involves the simultaneous bioreduction of HAuCl4 and AgNO3 using Cacumen Platycladi leaf extract at 90 degrees C. The formation of the Au-Ag alloy nanoparticles was monitored by recording the absorbance, using UV-visible light spectroscopy as a function of the reaction time and the formation process. The as-synthesized nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy to verify the nature of the alloy. The Fourier transform infrared spectra show that the C=C, N-H, (NH) C=O, and -OH groups in the C. Platycladi extract served as a reducing agent, whereas the peptides or proteins prevented the aggregation of alloy nanoparticles. The process can be described as a purely "green technique'' because no additional synthetic reagents were used as reductants or stabilizers

Investigation of active biomolecules involved in the nucleation and growth of gold nanoparticles by Artocarpus heterophyllus Lam leaf extract

NSFC [21206140, 21106117, 21036004]The effects of different biomolecules in Artocarpus heterophyllus Lam leaf extract on the morphology of obtained gold nanoparticles were investigated in this study. The results indicated that reducing sugars, flavones, and polyphenols consisting of about 79.8 % dry weight of the leaf extract were mainly involved in providing the dual function of reduction and the size/shape control during the biosynthesis. The gold nanoparticles present included 64 +/- 10 nm nanospheres, 131 +/- 18 nm nanoflowers, and 347 +/- 136 nm (edge length) nanoplates and they were synthesized using the main content of reducing sugars, flavones, and polyphenols, respectively, after they were desorbed by the AB-8 macroporous adsorption resin column. Particularly, flower-like and triangular/hexagonal gold nanoparticles with a yield more than 80 % were obtained. Possible shape-directed agents for the nucleation and growth were characterized by FTIR, it can be seen that ketones were bound on the surface of the spherical and flower-like GNPs, while both the ketones and carbonyls bound on the Au {111} plane this may have favored the formation of the twin defects, which are very essential for nanoplates' formation