Silver nanorods have been successfully synthesized in large scale by the ethylene glycol（EG） reduction in the presence of ionic liquid（IL） 1-butyl-3-methylimidazolium tetrafluoroborate（bmimBF_4） and polyvinyl-py...Silver nanorods have been successfully synthesized in large scale by the ethylene glycol（EG） reduction in the presence of ionic liquid（IL） 1-butyl-3-methylimidazolium tetrafluoroborate（bmimBF_4） and polyvinyl-pyrrolidone（PVP）.The silver nanorods were characterized by scanning electron microscopy（SEM）,high-resolution transmission electron microscopy（HRTEM）,transmission electron microscopy（TEM）,electron energy disperse spectroscopy（EDS） and UV-vis spectroscopy.The results showed that the uniform silver nanorods have an average diameter of about 100 nm and the aspect ratio from 15 to 20.IL,bmimBF_4 may play a role of capping agent together with PVP in the formation of silver nanorods.On the other band,bmimBF_4 may accelerate nucleation and improve the stability of the resulting Ag nanorods due to the low interface tension of IL.展开更多
The determination of pesticide residue on agricultural products is increasingly important. Exposure to pesticides can cause severe acute reactions in humans, including aplastic anemia and leukemia. In this work, we de...The determination of pesticide residue on agricultural products is increasingly important. Exposure to pesticides can cause severe acute reactions in humans, including aplastic anemia and leukemia. In this work, we developed a rapid and sensitive method to detect acetamiprid pesticide residue based on surface-enhanced Raman scattering. Silver nanorod （AgNR） arrays were fabricated by oblique angle deposition technology and were used as SERS substrates. Prior to detection, the AgNR arrays were cleaned with nitric acid solution or a mixture of methanol and acetone. Compared to the unwashed AgNR arrays, the AgNR arrays washed with methanol and acetone shows a signal enhancement 1000 times greater than the unwashed AgNR array due to the effective removal of the impurities on its surface. The limit of detection of acetamiprid was determined to be 0.05 mg/L. In addition, the molecular structure of acetamiprid was simulated and the corresponding vibration modes of the characteristic bands of acetamiprid were calculated by density function theory. To demonstrate its practical application, the AgNRs array substrates were applied successfully to the rapid identification of acetamiprid residue on a cucumber＇s surface. These results confirmed possibility of utilizing the AgNRs SERS substrates as a new method for highly sensitive pesticide residue detection.展开更多
We investigate the power-dependent luminescence of CdSe/ZnS semiconductor quantum dots closely packed layer- by-layer in the proximity of a silver nanorod array cavity. It is found that the emission peak shifts signif...We investigate the power-dependent luminescence of CdSe/ZnS semiconductor quantum dots closely packed layer- by-layer in the proximity of a silver nanorod array cavity. It is found that the emission peak shifts significantly to the longer wavelengths as the excitation power increases, especially when the longitudinal surface plasmon resonance of the Ag nanorod array cavity is adjusted to be close to the emission wavelength. The equivalent gain varies with the coating layer of CdSe/ZnS semiconductor quantum dots and the excitation power is also studied to explain this interesting spectrum-shifting effect. These findings could find applications in the dynamic information processing of active plasmonic and photonic nanodevices.展开更多
Through anisotropic Ag overgrowth on the surface of Au nanobipyramids(Au NBPs), high-purity and sizecontrolled Ag nanorods(Au/Ag NRs) are obtained by a simplified purification process. The diameters of the Au/Ag NRs a...Through anisotropic Ag overgrowth on the surface of Au nanobipyramids(Au NBPs), high-purity and sizecontrolled Ag nanorods(Au/Ag NRs) are obtained by a simplified purification process. The diameters of the Au/Ag NRs are determined by the size of the as-prepared Au NBPs, and the lengths of the Au/Ag NRs are tunable using different amounts of Ag precursor in the growth solution. Surface-enhanced Raman scattering(SERS) studies using Rhodamine-6G(R6G) as a test molecule indicate that the Au/Ag NRs have excellent sensing potential. The tunable optical properties and strong electromagnetic effect of the Au/Ag NRs, along with their superior SERS signal enhancement, show that Au/Ag NRs are promising for further applications in plasmon sensing and biomolecular detection.展开更多
基金supported by the National Natural Science Foundation of China(No.20773081 and 20873074)National Basic Research Program(No.2007CB808004 and 2009CB930101)Laboratory of Organic Optoelectronic Functional Materials and Molecular Engineering,TIPC,CAS.
文摘Silver nanorods have been successfully synthesized in large scale by the ethylene glycol（EG） reduction in the presence of ionic liquid（IL） 1-butyl-3-methylimidazolium tetrafluoroborate（bmimBF_4） and polyvinyl-pyrrolidone（PVP）.The silver nanorods were characterized by scanning electron microscopy（SEM）,high-resolution transmission electron microscopy（HRTEM）,transmission electron microscopy（TEM）,electron energy disperse spectroscopy（EDS） and UV-vis spectroscopy.The results showed that the uniform silver nanorods have an average diameter of about 100 nm and the aspect ratio from 15 to 20.IL,bmimBF_4 may play a role of capping agent together with PVP in the formation of silver nanorods.On the other band,bmimBF_4 may accelerate nucleation and improve the stability of the resulting Ag nanorods due to the low interface tension of IL.
基金supported by the National Natural Science Foundation of China (No.61575087, No.21505057, and No.61771227)the Natural Science Foundation ofJiangsu Province (No.BK20151164, No.BK20150227, and No.BK20170229)+2 种基金the Innovation Project of Jiangsu Province(No.KYLX16_1322)the Natural Science Foundation of the Jiangsu Higher Education Institutions (No.17KJB140007)Foundation of Xuzhou City (No.KC15MS030)
文摘The determination of pesticide residue on agricultural products is increasingly important. Exposure to pesticides can cause severe acute reactions in humans, including aplastic anemia and leukemia. In this work, we developed a rapid and sensitive method to detect acetamiprid pesticide residue based on surface-enhanced Raman scattering. Silver nanorod （AgNR） arrays were fabricated by oblique angle deposition technology and were used as SERS substrates. Prior to detection, the AgNR arrays were cleaned with nitric acid solution or a mixture of methanol and acetone. Compared to the unwashed AgNR arrays, the AgNR arrays washed with methanol and acetone shows a signal enhancement 1000 times greater than the unwashed AgNR array due to the effective removal of the impurities on its surface. The limit of detection of acetamiprid was determined to be 0.05 mg/L. In addition, the molecular structure of acetamiprid was simulated and the corresponding vibration modes of the characteristic bands of acetamiprid were calculated by density function theory. To demonstrate its practical application, the AgNRs array substrates were applied successfully to the rapid identification of acetamiprid residue on a cucumber＇s surface. These results confirmed possibility of utilizing the AgNRs SERS substrates as a new method for highly sensitive pesticide residue detection.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11174229,11374236 and 11204221the National Basic Research Program of China under Grant No 2011CB922201
文摘We investigate the power-dependent luminescence of CdSe/ZnS semiconductor quantum dots closely packed layer- by-layer in the proximity of a silver nanorod array cavity. It is found that the emission peak shifts significantly to the longer wavelengths as the excitation power increases, especially when the longitudinal surface plasmon resonance of the Ag nanorod array cavity is adjusted to be close to the emission wavelength. The equivalent gain varies with the coating layer of CdSe/ZnS semiconductor quantum dots and the excitation power is also studied to explain this interesting spectrum-shifting effect. These findings could find applications in the dynamic information processing of active plasmonic and photonic nanodevices.
基金National Natural Science Foundation of China(NSFC)(11274173,11374159)Jiangsu Innovation Program for Graduate Education(KYZZ_0091)+1 种基金Scientific Foundation of Nanjing Institute of Technology(CKJB201411,QKJB201409,YKJ201538)Qing Lan Project and Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Through anisotropic Ag overgrowth on the surface of Au nanobipyramids(Au NBPs), high-purity and sizecontrolled Ag nanorods(Au/Ag NRs) are obtained by a simplified purification process. The diameters of the Au/Ag NRs are determined by the size of the as-prepared Au NBPs, and the lengths of the Au/Ag NRs are tunable using different amounts of Ag precursor in the growth solution. Surface-enhanced Raman scattering(SERS) studies using Rhodamine-6G(R6G) as a test molecule indicate that the Au/Ag NRs have excellent sensing potential. The tunable optical properties and strong electromagnetic effect of the Au/Ag NRs, along with their superior SERS signal enhancement, show that Au/Ag NRs are promising for further applications in plasmon sensing and biomolecular detection.
基金supported by National Science Foundation of China(No.20973142,No.21061120456,and No.21021002)National Basic Research Program of China(2011CB933700)+1 种基金the National Science Foundation(CHE-1026582MVM)
