Recently, CulnS2/ZnS nanocrystals （CISZ NCs） have been widely used in many fields due to their excellent properties, such as tunable photoluminescence （PL） spectra, broad absorption, and non-toxicity. In order to ...Recently, CulnS2/ZnS nanocrystals （CISZ NCs） have been widely used in many fields due to their excellent properties, such as tunable photoluminescence （PL） spectra, broad absorption, and non-toxicity. In order to expand the application ofCISZ NCs, Gd3＋ was introduced into the host serving as paramagnetic modules to achieve magnetic resonance imaging （MRI） enhancement. MRI probes could provide high-resolution anatomical information. The derived Gd-Cu-In-S/ZnS nanocrystals （GCISZNCs） exhibited the strong orange photoluminescence with a quantum yield of 57.6% and significantly high longitudinal relaxivity （rl-20.4 mmol/s） in comparison with commmercial Magnevist （Gd-DTPA, r1=4.5mmol/s）. Effective enhancement of MRI and improved longitudinal relaxivity as well as lower cytotoxicity mode GCISZ NCs an ideal MRI probe, suggesting its potential and significance in practical biological and clinic applications in the future.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
Pyrex glasses with different ZnS: Mn^(2+) contents were prepared by melting method. It has been found that Mn ion may occupy two sites: (Mn^(2+) )sub and (Mn^(2+) )int from photoluminescene (PL) and photoluminescence ...Pyrex glasses with different ZnS: Mn^(2+) contents were prepared by melting method. It has been found that Mn ion may occupy two sites: (Mn^(2+) )sub and (Mn^(2+) )int from photoluminescene (PL) and photoluminescence excitation (PLE) spectra. The results were confirmed by the further electron paramagnetic resonance (EPR) experiments and the three types of states (Mn^(2+) )sub, (Mn^(2+) )int and Mn clusters were identified. It was observed that the g-factor and the hyperfine structure (HFS) constant increase with the decreasing size of nanocrystallite. This may result from hybridization of sp3 electron states of ZnS and 3d5 electron states of Mn by the effects of quantum confinement and the surface states.展开更多
基金Project supported by the National Natural Science Foundation of China(51472087)Shanghai Municipal Natural Science Foundation(13ZR1412500)+1 种基金Innovation Program of Shanghai Municipal Education Commission(14ZZ050)the ECNU Reward for Out-standing Doctoral Dissertation Cultivation Plan of Action(PY2015041)
文摘Recently, CulnS2/ZnS nanocrystals （CISZ NCs） have been widely used in many fields due to their excellent properties, such as tunable photoluminescence （PL） spectra, broad absorption, and non-toxicity. In order to expand the application ofCISZ NCs, Gd3＋ was introduced into the host serving as paramagnetic modules to achieve magnetic resonance imaging （MRI） enhancement. MRI probes could provide high-resolution anatomical information. The derived Gd-Cu-In-S/ZnS nanocrystals （GCISZNCs） exhibited the strong orange photoluminescence with a quantum yield of 57.6% and significantly high longitudinal relaxivity （rl-20.4 mmol/s） in comparison with commmercial Magnevist （Gd-DTPA, r1=4.5mmol/s）. Effective enhancement of MRI and improved longitudinal relaxivity as well as lower cytotoxicity mode GCISZ NCs an ideal MRI probe, suggesting its potential and significance in practical biological and clinic applications in the future.
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Project supported by the National Natural Science Foundation of ChinaLaboratory of Excited State Processes, Chinese Academy of Sciences
文摘Pyrex glasses with different ZnS: Mn^(2+) contents were prepared by melting method. It has been found that Mn ion may occupy two sites: (Mn^(2+) )sub and (Mn^(2+) )int from photoluminescene (PL) and photoluminescence excitation (PLE) spectra. The results were confirmed by the further electron paramagnetic resonance (EPR) experiments and the three types of states (Mn^(2+) )sub, (Mn^(2+) )int and Mn clusters were identified. It was observed that the g-factor and the hyperfine structure (HFS) constant increase with the decreasing size of nanocrystallite. This may result from hybridization of sp3 electron states of ZnS and 3d5 electron states of Mn by the effects of quantum confinement and the surface states.
