制备了Mn掺杂Zn-In-S量子点并研究了Zn/In的量比和反应温度对其发光性质的影响。在Mn掺杂的Zn-In-S量子点的发光谱中观测到一个600 nm发光带。通过改变Zn/In的量比,掺杂量子点的吸收带隙可从3.76 e V(330 nm)调谐到2.82 e V(440 nm),但6...制备了Mn掺杂Zn-In-S量子点并研究了Zn/In的量比和反应温度对其发光性质的影响。在Mn掺杂的Zn-In-S量子点的发光谱中观测到一个600 nm发光带。通过改变Zn/In的量比,掺杂量子点的吸收带隙可从3.76 e V(330 nm)调谐到2.82 e V(440 nm),但600 nm发光峰的波长只有略微移动。这些掺杂量子点的最长荧光寿命为2.14 ms。当反应温度从200℃增加到230℃时,掺杂量子点的发光强度增加并达到最大值;而继续升高温度至260℃时,发光强度迅速减弱。此外,测量了Mn掺杂Zn-In-S量子点的变温发光光谱。发现随着温度的升高,发光峰位发生蓝移,发光强度明显下降。分析认为,Mn掺杂Zn-In-S量子点的600 nm发光来自于Mn2+离子的4T1和6A1之间的辐射复合。展开更多
本文采用Mn^2＋掺杂和组装壳等技术,以变性牛血清白蛋白（d BSA）为稳定剂,探索水相合成新型掺杂-核壳结构Ag In S2：Mn@Zn S量子点的方法。工作中以产物的荧光和磷光强度为指标,通过考察Mn^2＋和Zn的用量、反应的气氛、p H值、温度和...本文采用Mn^2＋掺杂和组装壳等技术,以变性牛血清白蛋白（d BSA）为稳定剂,探索水相合成新型掺杂-核壳结构Ag In S2：Mn@Zn S量子点的方法。工作中以产物的荧光和磷光强度为指标,通过考察Mn^2＋和Zn的用量、反应的气氛、p H值、温度和时间来优化Ag In S2：Mn@Zn S量子点的合成条件。用扫描隧道显微镜、X射线粉末衍射等技术对量子点的形貌、结构进行了表征。结果表明,该量子点的直径为9^11nm,量子产率为43.2%。用荧光光谱等方法研究了其光致发光性能,并应用于对胰蛋白酶的选择性识别。展开更多
A series of Na-W-Mn-Zr/SiO2 catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on t...A series of Na-W-Mn-Zr/SiO2 catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on the Na-W-Mn-Zr/SiO2 catalyst. The catalysts were characterized by X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS）. From the characterization results, it is found that the addition of S and P to the Na-W-Mn-ZffSiO2 catalyst helps the formation of active phases, such as α-cristobalite, Na2WO4, ZrO2, and Na2SO4. Moreover, the addition of S and P increases the concentration of surface-active oxygen species by improving the migration of active components from the bulk phase to the surface of the catalyst. According to the activity test, impressive methane conversion and C2 hydrocarbons yield were obtained at a low temperature of 1023 K over the six-component Na-W-Mn-Zr-S-P/SiO2 catalyst, which contained 2 wt% S and 0.4 wt% P simultaneously. The deactivation of Na-W-Mn-Zr-S-P/SiO2 was due to the loss of surface active components.展开更多
文摘本文采用Mn^2＋掺杂和组装壳等技术,以变性牛血清白蛋白（d BSA）为稳定剂,探索水相合成新型掺杂-核壳结构Ag In S2：Mn@Zn S量子点的方法。工作中以产物的荧光和磷光强度为指标,通过考察Mn^2＋和Zn的用量、反应的气氛、p H值、温度和时间来优化Ag In S2：Mn@Zn S量子点的合成条件。用扫描隧道显微镜、X射线粉末衍射等技术对量子点的形貌、结构进行了表征。结果表明,该量子点的直径为9^11nm,量子产率为43.2%。用荧光光谱等方法研究了其光致发光性能,并应用于对胰蛋白酶的选择性识别。
基金supported by the National Natural Science Foundation of China (20676116)
文摘A series of Na-W-Mn-Zr/SiO2 catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on the Na-W-Mn-Zr/SiO2 catalyst. The catalysts were characterized by X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS）. From the characterization results, it is found that the addition of S and P to the Na-W-Mn-ZffSiO2 catalyst helps the formation of active phases, such as α-cristobalite, Na2WO4, ZrO2, and Na2SO4. Moreover, the addition of S and P increases the concentration of surface-active oxygen species by improving the migration of active components from the bulk phase to the surface of the catalyst. According to the activity test, impressive methane conversion and C2 hydrocarbons yield were obtained at a low temperature of 1023 K over the six-component Na-W-Mn-Zr-S-P/SiO2 catalyst, which contained 2 wt% S and 0.4 wt% P simultaneously. The deactivation of Na-W-Mn-Zr-S-P/SiO2 was due to the loss of surface active components.
