化学研究生工作报告.ppt

Stable photocatalytic hydrogen evolution from water over ZnOCdS coreshell nanorods,internaioal journal of hydrogen energy 35 (2010) 81998205,Preparation of photocatalysts ZnOCdS :,0.1 M Zn(CH3COO)2.2H2O, 0.6 M C6H12N4 溶解在50ml蒸馏水中,20 mL Cd(CH3COO)2.2H2O,95,10h,ZnO,超声1h,80磁力加热搅拌,400烧1-3h,ZnOCdO,400通 H2S 0.5-2h,ZnOCdS,SEM images of (A) ZnO nanorods and (B) (ZnO)1(CdS)0.2 coreshell nanorods, (C) TEM image of (ZnO)1(CdS)0.2 coreshell nanorods and (D) high resolution TEM image of CdS particle coated on ZnO nanorods.,从SEM图中可以看出ZnO和(ZnO)1(CdS)0.2 的形貌似杆状， ZnO的表面比 (ZnO)1(CdS)0.2 的光滑一些，从C图TEM图中也可以看出ZnO的表面确实复合了 CdS ，从D图高倍透射电镜中可以看出 晶格条纹间的距离为3.16A,(A) XRD patterns of reference ZnO, CdS and (ZnO)1(CdS)0.2 coreshell nanorods; (B) UVvisible absorption spectra of ZnO, the ZnOCdS coreshell nanorods (ZnO)1(CdS)x,x =0.1, 0.2, 0.3, 0.4, 0.5, and 0.6, are denoted as 101, 102, 103, 104, 105, 106, respectively), and CdS.,上图A为样品的XRD衍射峰，所有的峰均为六方晶系，从图中也可以看出CdS的衍射峰比(ZnO)1(CdS)0.2 中CdS的衍射峰尖锐，表明样品颗粒的比表面积小。B图为样品的紫外吸收光谱，从图中可以看出复合的样品光吸收范围增加到可见光范围，随着CdS比例的增加，对吸收边缘影响不大。,Comparison of the photocatalytic H2 evolution rate of CdS particles, ZnO nanorods, and the ZnOCdS coreshell nanorods, where (ZnO)1(CdS)x (x=0.1, 0.2, 0.3, 0.4,0.5, 0.6) are denoted as 101, 102, 103, 104, 105 and 106,respectively.,图为样品的催化分解水产氢的效率图，从图中可以看出，复合后样品的光催化效率明显提高，当CdS的含量为0.2时，催化效果最好，随着CdS含量的增加，催化效果逐渐降低，主要是因为随着CdS含量的增加，ZnO的反应位点减少。,Comparison of the amount of H2 evolution of the (ZnO)1(CdS)0.2 nanorods prepared under H2S flow (A) at different temperature for 1 h and (B) at 400 for different time.,从上面A图中可以看出在400时，复合样品的光催化分解水产氢效率最好，从B中知道当温度为400时，反应1h氢的量最多。,(A) Hydrogen evolution comparison of (ZnO)1(CdS)0.2 coreshell nanorods with loaded 1 wt% Pt and 1 wt% RuO2,respectively, and (B) effects of the content of RuO2 on photocatalytic H2 evolution of the (ZnO)1(CdS)0.2 coreshell nanorods.,图A是给(ZnO)1(CdS)0.2分别加了1 wt%Pt 和 1 wt% RuO2作为助催化剂，从图中可以看出，加了1 wt% RuO2的催化剂催化效果更好，B图是加了不同量的RuO2的比较，可以看出RuO2的量为1 wt% 时催化效率最好。,Time courses of water splitting over the (ZnO)1(CdS)0.2 coreshell nanorods (solid square) and RuO2(1 wt%)-loaded (ZnO)1(CdS)0.2 coreshell nanorods (solid circle). The reaction was continued for 30 h, with evacuation every 10 h (solid vertical line).,图为(ZnO)1(CdS)0.2和RuO2(1 wt%)负载的 (ZnO)1(CdS)0.2 的光稳定性示意图，从图中可以看出反应30h内，光催化剂对光比较稳定。,High resolution XPS spectra of Zn 2p (A), O 1s (B), Cd 3d (C) and S 2p (D) in the (ZnO)1(CdS)0.2 coreshell nanorods, ZnO nanorods and CdS particles.,从上图X射线光电子能谱图中可以看出在(ZnO)1(CdS)0.2 中Zn 2p, O 1s, 和 S 2p轨道结合能都增大了，而 Cd 3d 轨道结合能减小了，结合能的改变表明在(ZnO)1(CdS)0.2 中ZnO和CdS有新的化学键形成。,Schematic of ZnOC