纳米材料的应用PPT课件

1、2021-11-191trans-Azobenzenecis-Azobenzene研究背景第1页/共12页2021-11-192Figure 4. (d) Sketch of the gate switching mechanism with a space-filling model of a pore window of UiO-67 and AZB in the cis conformation on the left and the trans conformation on the right. Oxygens are colored red, nitrogens green, ca

2、rbons of the MOF gray, carbons of the AZB orange, and zirconiums blue. Hydrogen atoms are hidden.365nm455nm第2页/共12页2021-11-193Figure 1. UiO-67 layer investigated by (a) XRD, (b) SEM, and (c) EDX mapping. The crystal structure of UiO-67 is shown in panel (d). The UiO-67 layer is very thin (200 nm), a

3、s shown in panel (c), so that XRD gives only low reflex intensities. XRD shows strong support reflexes that are denoted with asterisks in panel (a). However, the reflexes could be identified as UiO-67. Permeances for the neat UiO-67 layer without AZB loading are given as follows. The single-gas perm

4、eances and ideal permselectivities (in a hypothetical mixture with H2) are shown in panels (e) and (f), respectively. The mixed-gas permeances and real permselectivities for H2-containing mixtures are given in panel (g). 次级结构单元Zr6O4(OH)412+ 膜的合成与表征第3页/共12页应用：1.混合气体的分离2.传感器中的分子开关3.微电子学中的分子开关2021-11-1

5、94第4页/共12页2021-11-195第5页/共12页一、通过模板牺牲法对MOF晶体内的MNPs进行空间定位Fig.1 Through surface modification with surfactant PVP, MNPs of various sizes, shapes and compositions are loaded on the surface of metal oxide, and by reacting the metal oxide/MNPs template with organicligands, MNPs can be encapsulated in MOF

6、crystals. The spatial distribution of incorporated MNPs within MOF crystals can be controlled by tuning thecrystallization behaviour of MOFs under (a) high and (b) low concentration of the organic ligands.2021-11-196第6页/共12页二、将Au NPs融入ZIF-8进行空间调控Fig.2 TEM images of (a) ZnO NRs, (b) ZnO NRsAu and (c,

7、d) ZnO NRsAuZIF-8 composites with Au NPs at different locations: (c) inside and (d) near to the surface of ZIF-8. Scale bar, 100 nm2021-11-197第7页/共12页Figure3 Synthesis of ZnOZIF-8 with extra SiO2 under different concentration of Hmim. TEM images of the products under (a, b) high concentration and (c

8、, d) low concentration of Hmim. Micrographs b and d show the difference of the surface of SiO2 in the two cases. (b) The conversion of ZnO into ZIF-8 crystals is followed by the dissolution-precipitation mechanism at high ligand concentration, resulting in ZIF-8 crystals that are nucleated onto SiO2

9、surfaces. (d) The conversion of ZnO into ZIF-8 crystals is followed by the localized conversion mechanism at low ligand concentration; thus, ZIF-8 crystals would nucleate only onto the surfaces of ZnO. Scale bar, 1 mm (a,c) and 200 nm (b,d).2021-11-198第8页/共12页Figure 6 | Catalytic properties of ZnOPt

10、ZIF-8 composites for olefin hydrogenation. (a) Size-selective hydrogenation of n-hexene and cyclooctene catalysed by ZnOPtZIF-8 composite (3.3 nm Pt NPs with content of 0.9%); (b) the reusability of PtZIF-8-sur as catalysts for the hydrogenation of hexene for five consecutive runs. Reaction conditions: 0.01 g of catalyst, 0.1 ml of substrate, 3 ml of ethyl acetate, 1 atm of hydrogen, 35 C, reaction time of 12 h. Pure ZIF-8