1、The Draft of Academic Presentation国际会议的口头报告模板,每页ppt你需要讲什么东西需要分页详细写,尽量口语化,如下是本人参加比利时会议的模板,供大家参考。P1开场白:I am so honored to be with you to communicate academic questions and ideas. The tile of my academic presentation is “The preparation and catalytic performance of porous silica nanotube functioned wit
2、h heteroatoms” I shall only take ten minutes of your time.I will talk about the topic on the preparation of porous materials.P2First of all, i wanna introduce myself. I come from nanjing university of technology, nanjing city, china.P3The content is listed as follows.P4All our researches are conduct
3、ed by the academic thoughts. Generally speaking, we are committed to porous materials. In order to explore high-performance functionalized materials for Pilotexperiments and scale-upproduction; we tune the structure, such as composition and morphology step by step and optimize them further. Whats mo
4、re, the possible synthesis mechanisms are also investigated. Today, the presentation is based on the right-hand branch.P5It is known that mesoporous silica have excellent characters as the catalyst carrier, such as.But due to lack of active sites, we have to introduce organic or inorganic species as
5、 active sites. And the catalytic performance need to be further improved. P6 As we know, the three factors including activity, scale and diffusion factor play decisive role in the catalysis, affecting the yield, selectivity, stability strongly. In our presentation, we mainly focus on the influence o
6、f scale factor on the catalysis. P7Due to lack of active sites for mesoporous silica, two main methods (surface loading, modified framework) are widely reported, by which various organic or inorganic active sites can be immobilized on the surface or incorporated into the framework of mesopoous silic
7、a.P8Though various morphologies of mesoporos silica were widely synthesized, the synthesis of the mesoporos silica, with three simultaneous characteristics including doped metal, mesoporous structure and specific morphology, is always a challenge, which is rarely reported. In other words, for our ca
8、se exploring a proper condition, at which the silicon and metal sources can simultaneously hydrolyze, can ensure a desired material. P9Next, lets look at the synthetic steps. Firstly,. Then, . After that, . At last, we obtained the products.P10In this work, by changing the synthesis conditions, such
9、 as , and so on, the pure mesoporous silica with different morphologies were synthesized, including nanosphere, nanorod, helix, capsule and nanotube. We will focus on the preparation and catalytic application of mesoporous silica with nanotube morphology.P11the SEM images of samples: A1, A2, A3 are
10、shown in the figure. It can be seen that sample a1 is nanowire-like with length of about 2m and diameter of about 100nm. When the amount of . is 0.04 g, the morphology of sample A2 became to be short and thick rods and the size is about 1m in length and 400nm in diameter, respectively. With further
11、increasing the amount of ., the sample A3 and A4 turned to be spherical morphology. It also can be seen that the diameters of samples A3 and A4 are substantially the same about 450nm. However, the spherical morphology of A4 is more regular than that of A3. The XRD patterns showed four reflection pea
12、ks attributed to (100), (110), (200) and (210), respectively, due to the hexagonal sructure. P12Then, we keep the same amount of ., increasing the amount of .We found that the length increased gradually. The XRD patterns also showed the hexagonal sructure of samples B1, B2, B3, B4.P13 Moreover, an a
13、dditional proof of the hexagonal symmetry structure is given by TEM and the FT pattern. The N2 adsorption-desorption isotherms of the samples B1, B2, B3, B4 exhibit a typical type-IV isotherm. According to the table of structural parameters, we can find that the specific surface area and total pore
14、volume increase gradually, the thickness of wall decrease and there is no obvious change in diameter.P14Furthermore, the possible synthesis mechanism of the mesoporous silica nanotube in dual templates system was proposed. We suggest that due to electrostatic repulsion between positively charged amm
15、onium ions from hydrated ammonia molecules and hydrophilic groups of ., especially in ammonia (NH3, 25wt.%) solution, the high concentrated ammonium ions provide a crowded and repulsive space to prevent the conjunction of . molecules, leading to the formation of the rod-like micelles as template to
16、form pore structure instead of sphere-like ones.The role of co-template . is suggested to tune the length of rod-like micelles by arranging itself along the axis of channel with PEO and PPO part immersed in the hydrophilic and the hydrophobic group of CTA+ respectively. As a result, the mesoporous n
17、anotube with different length will be synthesized. However, the non-polar . micelles are not affected by positively charged ammonium. When the amount of co-template increased further, the non-polar . micelles tend to control the morphology of micelles which are sequentially from nanotube, short rod
18、to sphere-like ones. It my be the reason that the non-polar . micelles would provide stronger attractive force than the electrostatic repulsion derived from the PEO block, ammonium ions and head group of ., respectively. P15In order to investigate the influence of the morphology and structure of mes
19、oporous silica on catalytic performance, the samples with copper incorporated were synthesized.P16 The figure shows the SEM and TEM images of samples a1, a2, a3, from which we can see they represent incremental length in the range of about 0.5, 1.0 and 1.5m, and insignificant change in diameter arou
20、nd 100nm. In XRD patterns, there are also four reflection peaks for the samples with copper incorprated, respectively, which indicates the incorporation of the inorganic copper salt has no obvious effect on the hexagonal sructure and the ordered degree of pore structure. Moreover, the trends in leng
21、th and the diameter of nanotube are illustrated.P17The N2 adsorption-desorption isotherms of the samples a1, a2, a3 exhibit a typical type-IV isotherm according to the IUPAC classification and no hysteresis loop at the relative pressure range of 0.2p/p00.4, implying the samples not only have ordered
22、 mesoporous structure but also the uniform pore size. Moreover, the pore diameters did not change significantly at different weight ratio of ./. The most probable pore sizes of samples a1, a2, a3 are determined to be 2.71, 2.50, 2.44 nm, respectively. The structural parameters are listed in followin
23、g table.P18This table summarized the catalytic activity of copper-modified porous silica nanotube in the direct hydroxylation of benzene with H2O2 as oxidant. The catalysts showed high catalytic activity, and direct proportional relationship between the benzene conversion and the length of the silic
24、a nanotube. Considering the similar copper content determined by ICP, the variations of catalytic activities were probably caused by different retention time of reagent in the nanotube with different lengths. P19It is Summary and Future ResearchThis part of research can be summed up from the following three aspects.Mophology control, Catalytic activity and Future research看this slide.P20thanks
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