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71.
SBA-15的二氧化钛改性及其光催化降解对氯苯酚 总被引:10,自引:0,他引:10
在“后合成”法在介孔二氧化硅SBA-15的孔壁表面键接了二氧化钛,并对其 结构进行了表征。改性后的SBA-15保持了规则的介孔结构,并在孔壁表面形成了 类似于锐钛型二氧化钛的Ti-O-Ti网络结构。光催化降解对氯苯酚的结果表明,经 过两次二氧化钛键接的样品表现出较高的光催化效率。但是由于对酚、醌等中间产 物的强烈吸附以及孔道中反应物质的扩散速度慢,使得其光催化活性略低于纯的锐 钛型二氧化钛。 相似文献
72.
通过对介孔SBA-15孔壁氨基化(SBA-15-NH2),然后与C60反应形成化学键,成功地将C60组装进入SBA-15孔道中,合成了C60/SBA-15介孔复合材料.通过X射线衍射(XRD)、红外光谱(FTIR)、紫外-可见光谱(UV-V is)和差热-热重分析(TG-DTA)等方法对其进行了表征.同时,对复合材料的荧光性质进行了研究.结果发现,SBA-15-NH2在575 nm处出现发射峰,C60/SBA-15介孔复合材料在554 nm处出现发射峰,峰位蓝移21 nm. 相似文献
73.
SBA-15的硅烷化对钴基催化剂费-托合成性能的影响 总被引:1,自引:0,他引:1
以未硅烷化和硅烷化的SBA-15为载体,采用满孔浸渍法制备了钴基费-托合成催化剂,通过元素分析、N_2吸附-脱附、X射线衍射、H_2程序升温还原、H_2程序升温脱附以及氧滴定等手段对催化剂进行了表征.催化剂的费-托合成活性测试在固定床反应器上进行.研究表明,对于SBA-15硅烷化后制备的催化剂,金属钴与载体之间的相互作用降低,氧化钴的还原度增加.随着三甲基氯硅烷用量的增加,三甲基硅基的表面覆盖度增加,钴的晶粒直径增大.硅烷化后的催化剂的高活性归因于高的还原度.而C_(5+)选择性的增加则归因于钴晶粒直径的增大. 相似文献
74.
Ann-Katrin Beurer Dr. Johanna R. Bruckner Prof. Dr. Yvonne Traa 《ChemistryOpen》2021,10(11):1123-1128
Removing the template from the pores after the polycondensation of the silica precursor is a necessary step in the synthesis of mesoporous silica materials. In our previous work, we developed a method for the efficient and spatially controlled functionalization of SBA-15. First, the silanol groups on the particle surface and in the pore entrances were passivated. After extraction of the template, a pretreatment step in N2 converted the silanol groups to the single and geminal state. Afterwards, an azide functionality was introduced exclusively into the mesopores. This ensured that the catalyst could afterwards be immobilized unambiguously in the mesopores. The mechanical stability of a material functionalized in such a spatially controlled manner is studied and compared to other template removal methods. Even though several studies investigated the influence of the calcination temperature, the presence or the absence of oxygen during the template removal, the specific conditions used during the herein reported selective functionalization procedure have not been covered yet. 相似文献
75.
Taiebeh Tamoradi Mohammad Ghadermazi Arash Ghorbani-Choghamarani 《Journal of Saudi Chemical Society》2019,23(7):846-855
In the present study, oxidative coupling of thiols was carried out using immobilized Cu, Ni and Pd complexes on SBA-15 mesostructured as novel and green heterogeneous catalysts under mild reaction conditions. These supported complexes were characterized by FT-IR, XRD, TEM, TGA, EDX, ICP and BET techniques. These nanohybrid robust catalysts have outstanding advantages such as facile synthesis, use of green medium, high surface area, easy separation and workup, excellent reused for several consecutive cycles without noticeable change in its catalytic activity, and short reaction time. 相似文献
76.
采用水热合成法制备介孔分子筛SBA-15,用(CH3COO)2Co对其进行超声浸渍改性,并用硅烷偶联剂APTS将氨基引入SBA-15分子筛中,制备出Co-NH2-SBA-15吸附剂,考察了常温条件下H2S的吸附性能。通过SEM、XRD、FT-IR、BET、XPS等表征手段对吸附剂进行表征。结果表明,氨基与金属同时负载在分子筛表面,氨基与硅物质的量比为0.20,Co负载质量分数为8%的SBA-15吸附效果最好,当原料气H2S体积分数为227 μL/L,温度25 ℃,气体流量75 mL/min时,穿透硫容和饱和硫容达0.151和0.190 mmol/g,且吸附剂可再生利用。SBA-15表面嫁接氨基并浸渍金属改性的手段不仅提高了吸附容量,同时提高了分子筛的稳定性。 相似文献
77.
A novel method for the immobilization of acetylcholinesterase (AChE) on amino modified SBA-15 mesoporous molecular sieves was developed via electrostatic adsorption and glutaraldehyde crosslinking. The immobilized AChE could be exploited as a fast, sensitive and low-cost biocatalyst towards the detection of pesticides residues which could be stored at room temperature for a long time. 相似文献
78.
Chun Tao Yue Yu Zhenzhen Chen Minxin Zhang Linlin Liu Zhihong Liu Jialiang Zhang Qian Zhang Hongtao Song 《中国化学快报》2018,29(12):1849-1852
The mesoporous silica materials had a high loading efficiency of sirolimus-SMEDDS. The length of the mesopores played a more important role than the pore diameter in drug dissolution and in vivo absorption. 相似文献
79.
Highly Crystalline Mesoporous C60 with Ordered Pores: A Class of Nanomaterials for Energy Applications 下载免费PDF全文
Mercy R. Benzigar Stalin Joseph Hamid Ilbeygi Dr. Dae‐Hwan Park Dr. Sujoy Sarkar Dr. Goutam Chandra Prof. Siva Umapathy Prof. Sampath Srinivasan Dr. Siddulu Naidu Talapaneni Prof. Ajayan Vinu 《Angewandte Chemie (International ed. in English)》2018,57(2):569-573
Highly ordered mesoporous C60 with a well‐ordered porous structure and a high crystallinity is prepared through the nanohard templating method using a saturated solution of C60 in 1‐chloronaphthalene (51 mg mL?1) as a C60 precursor and SBA‐15 as a hard template. The high solubility of C60 in 1‐chloronaphthalene helps not only to encapsulate a huge amount of the C60 into the mesopores of the template but also supports the oligomerization of C60 and the formation of crystalline walls made of C60. The obtained mesoporous C60 exhibits a rod‐shaped morphology, a high specific surface area (680 m2 g?1), tuneable pores, and a highly crystalline wall structure. This exciting ordered mesoporous C60 offers high supercapacitive performance and a high selectivity to H2O2 production and methanol tolerance for ORR. This simple strategy could be adopted to make a series of mesoporous fullerenes with different structures and carbon atoms as a new class of energy materials. 相似文献
80.