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1.
In this study, mesoporous TiO2 microspheres were synthesized by simple hydrothermal reaction, and successfully developed for phosphopeptides enrichment from both standard protein digestion and real biological sample such as rat brain tissue extract. The mesoporous TiO2 microspheres (the diameter size of about 1.0 μm) obtained by simple hydrothermal method were found to have a specific surface area of 84.98 m2/g, which is much larger than smooth TiO2 microspheres with same size. The surface area of mesoporous TiO2 microspheres is almost two times of commercial TiO2 nanoparticle (a diameter of 90 nm). Using standard proteins digestion and real biological samples, the superior selectivity and capacity of mesoporous TiO2 microspheres for the enrichment of phosphorylated peptides than that of commercial TiO2 nanoparticles and TiO2 microspheres was also observed. It has been demonstrated that mesoporous TiO2 microspheres have powerful potential for selective enrichment of phosphorylated peptides. Moreover, the preparation of the mesoporous TiO2 microspheres obtained by the hydrothermal reaction is easy, simple and low-cost. These mesoporous TiO2 microspheres with the ability of large scale synthesis can widely be applied for phosphorylated proteomic research.  相似文献   

2.
《中国化学会会志》2018,65(4):424-429
In this study, we propose a time‐ and energy‐saving method using biodegradable gelatin as a green template and a low‐toxicity inorganic aluminum salt (Al(NO3)3·9H2O) as a low‐cost aluminum source for the preparation of mesoporous alumina (γ‐Al2O3). The effects of pH (pH 8.0–10.0), gelatin to aluminum source ratio (0–1.9), and the hydrothermal treatment time (0–72 h) are thoroughly explored. The gelatin can assemble with the aluminum species γ‐AlOOH via hydrogen bonding to prevent the self‐condensation of the γ‐AlOOH during the hydrothermal treatment. Distinctly, the mesoporous γ‐Al2O3 was obtained from the calcination of the resulting gelatin–γ‐AlOOH composites. Without gelatin, high‐crystallinity γ‐AlOOH formed after the hydrothermal treatment, which transformed into the nonporous γ‐Al2O3 with a small surface area (20 m2/g). Finally, it was found that with a gelatin/aluminum ratio of 0.81, reaction pH value of 8.0, and hydrothermal treatment time of 24 h, high‐surface‐area mesoporous γ‐Al2O3 (262 m2/g) with pore diameter of 6.3 nm could be synthesized.  相似文献   

3.
在本文,采用水热法合成了一种新型的介孔二氧化钛/碳/亚甲蓝复合纳米团簇(TiO2@C-MB),并应用于肿瘤细胞的光动力(PDT)和光热治疗(PTT)。系统中介孔二氧化钛作为有效的光敏剂,MB作为重要的光敏添加剂以改善二氧化钛纳米晶的光化学效应,并将其光响应区域拓宽至光动力学疗法的理想治疗窗(650~900 nm)。柠檬酸在水热条件下被还原成碳并裹覆在二氧化钛表面。碳层表现出良好的光热效果,也充当多功能的电子受体以加速生成单线态氧。该纳米团簇不仅可以保持肿瘤细胞内部高浓度的MB和二氧化钛以产生大量的单线态氧杀死肿瘤细胞,而且可以避免MB退化失活。  相似文献   

4.
Mesoporous wall‐structured TiO2 on reduced graphene oxide (RGO) nanosheets were successfully fabricated through a simple hydrothermal process without any surfactants and annealed at 400 °C for 2 h under argon. The obtained mesoporous structured TiO2–RGO composites had a high surface area (99 0307 m2 g?1) and exhibited excellent electrochemical cycling (a reversible capacity of 260 mAh g?1 at 1.2 C and 180 mAh g?1 at 5 C after 400 cycles), demonstrating it to be a promising method for the development of high‐performance Li‐ion batteries.  相似文献   

5.
A mesoporous flake‐like manganese‐cobalt composite oxide (MnCo2O4) is synthesized successfully through the hydrothermal method. The crystalline phase and morphology of the materials are characterized by X‐ray diffraction, field‐emission scanning electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller methods. The flake‐like MnCo2O4 is evaluated as the anode material for lithium‐ion batteries. Owing to its mesoporous nature, it exhibits a high reversible capacity of 1066 mA h g?1, good rate capability, and superior cycling stability. As an electrode material for supercapacitors, the flake‐like MnCo2O4 also demonstrates a high supercapacitance of 1487 F g?1 at a current density of 1 A g?1, and an exceptional cycling performance over 2000 charge/discharge cycles.  相似文献   

6.
This is a review of our recent reports about improving the hydrothermal stability of MCM-48 mesoporous molecular sieves and the related works done by other groups. It presents the different effects of direct addition of various anions, including F?, SO4 2?, NO3 ? and Cl?, on the improvement of the hydrothermal stability of MCM-48. The different effects of anions on the improvement of the hydrothermal stability and the critical factors influencing the formation of hydrothermally stable MCM-48 are also explained by careful analysis and discussion.  相似文献   

7.
Nanocrystalline mesoporous TiO2 was synthesized by hydrothermal method using titanium butoxide as starting material. XRD, SEM, and TEM analyses revealed that the synthesized TiO2 had anatase structure with crystalline size of about 8 nm. Moreover, the synthesized titania possessed a narrow pore size distribution with average pore diameter and high specific surface area of 215 m2/g. The photocatalytic activity of synthesized TiO2 was evaluated with photocatalytic H2 production from water-splitting reaction. The photocatalytic activity of synthesized TiO2 treated with appropriate calcination temperature was considerably higher than that of commercial TiO2 (Ishihara ST-01). The utilization of mesoporous TiO2 photocatalyst with high crystallinity of anatase phase promoted great H2 production. Furthermore, the reaction temperature significantly influences the water-splitting reaction.  相似文献   

8.
A porous, high surface area TiO2 with anatase or rutile crystalline domains is advantageous for high efficiency photonic devices. Here, we report a new route to the synthesis of mesoporous titania with full anatase crystalline domains. This route involves the preparation of anatase nanocrystalline seed suspensions as the titania precursor and a block copolymer surfactant, Pluronic P123 as the template for the hydrothermal self-assembly process. A large pore (7–8 nm) mesoporous titania with a high surface area of 106–150 m2/g after calcination at 400°C for 4 h in air is achieved. Increasing the hydrothermal temperature decreases the surface area and creates larger pores. Characteristics of the seed precursors as well as the resultant mesoporous titania powder were studied using XRD analysis, N2-adsorption/desorption analysis, and TEM. We believe these materials will be especially useful for photoelectrochemical solar cell and photocatalysis applications.  相似文献   

9.
Mesoporous TiO2 microspheres with high specific surface areas were synthesized by means of a facile one‐step microwave hydrothermal process without using any template. The mesoporous materials were rapidly achieved using TiCl4, urea and ammonium sulphate at comparatively low microwave power (400 W) for 8 min irradiation. The morphology and microstructure of the as‐prepared products were characterized by field emission scanning electron microscopy (FESEM), X‐ray diffraction (XRD), transmission electron microscopy (TEM) and Brunauer‐Emmett‐Teller (BET) surface area analysis. Structural characterization indicates that the TiO2 microspheres display mesoporous structure. The average pore sizes and BET surface areas of the spheres were 5.3 nm and 222 m2g?1, respectively. The mesoporous nanocrystals synthesized at 160 °C for 8 min were then used to prepare the photoanode for dye sensitized solar cells (DSSCs). A high power conversion efficiency of 5.72% was achieved from the mesoporous TiO2 based photoanode, representing about 25.7% improvement over the efficiency of P25 photoanode.  相似文献   

10.
We report a one‐step convenient chemical coating method of high alumina content onto mesoporous silicas. Aluminia‐coated mesoporous silica with high surface area (?900 m2/g), tuneable pore size (2.0–3.0 nm) and high hydrothermal stability (> 60 h) is obtained. The method may also be generalized for grafting other metal oxides onto mesoporous silica in future work.  相似文献   

11.
Poorly crystalline mesoporous MnO2, which is suitable for supercapacitor studies, is synthesized from neutral KMnO4 aqueous solution by hydrothermal route. But it requires a high temperature (180 °C) and also a long reaction time (24 h). Addition of a tri-block copolymer, namely, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123), which is generally used as a soft template for the synthesis of nano-structured porous materials, reduces the hydrothermal temperature to 140 °C and also reaction time to 2 h. When the reaction time is increased, the product morphology changes from nanoparticles to nanorods with a concomitant decrease in BET surface area. Also, the product tends to attain crystallinity. The electrochemical capacitance properties of MnO2 synthesized under varied hydrothermal conditions are studied in 0.1 M Na2SO4 electrolyte. A specific capacitance of 193 F?g?1 is obtained for the mesoporous MnO2 sample consisting of nanoparticle and nanorod mixed morphology synthesized in 6 h using P123 at 140 °C.  相似文献   

12.
《Solid State Sciences》2012,14(5):616-621
Titanium dioxide mesoporous microspheres with high surface area was successfully prepared by a facile one-step hydrothermal approach using polyethylene glycol (PEG, MW 200) as the soft template. Study shows that ∼15 nm TiO2 nanoparticles was assembled into ∼1.1 μm mesoporous microspheres. The Brunauer-Emmett-Teller surface area of TiO2 microsphere is up to 137 m2/g. TiO2 mesoporous microspheres were fabricated onto the surface of fluorine-doped tin oxide glass and used as the photoanode of dye-sensitized solar cells, which exhibits an open circuit photovoltage of 0.80 V and an overall conversion efficiency of 6.6%. Owing to the enhanced dye loading and light-harvesting efficiency, a 26% improvement in the overall conversion efficiency was achieved when compared with the commercial Degussa P25 nanoparticles.  相似文献   

13.
以埃洛石纳米管(HNTs)为模板和聚乙烯醇(PVA)为碳源,采用水热纳米浇筑法成功制备出碳纳米棒。方法涉及3步,即在HNTs中浇筑PVA,碳化和模板移除。采用一系列表征手段如XRD、FT-IR、SEM、TEM、Raman、XPS、SAED和N2吸附-脱附等表征碳纳米棒的形成和结构。具有一维棒状结构的碳纳米棒具有高的比表面积(408 m2·g-1)和典型的介孔特征。  相似文献   

14.
《化学:亚洲杂志》2017,12(22):2956-2961
Developing efficient non‐noble metal and earth‐abundant electrocatalysts with tunable microstructures for overall water splitting is critical to promote clean energy technologies for a hydrogen economy. Herein, novel three‐dimensional (3D) flower‐like Ni2P composed of mesoporous nanoplates with controllable morphology and high surface area was prepared by a hydrothermal method and low‐temperature phosphidation as efficient electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Compared with the urchin‐like Nix Py , the 3D flower‐like Ni2P with a diameter of 5 μm presented an efficient and stable catalytic performance in 0.5 m H2SO4, with a small Tafel slope of 79 mV dec−1 and an overpotential of about 240 mV at a current density of 10 mA cm−2 with a mass loading density of 0.283 mg cm−2. In addition, the catalyst also exhibited a remarkable performance for the OER in 1.0 m KOH electrolyte, with an overpotential of 320 mV to reach a current density of 10 mA cm−2 and a small Tafel slope of 72 mV dec−1. The excellent catalytic performance of the as‐prepared Ni2P may be ascribed to its novel 3D morphology with unique mesoporous structure.  相似文献   

15.
许晓颖  孔岩  陈玉  赵南  时晓波  王军 《无机化学学报》2012,28(11):2478-2484
活性金属掺杂的具有三维立方孔道结构的MCM-48在芳烃的氧化反应具有潜在应用价值。使用乙醇做助溶剂,在低的模板剂浓度下,经过一步水热法首次合成了球形的V-MCM-48。通过XRD,场发射扫描电镜,氮气吸附-脱附,红外,拉曼,核磁,X射线光电子能谱和ICP等技术对样品进行了表征。结果表明这些样品具有大的比表面积(1 005 m2.g),有序的孔道结构。当V/Si的物质的量比高达2.91%时,仍没有出现V2O5晶体。大部分的钒进入了硅的骨架。所合成材料在低温过氧化氢直接氧化苯乙烯的反应中表现出良好的催化性能。  相似文献   

16.
刘时铸  孙丰强 《无机化学学报》2010,26(12):2215-2220
利用螯合剂乙二胺四乙酸二钠(EDTA-Na2)作为致孔剂,以三氯化钛(TiCl3)为前驱体,利用水热法直接合成了氮掺杂的纳米多孔TiO2。通过 SEM、XRD、IR、低温N2吸附-脱附、XPS、热重分析(TG)和紫外可见(UV)光谱对样品进行了表征与分析。结果表明所合成TiO2以锐钛矿相形式存在,氮掺在TiO2晶面之间,具有典型的介孔结构和较高的比表面积,通过改变EDTA-Na2的浓度,比表面积可控制在95~216 m2·g-1之间。这种纳米多孔TiO2在光降解甲基橙的实验中表现出很好的光催化活性,且随着EDTA-Na2的浓度增大而逐渐增加。  相似文献   

17.
以埃洛石纳米管(HNTs)为模板和聚乙烯醇(PVA)为碳源,采用水热纳米浇筑法成功制备出碳纳米棒。方法涉及3步,即在HNTs中浇筑PVA,碳化和模板移除。采用一系列表征手段如XRD、FT-IR、SEM、TEM、Raman、XPS、SAED和N2吸附-脱附等表征碳纳米棒的形成和结构。具有一维棒状结构的碳纳米棒具有高的比表面积(409 m2·g-1)和典型的介孔特征。  相似文献   

18.
Anatase phase mesoporous TiO2 with I41/amd space group was synthesized via the urea assisted hydrothermal method. The existence of mono phasic TiO2 sub-microspheres of uniform particle size (ca. 400 nm) encompassing an average crystallite size of 14 nm was demonstrated using the XRD, FE-SEM and TEM analysis. Surface area of ca. 116.49 m2/g along with a pore size of 7 nm was calculated using the BET and adsorption isotherm measurements which authenticated the mesoporous nature of the synthesized material. Suitable calcination temperature for the better electrochemical property was established via the optimization process. Accordingly, the mesoporous TiO2 calcined at 400 °C displayed improved cycleability with excellent rate capability ever reported, even at 20 C-rate of discharge. The reason for the superior rate capability is corroborated to the highly mesoporous nature of the TiO2 sub-microspheres that has imparted desirable surface area apposite for enhanced ionic and electronic diffusion.  相似文献   

19.
Using tetraethylorthosilicate (TEOS), polymethylhydrosiloxane (PMHS) and aluminium isopropoxide (AIP) as the reactants, through a one-step nonsurfactant route based on PMHS-TEOS-AIP co-polycondensation, hydrothermally stable mesoporous aluminosilicates with different Si/Al molar ratios were successfully prepared. All samples exclusively showed narrow pore size distribution centered at 3.6 nm. To assess the hydrothermal stability, samples were subjected to 100 °C distilled water for 300 h. The boiled mesoporous aluminosilicates have nearly the same N2 adsorption-desorption isotherms and the same pore size distributions as those newly synthesized ones, indicating excellent hydrothermal stability. The 29Si MAS NMR spectra confirmed that PMHS and TEOS have jointly condensed and CH3 groups have been introduced into the materials. The 27Al MAS NMR spectra indicated that Al atoms have been incorporated in the mesopore frameworks. The NH3 temperature-programmed desorption showed strong acidity. Due to the existence of large amount of CH3 groups, the mesoporous aluminosilicates obtained good hydrophobicity. Owing to the relatively large pore and the strong acidity provided by the uniform four-coordinated Al atoms, the excellent catalytic performance for 1,3,5-triisopropylbenzene cracking was acquired easily. The materials may be a profitable complement for the synthesis of solid acid catalysts.  相似文献   

20.
Large-sized, optical transparent mesostructured Brij 56/silica monolith has been fabricated using a lyotropic liquid crystal of Brij 56 (C16EO10) as a template and TMOS as a silica source, combined with a optimizing sol-gel process and a hydrothermal aging process. By programmed temperature drying and calcinations, translucent mesoporous silica monolith with two-dimensional hexagonal structure (P6mm) has bee obtained. The ordered mesoporous silica monoliths have been characterized by small-angle X-ray diffraction, transmission electron microscopy (TEM), and nitrogen adsorption, which shows that the materials have a highly ordered two-dimensional hexagonal mesostructure with the high specific surface area of 837 m2 · g−1 and narrow pore distribution with a mean BJH pore diameter of 2.73 nm. Based on calculations and differential scanning calorimetry and thermogravimetric analyses, the action mechanism of the hydrothermal aging process has been proposed: the 100°C hydrothermal conditions and autogenous 2.3 atm pressure promote the condensation and dehydration of silanol groups, with the result that cross-linking degree, the flaws and moisture content in gels are reduced notably. Those processes guarantee the integrity of gels in the following drying process.  相似文献   

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