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1.
Visible‐light‐driven plasmonic photocatalyst Ag‐TiO2 nanocomposite hollow spheres are prepared by a template‐free chemically‐induced self‐transformation strategy under microwave‐hydrothermal conditions, followed by a photochemical reduction process under xenon lamp irradiation. The prepared samples are characterized by using scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, N2 adsorption‐desorption isotherms, X‐ray photoelectron spectroscopy, UV/Vis and Raman spectroscopy. Production of ?OH radicals on the surface of visible‐light illuminated TiO2 was detected by using a photoluminescence method with terephthalic acid as the probe molecule. The photocatalytic activity of as‐prepared samples was evaluated by photocatalytic decolorization of Rhodamine B (RhB) aqueous solution at ambient temperature under visible‐light irradiation. The results show that the surface plasmon absorption band of the silver nanoparticles supported on the TiO2 hollow spheres was red shifted, and a strong surface enhanced Raman scattering effect for the Ag‐TiO2 nanocomposite sample was observed. The prepared nanocomposite hollow spheres exhibits a highly visible‐light photocatalytic activity for photocatalytic degradation of RhB in water, and their photocatalytic activity is higher than that of pure TiO2 and commercial Degussa P25 (P25) powders. Especially, the as‐prepared Ag‐TiO2 nanocomposite hollow spheres at the nominal atomic ratio of silver to titanium ( R ) of 2 showed the highest photocatalytic activity, which exceeds that of P25 by a factor of more than 2. 相似文献
2.
Min Qiao Qiang Chen Shishan Wu Jian Shen 《Journal of Sol-Gel Science and Technology》2010,55(3):377-384
Novel ammonia and triethanolamine assisted sol–gel synthesis method was developed to fabricate the N-doped TiO2 hollow spheres. The prepared hollow spheres were in submicron size and had good morphology and high specific surface area.
Polystyrene (PS) latexes in size of 470 nm were used as the templates to fabricate PS/TiO2 core–shell spheres. Here ammonia and triethanolamine was first employed together to control the sol–gel process. The N-doped
TiO2 hollow spheres were got after calcinations of the core–shell spheres by using triethanolamine as N source, and the amount
of doped N could be easily adjusted by changing the amount of triethanolamine. The hollow spheres had distinct visible light
response, and the optical response shifted more to the visible region as the amount of doped N increases. The photodegradation
of methylene blue expressed the high photocatalytic activity of the N-doped TiO2 hollow spheres under visible light. 相似文献
3.
Production of Hydrogen by Glycerol Photoreforming Using Binary Nitrogen–Metal‐Promoted N‐M‐TiO2 Photocatalysts
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The need for renewable energy focuses attention on hydrogen obtained by using sustainable and green methods. The sustainable compound glycerol can be used for hydrogen production by heterogeneous photocatalysis. A novel approach involves the promotion of the TiO2 photocatalyst with a binary combination of nitrogen and transition metal. We report the synthesis and spectroscopic characterization of the new N‐M‐TiO2 photocatalysts (M=none, Cr, Co, Ni, Cu), and the photocatalytic reforming of glycerol to hydrogen under ambient conditions and near‐UV or visible light versus benchmark P25 TiO2. In units of activity μmol m?2 h?1, N‐Ni‐TiO2 is five‐fold more active than P25, and N‐Cu‐TiO2 is 44‐fold more active. The photocatalytic activity of N‐M‐TiO2 increases from Cr to Co and Ni, whereas the photoluminescence decreases; the change in activity is due to the modulation of charge recombination. 相似文献
4.
Synthesis of Hollow Mesoporous TiO2 Microspheres with Single and Double Au Nanoparticle Layers for Enhanced Visible‐Light Photocatalysis
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Dr. Zia Ur Rahman Dr. Ning Wei Dr. Yange Feng Dr. Xiaolong Zhang Prof. Daoai Wang 《化学:亚洲杂志》2018,13(4):432-439
A facile method was used to prepare hollow mesoporous TiO2 and Au@TiO2 spheres using polystyrene (PS) templates. Au nanoparticles (NPs) were simultaneously synthesized and attached on the surface of PS spheres by reducing AuCl4? ions using sodium citrate which resulted in the uniform deposition of Au NPs. The outer coating of titania via sol‐gel produced PS@Au@TiO2 core–shell spheres. Removing the templates from these core–shell spheres through calcination produced hollow mesoporous and crystalline Au@TiO2 spheres with Au NPs inside the TiO2 shell in a single step. Anatase spheres with double Au NPs layers, one inside and another outside of TiO2 shell, were also prepared. Different characterization techniques indicated the hollow mesoporous and crystalline morphology of the prepared spheres with Au NPs. Hollow anatase spheres with Au NPs indicated enhanced harvesting of visible light and therefore demonstrated efficient catalytic activity toward the degradation of organic dyes under the irradiation of visible light as compared to bare TiO2 spheres. 相似文献
5.
《化学:亚洲杂志》2017,12(22):2942-2949
Hollow hybrid nanostructures have received significant attention because of their unique structural features. This study reports a facile ion adsorption–heating method to fabricate hollow PbS‐TiO2 hybrid particles. In this method, the TiO2 spheres used as a substrate material to grow PbS are aggregates of many small amorphous TiO2 particles, and each small particle is covered with thioglycolic acid ligands through Ti4+–carboxyl coordination. When Pb2+ ions are added to a colloidal solution of these TiO2 spheres, these ions are adsorbed by sulfhydryl (‐SH) groups to form metal thiolates, and the C−S bond is dissociated by heating to release S2−. The S2− ions react with Pb2+ ions to form PbS without additive sulfur sources. Additionally, the amorphous TiO2 spheres are transformed into the anatase phase during the heating process. As a result, the crystallization of TiO2 spheres along with the formation of PbS is simultaneously carried out by heating. During the heating process, owing to the Kirkendall effect of S2− diffusion and the Ostwald ripening effect of the crystallization of amorphous TiO2 spheres, PbS‐TiO2 hollow hybrid structures can be obtained. The XRD and XPS characterizations proved the formation of anatase TiO2 and PbS. The TEM characterization confirmed the formation of hollow structures in the PbS‐TiO2 hybrid sample. The photocatalytic activity of the hollow PbS‐TiO2 hybrid spheres have been investigated for the degradation of Cr6+ under visible light. The results show that hollow PbS‐TiO2 hybrid spheres exhibited the highest photocatalytic activity, in which almost all the Cr6+ was degraded after 140 min. 相似文献
6.
Three‐Dimensional Ordered Assembly of Thin‐Shell Au/TiO2 Hollow Nanospheres for Enhanced Visible‐Light‐Driven Photocatalysis
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Cao‐Thang Dinh Hoang Yen Prof. Freddy Kleitz Prof. Trong‐On Do 《Angewandte Chemie (International ed. in English)》2014,53(26):6618-6623
An Au/TiO2 nanostructure was constructed to obtain a highly efficient visible‐light‐driven photocatalyst. The design was based on a three‐dimensional ordered assembly of thin‐shell Au/TiO2 hollow nanospheres (Au/TiO2‐3 DHNSs). The designed photocatalysts exhibit not only a very high surface area but also photonic behavior and multiple light scattering, which significantly enhances visible‐light absorption. Thus Au/TiO2‐3 DHNSs exhibit a visible‐light‐driven photocatalytic activity that is several times higher than conventional Au/TiO2 nanopowders. 相似文献
7.
Jiaguo Yu Qin Li Shengwei Liu Mietek Jaroniec 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(7):2433-2441
Exploiting advanced photocatalysts under visible light is of primary significance for the development of environmentally relevant photocatalytic decontamination processes. In this study, the ionic liquid (IL), 1‐butyl‐3‐methylimidazolium tetrafluoroborate, was employed for the first time as both a structure‐directing agent and a dopant for the synthesis of novel fluorinated B/C‐codoped anatase TiO2 nanocrystals (TIL) through hydrothermal hydrolysis of tetrabutyl titanate. These TIL nanocrystals feature uniform crystallite and pore sizes and are stable with respect to phase transitions, crystal ripening, and pore collapse upon calcination treatment. More significantly, these nanocrystals possess abundant localized states and strong visible‐light absorption in a wide range of wavelengths. Because of synergic interactions between titania and codopants, the calcined TIL samples exhibited high visible‐light photocatalytic activity in the presence of oxidizing Rhodamine B (RhB). In particular, 300 °C‐calcined TIL was most photocatalytically active; its activity was much higher than that of TiO1.98N0.02 and reference samples (TW) obtained under identical conditions in the absence of ionic liquid. Furthermore, the possible photocatalytic oxidation mechanism and the active species involved in the RhB degradation photocatalyzed by the TIL samples were primarily investigated experimentally by using different scavengers. It was found that both holes and electrons, as well as their derived active species, such as .OH, contributed to the RhB degradation occurring on the fluorinated B/C‐codoped TiO2 photocatalyst, in terms of both the photocatalytic reaction dynamics and the reaction pathway. The synthesis of the aforementioned novel photocatalyst and the identification of specific active species involved in the photodegradation of dyes could shed new light on the design and synthesis of semiconductor materials with enhanced photocatalytic activity towards organic pollutants. 相似文献
8.
Yiseul Park N. Jiten Singh Dr. Kwang S. Kim Prof. Dr. Takashi Tachikawa Dr. Tetsuro Majima Prof. Dr. Wonyong Choi Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(41):10843-10850
The development of visible‐light‐active photocatalysts is being investigated through various approaches. In this study, C60‐based sensitized photocatalysis that works through the charge transfer (CT) mechanism is proposed and tested as a new approach. By employing the water‐soluble fullerol (C60(OH)x) instead of C60, we demonstrate that the adsorbed fullerol activates TiO2 under visible‐light irradiation through the “surface–complex CT” mechanism, which is largely absent in the C60/TiO2 system. Although fullerene and its derivatives have often been utilized in TiO2‐based photochemical conversion systems as an electron transfer relay, their successful photocatalytic application as a visible‐light sensitizer of TiO2 is not well established. Fullerol/TiO2 exhibits marked visible photocatalytic activity not only for the redox conversion of 4‐chlorophenol, I?, and CrVI, but also for H2 production. The photoelectrode of fullerol/TiO2 also generates an enhanced anodic photocurrent under visible light as compared with the electrodes of bare TiO2 and C60/TiO2, which confirms that the visible‐light‐induced electron transfer from fullerol to TiO2 is particularly enhanced. The surface complexation of fullerol/TiO2 induced a visible absorption band around 400–500 nm, which was extinguished when the adsorption of fullerol was inhibited by fluorination of the surface of TiO2. The transient absorption spectroscopic measurement gave an absorption spectrum ascribed to fullerol radical cations (fullerol.+) the generation of which should be accompanied by the proposed CT. The theoretical calculation regarding the absorption spectra for the (TiO2 cluster+fullerol) model also confirmed the proposed CT, which involves excitation from HOMO (fullerol) to LUMO (TiO2 cluster) as the origin of the visible‐light absorption. 相似文献
9.
Visible‐light‐driven self‐cleaning SERS substrate of silver nanoparticles and graphene oxide decorated nitrogen‐doped titania nanotube array
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Graphene oxide (GO) and silver nanoparticles (Ag NPs) sequentially decorated nitrogen‐doped titania nanotube array (N‐TiO2 NTA) had been designed as visible‐light‐driven self‐cleaning surface‐enhanced Raman scattering (SERS) substrate for a recyclable SERS detection application. N‐TiO2 NTA was fabricated by anodic oxidation and then doping nitrogen treatment in ammonia atmosphere, acting as a visible‐light‐driven photocatalyst and supporting substrate. Ag/GO/N‐TiO2 NTA was prepared by decorating GO monolayer through an impregnation process and then depositing Ag NPs through a polyol process on the surface of N‐TiO2 NTA, acting as the collection of organic molecule and Raman enhancement. The SERS activity of Ag/GO/N‐TiO2 NTA was evaluated using methyl blue as an organic probe molecule, revealing the analytical enhancement factor of 4.54 × 104. Ag/GO/N‐TiO2 NTA was applied as active SERS substrate to determine a low‐affinity organic pollutant of bisphenol A, revealing the detection limit of as low as 5 × 10?7 m . Ag/GO/N‐TiO2 NTA could also achieve self‐cleaning function for a recycling utilization through visible‐light‐driven photocatalytic degradation of the adsorbed organic molecules. Ag/GO/N‐TiO2 NTA has been successfully reused for five times without an obvious decay in accuracy and sensitivity for organic molecule detection. The unique properties of this SERS substrate enable it to have a promising application for the sensitive and recyclable SERS detection of low‐affinity organic molecules. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
10.
Visible Light Photocatalytic Activity of Pt/N‐TiO2 towards Enhanced H2 Production from Water Splitting
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Present work mainly focuses on experimental investigation to improvement of hydrogen production by water photoelectrolysis. An experimental facility was designed and constructed for visible light photocatalysis. A series of N‐TiO2 photocatalysts impregnated with platinum on the surface of N‐TiO2 were prepared. Hydrogen production upon irradiating aqueous Pt/N‐TiO2 suspension with visible light was investigated. The shift in excitation wavelength of TiO2 was 380 nm improved the yield of hydrogen production by N‐TiO2 and Pt/N‐TiO2. We used a 400 W mercury arc lamp combined with a 400 nm cutoff filter eliminating all the wavelengths under 400 nm. Pt/N‐TiO2 material was characterized with TPR, reflective UV/Visible spectroscopy and TEM. The best hydrogen production rate obtained for this setup for N/Ti = 10, 0.05 wt% Pt/N‐TiO2, through water splitting was about 772 μmolh?1g?1. 相似文献
11.
Highly Efficient Low‐Temperature Plasma‐Assisted Modification of TiO2 Nanosheets with Exposed {001} Facets for Enhanced Visible‐Light Photocatalytic Activity
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Beibei Li Prof. Zongbin Zhao Quan Zhou Bo Meng Xiangtong Meng Prof. Jieshan Qiu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14763-14770
Anatase TiO2 nanosheets with exposed {001} facets have been controllably modified under non‐thermal dielectric barrier discharge (DBD) plasma with various working gas, including Ar, H2, and NH3. The obtained TiO2 nanosheets possess a unique crystalline core/amorphous shell structure (TiO2@TiO2?x), which exhibit the improved visible and near‐infrared light absorption. The types of dopants (oxygen vacancy/surface Ti3+/substituted N) in oxygen‐deficient TiO2 can be tuned by controlling the working gases during plasma discharge. Both surface Ti3+ and substituted N were doped into the lattice of TiO2 through NH3 plasma discharge, whereas the oxygen vacancy or Ti3+ (along with the oxygen vacancy) was obtained after Ar or H2 plasma treatment. The TiO2@TiO2?x from NH3 plasma with a green color shows the highest photocatalytic activity under visible‐light irradiation compared with the products from Ar plasma or H2 plasma due to the synergistic effect of reduction and simultaneous nitridation in the NH3 plasma. 相似文献
12.
Dr. Zhanfeng Zheng Jian Zhao Dr. Yong Yuan Dr. Hongwei Liu Dr. Dongjiang Yang Sarina Sarina Prof. Hongjie Zhang Dr. Eric R. Waclawika Prof. Huaiyong Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(18):5731-5741
Nitrogen‐doped TiO2 nanofibres of anatase and TiO2(B) phases were synthesised by a reaction between titanate nanofibres of a layered structure and gaseous NH3 at 400–700 °C, following a different mechanism than that for the direct nitrogen doping from TiO2. The surface of the N‐doped TiO2 nanofibres can be tuned by facial calcination in air to remove the surface‐bonded N species, whereas the core remains N doped. N‐Doped TiO2 nanofibres, only after calcination in air, became effective photocatalysts for the decomposition of sulforhodamine B under visible‐light irradiation. The surface‐oxidised surface layer was proven to be very effective for organic molecule adsorption, and the activation of oxygen molecules, whereas the remaining N‐doped interior of the fibres strongly absorbed visible light, resulting in the generation of electrons and holes. The N‐doped nanofibres were also used as supports of gold nanoparticle (Au NP) photocatalysts for visible‐light‐driven hydroamination of phenylacetylene with aniline. Phenylacetylene was activated on the N‐doped surface of the nanofibres and aniline on the Au NPs. The Au NPs adsorbed on N‐doped TiO2(B) nanofibres exhibited much better conversion (80 % of phenylacetylene) than when adsorbed on undoped fibres (46 %) at 40 °C and 95 % of the product is the desired imine. The surface N species can prevent the adsorption of O2 that is unfavourable for the hydroamination reaction, and thus, improve the photocatalytic activity. Removal of the surface N species resulted in a sharp decrease of the photocatalytic activity. These photocatalysts are feasible for practical applications, because they can be easily dispersed into solution and separated from a liquid by filtration, sedimentation or centrifugation due to their fibril morphology. 相似文献
13.
Visible‐Light‐Induced Electron Transport from Small to Large Nanoparticles in Bimodal Gold Nanoparticle‐Loaded Titanium(IV) Oxide
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Dr. Shin‐ichi Naya Tadahiro Niwa Takahiro Kume Prof. Dr. Hiroaki Tada 《Angewandte Chemie (International ed. in English)》2014,53(28):7305-7309
A key to realizing the sustainable society is to develop highly active photocatalysts for selective organic synthesis effectively using sunlight as the energy source. Recently, metal‐oxide‐supported gold nanoparticles (NPs) have emerged as a new type of visible‐light photocatalysts driven by the excitation of localized surface plasmon resonance of Au NPs. Here we show that visible‐light irradiation (λ>430 nm) of TiO2‐supported Au NPs with a bimodal size distribution (BM‐Au/TiO2) gives rise to the long‐range (>40 nm) electron transport from about 14 small (ca. 2 nm) Au NPs to one large (ca. 9 nm) Au NP through the conduction band of TiO2. As a result of the enhancement of charge separation, BM‐Au/TiO2 exhibits a high level of visible‐light activity for the one‐step synthesis of azobenzenes from nitrobenzenes at 25 °C with a yield greater than 95 % and a selectivity greater than 99 %, whereas unimodal Au/TiO2 (UM‐Au/TiO2) is photocatalytically inactive. 相似文献
14.
Template‐free Fabrication of Hierarchical Macro‐/mesoporous N‐doped TiO2/graphene Oxide Composites with Enhanced Visible‐light Photocatalytic Activity
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Hierarchical macro‐/mesoporous N‐doped TiO2/graphene oxide (N‐TiO2/GO) composites were prepared without using templates by the simple dropwise addition mixed solution of tetrabutyl titanate and ethanol containg graphene oxide (GO) to the ammonia solution, and then calcined at 350 °C. The as‐prepared samples were characterized by scanning electron microscopy (SEM), Brunauer‐Emmett‐Teller (BET) surface area, X‐ray diffraction (XRD), Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), and UV‐Vis absorption spectroscopy. The photocatalytic activity was evaluated by the photocatalytic degradation of methyl orange in an aqueous solution under visible‐light irradiation. The results show that N‐TiO2/GO composites exhibited enhanced photocatalytic activity. GO content exhibited an obvious influence on photocatalytic performance, and the optimal GO addition content was 1 wt%. The enhanced photocatalytic activity could be attributed to the synergetic effects of three factors including the improved visible light absorption, the hierarchical macro‐mesoporous structure, and the efficient charge separation by GO. 相似文献
15.
Nitrogen-doped TiO2 nanoparticle photocatalysts were obtained by an annealing method with gaseous ammonia and nitrogen. The influence of dopant N on the crystal structure was characterized by XRD, XPS, BET, TEM and UV-Vis spectra. The results of XRD indicate that, the crystal phase transforms from anatase to rutile structure gradually with increase of annealing temperature from 300 to 700 ℃. XPS studies indicate that the nitrogen atom enters the TiO2 lattice and occupies the position of oxygen atom. Agglomeration of particles is found in TEM images after annealing. BET results show that the specific surface areas of N-doped samples from 44.61 to 38.27 m2/g are smaller than that of Degussa TiO2. UV-Vis spectra indicate that the absorption threshold shifts gradually with increase of annealing temperature, which shows absorption in the visible region. The influence of annealing condition on the photocatalytic property has been researched over water decomposition to hydrogen, indicating that nitrogen raises the photocatalytic activity for hydrogen evolution, and the modified TiO2 annealed for 2 h at 400 ℃ under gas of NH3/N2 (V/V=1/2) mixture shows better efficiency of hydrogen evolution. Furthermore, the N-doped TiO2 nanoparticle catalysts have obvious visible light activity, evidenced by hydrogen evolution under visible light (λ>400 nm) irradiation. However, the catalytic activity under visible light irradiation is absent for Degussa as reference and the N-doped TiO2 annealed at 700 ℃. 相似文献
16.
Self‐Templated Formation of Uniform NiCo2O4 Hollow Spheres with Complex Interior Structures for Lithium‐Ion Batteries and Supercapacitors
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Laifa Shen Le Yu Dr. Xin‐Yao Yu Prof. Xiaogang Zhang Prof. Xiong Wen Lou 《Angewandte Chemie (International ed. in English)》2015,54(6):1868-1872
Despite the significant advancement in preparing metal oxide hollow structures, most approaches rely on template‐based multistep procedures for tailoring the interior structure. In this work, we develop a new generally applicable strategy toward the synthesis of mixed‐metal‐oxide complex hollow spheres. Starting with metal glycerate solid spheres, we show that subsequent thermal annealing in air leads to the formation of complex hollow spheres of the resulting metal oxide. We demonstrate the concept by synthesizing highly uniform NiCo2O4 hollow spheres with a complex interior structure. With the small primary building nanoparticles, high structural integrity, complex interior architectures, and enlarged surface area, these unique NiCo2O4 hollow spheres exhibit superior electrochemical performances as advanced electrode materials for both lithium‐ion batteries and supercapacitors. This approach can be an efficient self‐templated strategy for the preparation of mixed‐metal‐oxide hollow spheres with complex interior structures and functionalities. 相似文献
17.
Dr. Jingjing Xie Prof. Hao Xie Prof. Bao‐Lian Su Prof. Yi‐bing Cheng Prof. Xiaodong Du Dr. Hui Zeng Dr. Menghu Wang Prof. Weimin Wang Prof. Hao Wang Prof. Zhengyi Fu 《Angewandte Chemie (International ed. in English)》2016,55(9):3031-3035
Structure‐forming processes leading to biominerals are well worth learning in pursuit of new synthetic techniques. Strategies that attempt to mimic nature in vitro cannot replace an entire complex natural organism, requiring ingenuity beyond chemists′ hands. A “bioprocess‐inspired synthesis” is demonstrated for fabrication of N‐doped TiO2 materials at ambient temperature by direct implantation of precursor into living mussels. The amorphous precursor transforms into N‐doped anatase TiO2 with a hierarchical nanostructure. Synthetic TiO2 exhibits high phase stability and enhanced visible‐light photocatalytic activity as a result of modifications to its band gap during in vivo mineralization. Intracellular proteins were found to be involved in TiO2 mineralization. Our findings may inspire material production by new synthetic techniques, especially under environmentally benign conditions. 相似文献
18.
Chia‐Fen Lee Mei‐Ling Lin Yu‐Cheng Wang Wen‐Yen Chiu 《Journal of polymer science. Part A, Polymer chemistry》2012,50(13):2626-2634
In this study, the poly(NIPAAm–MAA)/Fe3O4 hollow latex particles were synthesized by three steps. The first step was to synthesize the poly(methyl methacrylate‐co‐methylacrylate acid) (poly(MMA‐MAA)) copolymer latex particles by the method of soapless emulsion polymerization. Following the first step, the second step was to polymerize N‐isopropylacrylamide (NIPAAm), MAA, and crosslinking agent (N,N'‐methylene‐bisacrylamide (MBA)) in the presence of poly(MMA‐MAA) latex particles to form the linear poly(MMA‐MAA)/crosslinking poly (NIPAAm‐MAA) core‐shell latex particles. After the previous processes, the core‐shell latex particles were heated in the presence of NH4OH to dissolve the linear poly(MMA‐MAA) core in order to form the poly(NIPAAm‐MAA) hollow latex particles. In the third step, Fe2+ and Fe3+ ions were introduced to bond with the ? COOH groups of MAA segments in the poly(NIPAAm‐MAA) hollow polymer latex particles. Further by a reaction with NH4OH and then Fe3O4 nanoparticles were generated in situ and the poly(NIPAAm‐MAA)/Fe3O4 magnetic composite hollow latex particles were formed. The concentrations of MAA, crosslinking agent (N,N'‐methylene bisacrylamide), and Fe3O4 nanoparticles were important factors to influence the morphology of hollow latex particles and lower critical solution temperature of poly(NIPAAm–MAA)/Fe3O4 magnetic composite hollow latex particles. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
19.
Dr. Yuming Chen Dr. Xiaoyan Li Dr. Kyusung Park Prof. Limin Zhou Prof. Haitao Huang Prof. Yiu‐Wing Mai Prof. John B. Goodenough 《Angewandte Chemie (International ed. in English)》2016,55(51):15831-15834
Low‐cost, single‐step synthesis of hollow nanotubes of N‐doped carbon deposited on CoS is enabled by the simultaneous use of three functionalities of polyacrylonitrite (PAN) nanofibers: 1) a substrate for loading active materials, 2) a sacrificial template for creating hollow tubular structures, and 3) a precursor for in situ nitrogen doping. The N‐doped carbon in hollow tubes of CoS provides a high‐capacity anode of long cycle life for a rechargeable Li‐ion or Na‐ion battery cell that undergoes the conversion reaction 2 A++2 e?+CoS →Co+A2S with A=Li or Na. 相似文献
20.
Photocatalytic Degradation of Glyphosate in Water by N‐Doped SnO2/TiO2 Thin‐Film‐Coated Glass Fibers
Peerawas Kongsong Lek Sikong Sutham Niyomwas Vishnu Rachpech 《Photochemistry and photobiology》2014,90(6):1243-1250
Photocatalytic degradation of glyphosate contaminated in water was investigated. The N‐doped SnO2/TiO2 films were prepared via sol–gel method, and coated on glass fibers by dipping method. The effects of nitrogen doping on coating morphology, physical properties and glyphosate degradation rates were experimentally determined. Main variable was the concentration of nitrogen doping in range 0–40 mol%. Nitrogen doping results in shifting the absorption wavelengths and narrowing the band gap energy those lead to enhancement of photocatalytic performance. The near optimal 20N/SnO2/TiO2 composite thin film exhibited about two‐ and four‐folds of glyphosate degradation rates compared to the undoped SnO2/TiO2 and TiO2 films when photocatalytic treatment were performed under UV and solar irradiations, respectively, due to its narrowest band gap energy (optical absorption wavelength shifting to visible light region) and smallest crystallite size influenced by N‐doping. 相似文献