CRYSTENGCOMM
·
2016
·Vol. 18
·期 10
·1847-1853
·
IF 3.849
Jun-Qiang Bai,Wei Wen,Jin-Ming Wu
Because of the high specific surface area and enhanced charge migration, TiO2 with unique belt-like nanostructures finds promising applications in various fields such as photocatalysis, dye-sensitized solar cells, gas sensors, and Li-ion batteries. In the current study, a solution combustion procedure was firstly adopted to prepare a black water-proof precursor. The black precursor interacted with H2O2 at ambient temperature, achieving a precursor solution that is capable of fabricating hydrogen titanate (H2Ti2O5·H2O) nanobelt arrays on metallic Ti substrates at 60 °C. Subsequent calcination in air at 400 °C achieved arrays of ultrathin anatase TiO2 nanobelts of ca. 2–4 nm in thickness. The addition of nickel nitrate in the combustion solution achieved the Ni-doping into the resultant TiO2 nanobelts, which did not alter the nanobelt structure but significantly reduced the band gap from 3.2 eV to 2.9 eV. When compared with the commonly alkali-hydrothermal synthesized anatase TiO2 nanobelts, the present ultrathin nanobelts exhibited much improved photocatalytic activity when utilized to assist photodegradation of rhodamine B in water. The ultrathin nanobelt structure is believed to contribute to the high specific surface area, the much reduced charge migration path, and the enhanced charge transport along the longitudinal direction. The appropriate Ni-doping further enhanced the photocatalytic performance, because of the increased light harvesting efficiency and reduced charge recombination.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
CRYSTENGCOMM
·
2020
·Vol. 22
·期 23
·4030-4038
·
IF 3.117
Jin Yan,Lei Dai,Penghui Shi,Jinchen Fan,Yulin Min,Qunjie Xu
A limited light absorption range and low electron transfer efficiency have always been the major problems in semiconductor photocatalysis. Here, a defect-rich heterophase junction-containing TiO2 porous nanostructure was designed and synthesized to improve the low utilization rate of photoexcited carriers in photocatalysis. Defects were first introduced into titanium dioxide, and co-doping was used to obtain defect-rich materials. At the same time, heterophase junction TiO2 with anatase and rutile phases was obtained under temperature control. The TiO2 phase junction could significantly improve the interface charge recombination. These two synergistically regulated the hydrogen production favorably, thus improving the carrier separation efficiency and reducing the band gap from the ultraviolet to the visible region, which resulted in the construction of the most effective defects. Theoretical predictions and empirical characterizations indicate that TiO2 with defects introduced into it presents a porous structure, and the doped phase exposes the internal defects of the bulk phase of the material to the surface and adjusts the defect position. The experimental results confirmed that the synergistic effect of B and Rh co-doping increased the photocatalytic hydrogen production yield of TiO2 by 10 times. This study provides new insights into photocatalyst defect regulation.
研究领域:
材料科学
·
纳米技术
·
能源化学
·
光催化
·
半导体物理
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Benyong Yang,Wentao Mu,Benedict Tsz Woon Lo,Sijie Liu,Zhihang Chen,Liam John France,Xuehui Li
NOx and CO formation is, at present, a consequence arising from fuel production, but their emission need not be. In this study, a series of novel Ir-containing TiO2-nanobelt catalysts were designed and prepared for the simultaneous removal of NOx and CO. Activity data demonstrates that the TiO2(B) support promotes NO reduction compared to anatase. Furthermore, reaction efficiency (RE), a measure of NOx consumption vis-à-vis that of CO, reveals that catalysts containing anatase promote CO oxidation more so than their TiO2(B) counterparts. Increasing Ir concentration over the latter promotes low-temperature catalytic performance, an effect believed to be linked to the formation of Ir0–IrO2 composites. In situ DRIFTS experiments reveal the relevance of nitrite/nitrate formation and consumption at 250 °C, a mechanism insinuated by the RE value. However, at 300 °C, both TOF and RE increase, signifying the participation of a faster and more-selective reaction, which appears consistent with the isocyanate-mediated pathway.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2020
·Vol. 25
·期 9
·2109
·
IF 3.267
Changzhou Chen,Peng Liu,Haihong Xia,Minghao Zhou,Jiaping Zhao,Brajendra K. Sharma,Jianchun Jiang
It is of great importance to explore the selective hydrogenolysis of β-O-4 linkages, which account for 45–60% of all linkages in native lignin, to produce valued-added chemicals and fuels from biomass employing UV light as catalyst. TiO2exhibited satisfactory catalytic performances in various photochemical reactions, due to its versatile advantages involving high catalytic activity, low cost and non-toxicity. In this work, 20 wt.% Ni/TiO2and oxidant PCC (Pyridinium chlorochromate) were employed to promote the cleavage of β-O-4 alcohol to obtain high value chemicals under UV irradiation at room temperature. The Ni/TiO2photocatalyst can be magnetically recovered and efficiently reused in the following four consecutive recycling tests in the cleavage of β-O-4 ether bond in lignin. Mechanism studies suggested that the oxidation of β-O-4 alcohol to β-O-4 ketone by oxidant PCC first occurred during the reaction, and was followed by the photocatalysis of the obtained β-O-4 ketone to corresponding acetophenone and phenol derivates. Furthermore, the system was tested on a variety of lignin model substrates containing β-O-4 linkage for the generation of fragmentation products in good to excellent results.Keywords:lignin;β-O-4;photocatalyst;Ni/TiO2;oxidant PCC
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 89
·48317-48321
·
IF 3.708
Yun Yu,Weimin Hou,Xuebing Hu,Yang Yu,Le Mi,Lixin Song
A novel superhydrophobic Al2O3 microfiltration membrane was prepared by the layer-by-layer assembly of TiO2 coating with subsequent fluorination grafting surface treatment by 1H,1H,2H,2H-perfluorodecyltriethoxysilane. The influence of surface morphology on membrane superhydrophobicity, pore size diameter distributions and pure water permeability of the different membranes were studied. By optimizing the grafting parameters, a needle-like surface of grafted TiO2-coated Al2O3 membrane with a water contact angle of 169.5° was obtained. The pure water permeability of different membranes varied from 100 l m−2 h−1 bar−1 before grafting to 3–5 l m−2 h−1 bar−1 after grafting, and the grafted superhydrophobic membrane showed excellent water repellence. The novel superhydrophobic membrane is shown to be promising for liquid–liquid and gas–liquid separation.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2016
·Vol. 28
·期 2
·1271-1280
·
IF 1.798
Wang Wenwen,Yang Dongjiang,Yang Weiyou,Sun Jin,Hou Huilin
The wide application of the titanium dioxide (TiO 2 ) as the photocatalysts is greatly hindered by its intrinsic large band gap and usually fast electron–hole recombination. Here, we reported the exploration of coupling g-C 3 N 4 nanoflakes to TiO 2 nanotubes with the anatase and TiO 2 (B) mixed phases (TiO 2 (AB)) toward the efficient visible-light-driven hybrid photocatalyst. It is found that coupling TiO 2 (AB) nanotubes with g-C 3 N 4 nanoflakes could bring a profoundly extension the visible light adsorption capacity and enhanced photogenerated carrier separation. Accordingly, they exhibit much higher efficient photocatalytic activities toward the degradation of sulforhodamine B under the visible light irradiation, which is enhanced for nearly 15 times to those of the TiO 2 (AB) and g-C 3 N 4 , suggesting their promising practical applications as novel and efficient semiconductor photocatalysts for the water purification.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2016
·
IF 9.307
Jingbo Mao,Jinxia Zhou,Zhi Xia,Zhiguang Wang,Zhanwei Xu,Wenjuan Xu,Peifang Yan,Kairui Liu,Xinwen Guo,Z. Conrad Zhang
Gold nanoparticles on a number of supporting materials, including anatase TiO2 (TiO2-A, in 40 nm and 45 μm), rutile TiO2 (TiO2-R), ZrO2, Al2O3, SiO2 , and activated carbon, were evaluated for hydrodeoxygenation of guaiacol in 6.5 MPa initial H2 pressure at 300 °C. The presence of gold nanoparticles on the supports did not show distinguishable performance compared to that of the supports alone in the conversion level and in the product distribution, except for that on a TiO2-A-40 nm. The lack of marked catalytic activity on supports other than TiO2-A-40 nm suggests that Au nanoparticles are not catalytically active on these supports. Most strikingly, the gold nanoparticles on the least-active TiO2-A-40 nm support stood out as the best catalyst exhibiting high activity with excellent stability and remarkable selectivity to phenolics from guaiacol hydrodeoxygenation. The conversion of guaiacol (∼43.1%) over gold on the TiO2-A-40 nm was about 33 times that (1.3%) over the TiO2-A-40 nm alone. The selectivity of phenolics was 87.1%. The products are mainly phenolic compounds with no aromatics and saturated hydrocarbons such as cyclohexane. The gold particle size ranging from 2.7 to 41 nm and water content were found to significantly affect the Au/TiO2-A-40 nm catalyst activity but not the product selectivity. The reaction rates of 0.26 and 0.91 (min–1 g-cat–1 cm3) were determined for guaiacol hydrogenation and catechol hydrogenation, respectively. Bimolecular methylation was established as the dominant mechanism for methyl group transfer among the phenolics. Two major pathways of guaiacol hydrogenation to phenolics over the 0.4Au-19 nm/TiO2-A-40 nm are proposed: (1) direct hydrogenation of guaiacol to form phenol and methanol, (2) hydrodehydroxylation of catechol intermediate from the transmethylation between guaiacol and phenol.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2017
·Vol. 28
·期 9
·6544-6551
·
IF 2.019
Wu Guanglei,Li Junli,Wang Kuikui,Wang Yiqun,Pan Chen,Feng Ailing
In this paper, titanium dioxide (TiO 2 )/phenolphthalein-type polyimide (PPPI) composite was synthesized in situ polymerization, the diamino phenolphthalein type compound and dimethylacetamide as the matrix, and TiO 2 as the filler. The mechanical property and thermal conductivity properties were used to characterize the properties of the obtained composite. A diamine monomer containing more benzene rings of phenolphthalein and an ether bond in its main chain were prepared, synthesized by a nucleophilic substitution reaction and a hydrazine hydrate reduction reaction. Polyimide composite had the same structure as that of a diamine monomer. And it was synthesized by solution imidization and heat imidization. The results showed that TiO 2 improved the dispersibility, alignment and interfacial strength of the TiO 2 /PPPI composite. The mechanical property of polyimide composite was increased with the increasing TiO 2 loading. And a suitable addition of TiO 2 could enhance the mechanical properties of polyimide system. Compared to polyimide resin, the TiO 2 /PPPI composite had a higher thermal conductivity with the increasing of TiO 2 content. All of these changes in properties were closely correlated with the TiO 2 /PPPI composite, which could form an interaction interface structure in the system.
研究领域:
材料科学
·
高分子化学
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 14
·8558-8567
·
IF 3.119
Jindong Wang,Wenzhi Li,Huizhen Wang,Ajibola Temitope Ogunbiyi,Xiaomeng Dou,Qiaozhi Ma
To improve the utilization of lignin, much effort has been devoted to lignin depolymerization with the aim to decrease waste and enhance profitability. Here, a dual property (acid and base) catalyst, namely S2O82−–K2O/TiO2, was carefully researched. Upon loading S2O82− and K2O onto TiO2, acid and base sites emerged, and S2O82− and K2O mutually enhanced the acid and base strengths of the catalyst enormously; this indeed facilitated lignin depolymerization. Under appropriate conditions, the yields of liquid product, petroleum ether soluble (PE-soluble) product and total monomer products were 83.76%, 50.4% and 28.96%, respectively. The constituents of the PE-soluble fraction, which are mainly monomers and dimers, can be used as liquid fuels or additives. In addition, after the catalyst was modified by Ni, better results were obtained. Surprisingly, it was found that the Ni enhanced not only the hydrogenation capacity but also the acidity. The highest high heating value (HHV) of the liquid product (33.6 MJ kg−1) was obtained, and the yield of PE-soluble product increased from 50.4 to 56.4%. The product can be utilized as a fuel additive or be converted to bio-fuel. This catalysis system has significant potential in the conversion of lignin to bio-fuel.
研究领域:
化学工程
·
可再生能源
·
催化科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS & DESIGN
·
2022
·
IF 9.417
Yingxuan Wang,Zhaoshuang Li,Jiping Wang,Jingran Wang,Xiangzhou Li,Chuntao Kuang
Blood repellent dressings plays an important role in trauma medicine. However, such dressings have poor hemostatic efficacy, and can cause infection, rendering them unsatisfactory for clinical application. We prepared a durable superhydrophobic coating for blood repellent dressing based on rosin acid and TiO 2 with a water contact angle of 155.7° and a sliding angle of 5°. The morphology and chemical composition of the coating were characterized by scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and X-ray spectroscopy (XPS), respectively. The superhydrophobic coating can withstand at least thirty sandpaper abrasions and sixteen washing treatments without losing its superhydrophobic properties. Meanwhile, the superhydrophobic coating demonstrated excellent antimicrobial activities against Gram-positive Staphylococcus aureus ( S. aureus ) (with log reduction = 1.73) and Gram-negative Escherichia coli ( E. coli ) (with log reduction = 1.74) and effectively prevented biofilm formation. Besides, the excellent biocompatibility of the superhydrophobic coating was verified by hemocompatible and cytotoxic assays. Finally, it was confirmed that the superhydrophobic coating can reduce blood loss and allows for high air permeability in in vitro tests. The superhydrophobic coating based on rosin acid and TiO 2 provides a simple way for preparing novel blood repellent dressings, which may have promising applications in wound dressings.
研究领域:
创伤医学
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2021
·Vol. 14
·期 18
·5354
·
IF 3.623
Jing Ma,Lihua Chu,Yanjiao Guo,Changxu Sun,Hao Yan,Ze Li,Meicheng Li
Photocatalytic water splitting for hydrogen production via heterojunction provides a convenient approach to solve the world crises of energy supply. Herein, graphene quantum dots modified TiO2hybrids (TiO2-GQDs) with a “caterpillar”-like structure exhibit stronger light absorption in the visible region and an enhanced hydrogen production capacity of about 3.5-fold compared to the pristine TiO2caterpillar. These results inferred that the addition of GQDs drastically promotes the interfacial electron transfer from GQDs to TiO2through C–O–Ti bonds via the bonding between oxygen vacancy sites in TiO2and in-plane oxygen functional groups in GQDs. Using a “caterpillar”-like structure are expected to provide a new platform for the development of highly efficient solar-driven water splitting systems based on nanocomposite photocatalyst.Keywords:GQDs;TiO2caterpillar;photocatalysts;hydrogen production;water-splitting
研究领域:
材料科学
·
能源科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Environmental Science and Technology
·
2023
·Vol. 20
·期 11
·11865-11876
·
IF 3.1
Xin X.,Liu H.,Sun J.,Gao K.,Jia R.
The composite material based on N- , S- , and Fe-doped TiO 2 (NSFe-TiO 2 ) synthesized by wet impregnation was used as a photocatalyst to rapidly degrade sulfadiazine. The photocatalytic degradation behavior and mechanism of sulfadiazine on NSFe-TiO 2 were investigated for revealing the role of degradation under ultraviolet light. The results showed that compared with TiO 2 , NSFe-TiO 2 markedly improved the efficiency in photocatalytic degradation of sulfadiazine: more than 90% of sulfadiazine could be removed within 120 min by NSFe-TiO 2 dosage of 20 mg L −1 . The process conformed to first-order reaction kinetics model. The parameters such as loaded amount of NSFe-TiO 2 , solution pH value, humic acid concentration and recycle numbers on removal efficiency were also studied. Compared to neutral and alkaline conditions, acidic condition was not conducive to the photocatalysis. HA, Ca 2+ , Cu 2+ and Zn 2+ in the actual water body had mild inhibition on sulfadiazine degradation in UV/NSFe-TiO 2 system. Fragments screened by high-resolution mass spectrometry were conducted to explore the oxidation mechanism and pathways of sulfadiazine degradation. On the whole, UV/NSFe-TiO 2 photocatalysis has a good effect on sulfadiazine removal.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）