CRYSTENGCOMM
·
2015
·Vol. 17
·期 26
·4895-4902
·
IF 4.034
Changchao Jia,Hsueh-Shih Chen,Ping Yang
In this paper, TiO2 beads were deposited on Ag nanowires to create necklace-like Ag nanowire@TiO2 (Ag NW@TiO2) heterostructures for the first time. They were fabricated via a two-step synthetic method, including the preparation of uniform Ag NWs and the deposition of TiO2 on the Ag surface. Thioglycolic acid (TGA) molecules were used as binding agents to solve the tricky issue of substantial lattice mismatch between the Ag NW core and the TiO2 shell. The amount of water and the permittivity of the solvents are found to be important factors for the formation of the necklace-like heterostructures. Moreover, by varying the amount of titanium butoxide (TBT), the diameter of the TiO2 beads can be feasibly changed. The photocatalytic performance of necklace-like Ag NW@TiO2 was evaluated via degradation of methyl orange (MO) under ultraviolet (UV) light. The results reveal that the molar ratio of TiO2 to Ag contributes to the synergistic effect on the photocatalytic activity, and the best Ti/Ag ratio is found to be 2.8 for the highest photocatalytic performance of the Ag NW@TiO2 heterostructures.
研究领域:
材料科学
·
纳米技术
·
光催化
·
表面工程
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2024
·
IF 5.4
Jiajing Zhu,Hui Wang,Yuqi Zhai,Liangjun Huang,Jie Cui,Liuzhang Ouyang,Min Zhu,Jacques Huot
MgH2 is a promising solid-state hydrogen storage medium with a high hydrogen capacity and low cost, but it suffers from high hydrogen sorption temperatures. In this work, Cr-doped TiO2 solid solution nanocatalysts were synthesized and demonstrated to significantly reduce the hydrogen sorption temperatures and pressure of MgH2. The Ti(5Cr)O2 catalyzed MgH2 releases over 6.1 wt % of H2 at 200 °C, and even at 175 °C, 2.62 wt % H2 can be desorbed. The dehydrogenation activation energy is greatly reduced to 85.3 ± 8.7 kJ/mol, which is ∼49.7 kJ/mol less than that observed for pure MgH2. The dehydrogenated product can absorb 4.5 wt % of H2 within 10 s at a low temperature of −20 °C and back pressure of 30 bar, or the hydrogen uptake content can reach 4.81 wt % under 5 bar and 75 °C. The mechanism study indicates that the Cr-doped TiO2 can markedly reduce the adsorption energy and dissociation energy barrier of H2 molecules and greatly enhance the dissociation ability of H on the catalyst surface. This work demonstrates the potential of modified TiO2 as a cost-effective and efficient catalyst for Mg-based hydrogen storage materials.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL PHYSICS
·
2024
·
IF 2
Xuecheng Ren,Mingxing Xiao,Kaidong Zhan,Fan Wu,Quinn Qiao
Inorganic lead-free perovskite Cs 3 B i2 I 9 has attracted extensive attention due to its enhanced stability and environmental friendliness. However, the photon-to-current conversion of Cs 3 B i2 I 9 perovskites is not efficient, partly due to inefficient electron-hole separation. In this manuscript, BiFeO 3 was deposited at the interface of Cs 3 Bi 2 I 9 /TiO 2 as the interface modifier by sol–gel method, and the photocurrent and responsiveness of the Cs 3 B i2 I 9 /BiFeO 3 /TiO 2 were significantly higher than those of the Cs 3 B i2 I 9 /TiO 2 based device. Kelvin probe force microscope, photoelectrochemical impedance spectroscopy and in-situ surface photovoltage spectra demonstrated that a self-polarized electric field of BiFeO 3 contributed to the separation of photogenerated charge carriers at the Cs 3 B i2 I 9 /TiO 2 interface. By analyzing the surface photovoltage phase spectra via a vector model method, complicated surface photovoltage processes were identified, and a detailed relationship between photocurrent generation and transfer characteristic of the photogenerated charge carriers have been discussed.
研究领域:
材料科学
·
光电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2013
·
IF 2.39
Zhongshan Ren,Xiaojun Hu,Xiangxin Xue,Kuochih Chou
The solid state reactions in Fe 3 O 4 –TiO 2 system has been studied by diffusion couple experiments at 1323–1473 K, in which the oxygen partial pressure was controlled by the CO–CO 2 gas mixture. The XRD analysis was used to confirm the phases of the inter-compound, and the concentration profiles were determined by electron probe microanalysis (EPMA). Based on the concentration profile of Ti, the inter-diffusion coefficients in Fe 3 O 4 phase, which were both temperature and concentration of Ti ions dependent, were calculated by the modified Boltzmann–Matano method. According to the relation between the thickness of diffusion layer and temperature, the diffusion coefficient of the Fe 3 O 4 –TiO 2 system was obtained. According to the Arrhenius equation, the estimated diffusion activation energy was about 282.1 ± 18.8 kJ mol −1 .
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2013
·Vol. 92
·期 5
·851-860
·
IF 1.003
Zhenhua Pan,Qizhou Cai,Qiang Luo,Xinwei Li
The mechanism and kinetics of synergetic effect in TiO 2 /O 3 /UV process on H-acid degradation were investigated. The experimental results showed that H-acid removal rate of TiO 2 /O 3 /UV process was the highest among TiO 2 /UV, O 3 /UV and TiO 2 /O 3 /UV processes. The investigation of reactions with suitable active species scavengers confirmed that H-acid was mainly oxidised by ozone and holes on TiO 2 in the TiO 2 /O 3 /UV process. The recombination between holes and electrons in TiO 2 reduced in the presence of ozone, as indicated by fluorescence emission spectra. Moreover, the intermediates generated during H-acid oxidation in various processes were analysed by LC/MSD trap. It is proposed that H-acid was oxidised to polyhydroxy aromatics, benzene carboxylic acids and quinoids in the first step. Then, saturated aliphatics carboxylic acids were formed and mineralised to inorganic compounds through the Photo-Kolbe reaction. Finally, a kinetic study on TiO 2 /UV, O 3 /UV and TiO 2 /O 3 /UV processes was conducted and it was confirmed that both ozonation and photocatalytic activity were improved in TiO 2 /O 3 /UV process because of the synergetic effect.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
FERROELECTRICS
·
2018
·
IF 0.728
Yuguo Zhuo,Jun Liu,Qingshan Li
Nano-TiO2/MDI-50 based waterborne polyurethane composites were prepared with MDI-50, polypropylene glycol (PPG) and nano-TiO2 as main materials. Nano-TiO2 was modified using r-aminopropyltriethoxysilane (KH550) as modifier in order to improve the dispersion of nano-TiO2 in WPU. The composites morphologies and physical states were investigated using scanning electron microscopy (SEM), thermogravimetry analysis (TG), fourier transform infrared (FTIR) spectroscopy and UV-visible (UV-Vis) spectroscopy. Scanning electron microscopy observations revealed that modified nano-TiO2 has good dispersibility. Results from FTIR and TG suggested that the modified nano-TiO2 had been successfully introduced to the polyurethane molecular chain and the thermal decomposition temperature of nano-TiO2/MDI-50 based waterborne polyurethane composites doubled under the same thermal weight loss. Results from UV-Vis suggested that when 2% of modified nano-TiO2 was added, maximum absorbance of composites were significantly improved and was twice higher than that of pure waterborne polyurethane.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Jiahao Wu,Jielei Tu,Hua Yang,Hao Wu,Zhangyang Xv,Weichen Wang
The efficiency of photovoltaic (PV) modules, the core unit for converting solar energy to electricity, is limited by the reflection loss of the glass cover and the adsorption of organic pollutants. Thus, the development of coatings with antireflective and self-cleaning composite functions is important. In this study, based on the sol-gel method, hollow MgF 2 /TiO 2 (MgF 2 @TiO 2 ) composites were prepared and, combined with the Essential Macleod software, coatings were designed and optimized. Using this approach, a three-layer antireflective coating with a self-cleaning function was developed. Moreover, subjecting the MgF 2 @TiO 2 composites to 24 h heat treatment resulted in the production of MgF 2 with a stable hollow rod structure and a refractive index of 1.18. The photocatalytic performance of TiO 2 was enhanced by optimizing the annealing temperature, and the strongest effect was achieved at 300 °C. In addition, the optimization of the coating structure resulted in a gradient refractive index coating with high process tolerance, with an average reflectance of 0.81% in the visible wavelength band. The application of the coating to mini-PV modules increased the light transmittance to 97.58% and the efficiency of the module by 5.71%, with a strong self-cleaning effect. The coating was demonstrated to have excellent durability and reliability upon exposing it to 2000 h of damp heat and subjecting it 1000 abrasion cycles. This study promotes the design and application of functional coatings on the surfaces of PV modules.
研究领域:
材料科学
·
能源技术
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Ning Lu,Junzhuo Cai,Baoling Niu,Ye Zhou,Guohua Zhao
Endowing traditional photocatalysis with selectivity for a class of characteristic pollutants is important in environmental science. Using PAEs-TiO 2 as a selective photocatalyst, 302.5 μg L −1 of 11 phthalic esters (PAEs) were preferentially removed to 4.94 μg L −1 in the presence of 10 mg L −1 of natural organic matter via specific hydrogen bonds or cation-π interactions. Further, degradation of PAEs is a lower risk pathway for PAEs-TiO 2 . The in-situ photocatalytic electron paramagnetic resonance initially revealed that PAEs-TiO 2 facilitated the ring opening and mineralization of PAEs, resulting in nearly 100 % detoxification. In actual wastewater, PAEs were not detected after treatment with PAEs-TiO 2 . Further, the energy cost was reduced by 48.1 %, reaching discharge standard. This study offers new sights into selective photocatalysis of a class of pollutants with similar molecular structure.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Huilan Zhuang,Lun Wang,Sijie Shao,Haitong Jing,Panpan Xue,Tingjie Bai,Jinpeng Deng,Xuemei Zeng,Xian Qin,Shuangqian Yan
Ferroptosis has emerged as a novel approach to suppress tumor growth through the iron-dependent accumulation of lipid peroxides, providing new opportunities for cancer therapy. However, the effectiveness of ferroptosis is impeded by the substantial neutralization of reactive oxygen species (ROS), generated through the Fenton reaction, by the high level of glutathione in cancer cells. Here we report a titanium metal–organic frameworks (MOFs)-derived method to create black TiO 2 nanoparticles with excellent photocatalytic performance. The nanoparticle has a narrow bandgap of 1.02 eV, multiple discrete gap states, and a high density of oxygen vacancies (46.2 %), facilitating ROS generation under 1064-nm light irradiation. When coated with a tannic acid/Fe 3+ layer, the resulting nanocomposite possesses the ability to deplete glutathione concentration, preventing the newly generated ROS from being neutralized and promoting ferroptotic cancer cell death. Complemented by photothermal and chemodynamic effects, in vivo experiments demonstrate a high tumor inhibition rate of 89.8 %. The utilization of MOF-derived nanomaterials represents a universal strategy, offering a solution for ferroptosis-based therapy in solid tumors and contributing to the development of smart, optically active materials with diverse applications in biological contexts.
研究领域:
生物医学
·
材料科学
·
肿瘤学
✓ 已验证
产品关联
DOI
高影响因子
PROPELLANTS EXPLOSIVES PYROTECHNICS
·
2019
·Vol. 44
·期 4
·438-446
·
IF 1.634
Qing Zhu,Chun Xiao,Xiao Xie,Bao-hui Zheng,Shang-bin Li,Guan Luo
The appropriate structure and properties of a composite material, including the morphology, particle size, and bond strength, are very important for its performance and practical applications. The energetic material HMX (C 4 H 8 N 8 O 8 , cyclotetramethylenetetranitramine) is typically mixed with nanocatalysts to improve its thermal decomposition, which is advantageous for its detonation performance in practical applications. Inspired by the bioadhesion of mussels, a HMX@PDA@TiO 2 (HMX first coated with PDA film and second coated with TiO 2 nanoparticles) composite was developed in this study to greatly advance the thermal decomposition temperatures. A simple stirring process was used to prepare the composite from HMX and TiO 2 nanoparticles under dopamine solutions with different pH values. Nanocatalyst TiO 2 nanoparticles were anchored on the surface of HMX by reacting with the dopamine and polydopamine coatings. Compared with other reference samples, the thermal behavior of the obtained composite showed that the starting decomposition temperature was lower, at approximately 60 °C, and that the decomposition peak decreased by 35 °C, indicating that the composite properties should have great effects on the thermal performance of the materials. The findings offer a valuable composite preparation method to enhance the thermal behavior and the effect of the catalyst on the composite via bonding effects.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2016
·Vol. 100
·期 1
·333-342
·
IF 2.787
Linhui Yu,Yangming Lin,Jing Huang,Sen Lin,Danzhen Li
Carbon-doped TiO 2 nanomaterials have been successfully synthesized via an effective two-step procedure involving hydrothermal method and followed by a low-temperature calcination treatment process, through which a controllable amount of carbonate-like species could be incorporated into TiO 2 . First-principles calculations suggest the TiO 2 doped with carbon in form of carbonate-like species can effectively extend the adsorption of the material from ultraviolet region to visible light. And it is experimentally found that carbon-doped TiO 2 nanomaterials exhibit much higher photocatalytic activity than reference P25 and TiO 2− x N x catalysts toward the liquid-phase degradation of organic pollutants under visible light (420 nm < λ < 800 nm) irradiation. The presence of synergic effect between carbonate-like doping and anatase TiO 2 is believed to play an essential role in affecting the photocatalytic reactivity, and the response to the visible light is ascribed to the narrowed band gap energy controlled by carbon doping. Moreover, the roles of active species in the photocatalytic process are compared using different types of active species scavengers. Meanwhile, the degradation mechanism of the photocatalysis is proposed. It is hoped that our work could provide valuable information on the design of carbonate-like doped semiconductor with more excellent properties and set the foundation for the further industrial application.
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
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Chong Xie,Shenghui Yang,Jianwen Shi,Beibei Li,Chen Gao,Chunming Niu
The stability of MnO x based low temperature SCR catalysts remained to be a serious issue. This report explored use of multi-walled carbon nanotubes (MWCNTs) network with uniform structure as a “rigid” pore template for synthesis of mesoporous MnO x -TiO 2 SCR catalyst with high surface area and high stability. The results showed that MWCNT network imposed MnO x -TiO 2 catalyst a mesoporous porosity with a narrow pore size distribution centered on ∼13.2 nm and a surface area of 131.6 m 2 g −1 stabilized at 500 °C. The mesoporous structure was formed by interconnected nanoparticles, comprised of crystallized rutile TiO 2 core surrounded by amorphous MnOx , with an average diameter of ∼8 nm. The catalyst exhibited an excellent low temperature SCR activity and selectivity as well as high resistance to deactivation and poison by H 2 O and SO 2 . SnO 2 modification led to degradation of catalytic performance in low temperature (60–180 °C) side, but improvement at high temperature side (240–360 °C), especially at high gas velocity, which can be attributed to change in structure, reactivity of MnO x and surface acidity induced by SnO 2 addition.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）