JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Guoli Chen,Kun Song,Xiaoming Huang,Wenbo Wang
Titanium dioxide (TiO 2 ) colloid was synthesized by using tetrabutyl titanate . TiO 2 (KH-570) intermediate was prepared by etherification reaction of TiO 2 colloid and KH-570. The CS-GMA intermediate was prepared by ring-opening reaction of chitosan (CS) and glycidyl methacrylate (GMA). Finally, copolymerization two intermediates obtain a new adsorbent, TiO 2 (KH-570)-g-(CS-GMA). The results manifest that the maximum adsorption amounts of toluene and Pb(II) are 56.62 mg/g and 623.56 mg/g, respectively. The adsorption of TiO 2 (KH-570)-g-(CS-GMA) adsorbent for toluene and Pb(II) accord with the pseudo-second-order kinetics mechanism and Langmuir equation, indicate that the TiO 2 (KH-570)-g-(CS-GMA) adsorbent has better adsorption effect on toluene and Pb(II).
研究领域:
环境科学
·
材料科学
·
化学工程
·
污染控制
·
吸附技术
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Zhiwei Wang,Hongfeng Yin,Yun Tang,Qin Hou,Chen He,Hudie Yuan
Herein, we constructed an ordered nanoporous embedding nanoparticles composite by anodic oxidation of Ti 3 SiC 2 in fluorine containing organic electrolyte. Compared to anodized Ti which resulted in TiO 2 nanotubes , the anodized Ti 3 SiC 2 (ATSC) led to the formation of nanostructured TiO 2 /C/SiO 2 composite. The morphologies of oxides in the composite also varied with different anodization parameters. The ATSC could be directly used as an electrode without further processes, which possessed a superior structure and composition with a visible-light photocurrent density of 7.56 μA cm −2 , initial reversible area capacity of 6.18 F cm −2 , which were respectively 1.32 and 6.87 times higher than those of the anodized Ti (AT), respectively. The ATSC synthesized by such a feasible fabricating strategy shows favorable photoelectrochemical properties and remarkable stability, and may broaden the bifunctional material prospects of anodized MAX phases.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
·
2015
·
IF 2.489
Jingzhong Zhao,Weiqiang Xing,Yang Li,Kathy Lu
Oxygen-deficient anatase TiO 2 sheets with dominant (001) facets are becoming a hot research topic due to their promising high activity in heterogeneous reactions . In this work, a series of (001) facets dominated TiO 2 with distributed oxygen vacancies and Ti 3+ was prepared by a simple hydrothermal method with the TiB 2 as a precursor. The as-prepared powders were characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Transmission Electron Microscope (TEM), X-ray photoelectron spectroscopy (XPS) and UV–visible diffuse reflectance spectroscopy (UV–vis). The results show that the particle size of as-prepared TiO 2 increases and its band gap narrows with the hydrothermal temperature increasing from 140 °C to 180 °C. Besides, oxygen vacancies and Ti 3+ are generated during the TiB 2 hydrolysis, which leads to new absorption spectrum in the visible light region. Photocatalytic test shows that sample prepared at 180 °C presents the highest degradation efficiency.
研究领域:
材料科学
·
光催化
·
纳米材料
·
表面化学
·
半导体材料
✓ 已验证
DOI
高影响因子
JOURNAL OF SOILS AND SEDIMENTS
·
2016
·Vol. 17
·期 2
·536-542
·
IF 2.206
Zhang Jinyang,Li Chuxian,Wang Dingyong,Zhang Cheng,Liang Li,Zhou Xiong
Purpose The environmental safety of both nano-TiO 2 particles and mercury (Hg) pollution has been of widespread concern. Soils and sediments were the main receiving environments of nano-TiO 2 and Hg. There was a strong association between nano-TiO 2 with Hg compounds. Very limited research has been carried out on the impact of nano-TiO 2 on the environmental behavior of Hg in sediments. The objective of this study was to investigate the effects of nano-TiO 2 on the release and transformation of Hg in sediments. Materials and methods Two types of TiO 2 nanoparticles were employed. Sediment samples were collected in the water level fluctuating zone of the Three Gorges Reservoir, China. Sediment samples spiked with HgCl 2 solution were taken as Hg-contaminated sediments. The flooding experiments were conducted using capped borosilicate glass bottles containing 300 ml TiO 2 suspensions (0.2 g L −1 and 0.4 g L −1 ) and 30 g original or Hg-contaminated sediment samples outdoors. All experiments were conducted in triplicate. Water samples were collected at determined interval times over a 60-day period. Sediments were collected on the 60th day. Total Hg (THg) and methylmercury (MHg) in both water and sediment samples and Hg speciation just in sediment samples were determined. A series of control samples without TiO 2 addition were also prepared. Results and discussion The results showed that nano-TiO 2 particles at high content (4 g kg −1 ) promoted the release of Hg in sediments, and the anatase particles showed a stronger effect. Methyl Hg concentrations in waters of nano-TiO 2 treatments significantly decreased by the 10th day. The effect of nano-TiO 2 greatly depended on anatase and rutile particles. After that, methyl Hg concentrations had no significant difference between nano-TiO 2 treatments and the control, except 2 g kg −1 rutile treatment by the 20th day. The changes of Hg speciation in sediments demonstrated that nano-TiO 2 inhibited the transformation of Hg-bound organic matter into the oxidated state, especially upon 2 g kg −1 rutile treatment. This was consistent with the lower MHg concentrations in the 2 g kg −1 rutile treatment. Conclusions Both anatase and rutile nano-TiO 2 were found to affect the release of Hg in sediment. Nano-TiO 2 promoted THg release in sediments and posed an increased risk of Hg contamination in waters, especially for anatase particles. Moreover, nano-TiO 2 inhibited the methylation process of Hg in sediments at the initial stage of flooding and could affect the transformation of Hg speciation in sediments, especially for low-content rutile particles.
研究领域:
环境科学
·
地球化学
·
水体生态学
·
污染控制
·
环境毒理学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 21
·52199
·
IF 3.057
Wenjiao Wang,Mingming Zheng,Jiajia Ren,Mingliang Ma,Xunqian Yin,Tingxi Li,Yong Ma
Magnetic Fe 3 O 4 /MnO 2 /TiO 2 /polypyrrole (PPy) heterostructure as adsorbent for adsorbing Mn 7+ was synthesized by combining hydrothermal method and chemical oxidation method. The heterostructure was characterized by field-emission scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometer. Its saturation magnetization is 18.88 emu/g, so it is easy to separate it from the solution. The feasibility of Fe 3 O 4 /MnO 2 /TiO 2 /PPy heterostructure to remove Mn 7+ was researched in detail. It is found that the optimal pH is 2. The initial adsorption rate can reach 4.60 mg/g min. At 288.15 K, the maximum equilibrium adsorption capacity is 202.8 mg/g. Adsorption kinetics follows a pseudo second order model, as well as is determined by through membrane diffusion processes. The Langmuir isotherm model is used to describe the adsorption isotherm behavior. Besides, thermodynamic parameters indicate spontaneous adsorption behavior, and entropy of the endothermic reaction increases. Finally, the cycle test results show that the adsorbent has better cycle performance, displaying broad application prospects.
研究领域:
环境科学
·
材料科学
·
化学工程
·
纳米技术
·
污染控制
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2023
·
IF 3
Ensi Cao,Yixuan Zhang,Yongjia Zhang,Wentao Hao,Bing Sun,Li Sun
To enhance the acetone sensing capabilities of LaFeO 3 nanoparticles for practical applications in breath analysis, commercial n-type rutile TiO 2 nanoparticles were utilized as additives and directly mixed with LaFeO 3 nanoparticles synthesized via a sol–gel method. The obtained TiO 2 -LaFeO 3 nanocomposites were characterized by XRD, SEM, BET, and XPS. Compared to pure LaFeO 3 nanoparticles, the resulting TiO 2 -LaFeO 3 nanocomposites exhibited higher surface reactivity, as evidenced by their larger specific surface areas and higher oxygen vacancy contents. The introduction of TiO 2 also facilitated the formation of p-n heterojunctions, which enhanced the regulation of acetone molecules on internal carrier conduction within the nanocomposites. Therefore, the TiO 2 -LaFeO 3 nanocomposites demonstrated improved acetone sensing performance, including higher vapor response values, selectivity, and faster response/recovery speeds. Among the series of nanocomposites, those with an addition of 10 wt% TiO 2 exhibited the highest vapor response value (37.3 to 100 ppm) and the greatest selectivity against methanol and ethylene glycol at the prime operating temperature of 144 °C.
研究领域:
材料科学
·
纳米技术
·
传感器
·
表面化学
·
呼吸分析
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
·
2016
·
IF 3.958
Lei Zhao,Baoyue Zhang,Xin Xiao,Feng Long Gu,Rui-Qin Zhang
Active species such as holes, electrons, hydroxyl radicals ( OH), and superoxide radical anions ( O 2 − ) involved in the photocatalytic oxidation of benzyl alcohol (BA) into benzaldehyde (BAD) on TiO 2 under ultraviolet (UV) light were investigated by adding corresponding scavengers. The experimental results show that the oxidation of BA into BAD is driven mainly by the holes and OH radical. The role of dissolved O 2 was studied by bubbling N 2 through the reaction. The results show that the dissolved O 2 is, to some extent, the source of OH. Additional density functional theory (DFT) calculations identified two H-abstraction pathways ( R abs OH and R abs α). The structure of the R abs OH product is less stable and tends to transfer resulting in the R abs α product. The holes are the main driving force for the abstracting of H from BA. The OH radical combines with the H-abstract product to form a precursor of product BAD, detected by LC–MS technique ( m / z 123), which then undergoes an intramolecular dehydration reaction to form BAD. The results will help to select the optimal active species for the photocatalytic oxidation of BA into BAD on TiO 2 under UV light.
研究领域:
物理化学
·
光催化
·
环境化学
·
材料化学
·
理论计算化学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Zhongming Wang,Kun Wang,Xiaoying Peng,Qiang Geng,Xun Chen,Wenxin Dai,Xianzhi Fu,Xuxu Wang
The photoconductivity and the gas sensing property of TiO 2 at room temperature under ultraviolet (UV) irradiation were compared with those under visible light irradiation (≥420 nm), respectively. It was found that UV light could cause the photoconductivity of TiO 2 and its sensing response to both ethylene and oxygen, while the visible light at 420 nm could cause the photoconductivity of TiO 2 and its sensing response to oxygen but not to ethylene. This indicates that the photo-assisted gas sensing performance of TiO 2 was dependent on its light-excited behavior: The intrinsic excitation of TiO 2 induced by UV light could produce both the holes and electrons, which exhibited a respective response to ethylene and oxygen, while the extrinsic excitation of TiO 2 induced by visible light maybe only produced the free electrons but not free holes, resulting in only a response to oxygen. Furthermore, it was found that the visible-light enhanced conductivity maybe depend on the Ti–bonded hydroxyls (Ti–OH) at TiO 2 surface. With the removal of Ti–OH by increasing temperature, the visible light could not produce the photoconductivity of TiO 2 . It was proposed that Ti–OH groups act as the shallow trapped level to cause the extrinsic excitation of TiO 2 .
研究领域:
材料科学
·
半导体物理
·
传感器技术
·
光化学
·
表面科学
·
纳米材料
✓ 已验证
DOI
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2021
·
IF 7.328
Yunfeng Wu,Yu Zang,Liang Xu,Jianjun Wang,Hongge Jia,Fengjuan Miao
High-performance conjugated microporous polymer (CMP)/TiO 2 photocatalytic antibacterial nanocomposites were successfully synthesized by in situ Sonogashira polymerization. TiO 2 was uniformly dispersed onto the surface and within the CMP which show the microporous nature with narrow pore size distribution. The high crystallinity and thermal stability of the CMP/TiO 2 nanocomposites are attractive for use as antibacterial materials. The composites we prepared showed excellent photocatalytic antibacterial properties for the inactivation of Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) under visible light irradiation. The photocatalytic antibacterial rates of nanocomposites against E. coli and S. aureus after 120 min of visible light irradiation were 98.14% and 100%, respectively. The superoxide anion ( O 2 − ) was confirmed to be an important substance in the antibacterial process above. The cytocompatibility of the antibacterial agents was studied in terms of cytotoxicity against NIH 3T3 fibroblasts. More than 95% of the cells were still alive in the presence of the nanocomposites, both without and with light irradiation, indicating the good cytocompatibility of the nanocomposites. Judging from the excellent photocatalytic antibacterial properties and ultralow toxicity of nanocomposites, these materials can be used in many fields such as medical treatment, transportation and construction.
研究领域:
材料科学
·
纳米医学
·
生物材料
·
光催化
·
抗菌治疗
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 27
·10593-10600
·
IF 8.262
Wei Wen,Jin-Ming Wu,Yin-Zhu Jiang,Jun-Qiang Bai,Lu-Lu Lai
Li-ion microbatteries find wide applications in microdevices. It is important to develop electrode materials with high areal capacity, excellent rate capability and superior safety for microbatteries. TiO2 nanowire arrays satisfy the requirements of high areal capacity, short transport lengths and superior safety for microbatteries, but their areal/volumetric capacity is hindered by the insufficient surface area. TiO2 nanotrees can effectively eliminate these disadvantages of TiO2 nanowires; however, the electrochemical performances of TiO2 nanotrees for Li-ion microbatteries remain unexplored. It is highly desired yet challenging to construct two-dimensional TiO2 nanobranches with an ultrathin thickness and large length on nanoarrays, to maximize the surface area and structural hierarchy of electrodes. Herein, we developed a novel synthetic strategy to fabricate TiO2 nanotrees by depositing anatase/TiO2(B) mixed phase ultrathin nanobelts onto single-crystalline anatase nanowire arrays. The nanobelt branches were several nanometers in thickness and 200–260 nm in length. The growth process and the electrochemical mechanism were investigated. The unique nanoarchitecture and optimal phase structure endow the electrode with high areal capacity and rate capability, which is the best performance for TiO2 nanowire arrays ever documented. The 2nd discharge capacity of the TiO2 nanotrees at 0.1 mA cm−2 is ca. 267 μA h cm−2, corresponding to a volumetric capacity of 330 mA h cm−3. The TiO2 nanotrees have an areal capacity of 205, 141, 97 and 69 μA h cm−2 at a current density of 0.5, 2.0, 5.0 and 10.0 mA cm−2, respectively. The capacity can remain stable for 400 charge–discharge cycles at 1.0 mA cm−2. The present strategy may give hints to elegant electrode designs for energy applications.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
微电子器件
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 11
·8403-8412
·
IF 2.22
Wang Ting,Ma Qing,Gao Shang,Huang Mengshi
Highly regular TiO 2 nanotube arrays (TNTs) with interstitial nitrogen as the dominant point defect have been successfully prepared by annealing the as-anodized TNTs in N 2 in a temperature range of 400–650 °C. Using analysis methods that include field emission scanning electron microscopy, X-ray diffraction patterns, and Raman spectroscopy, the thermal stability of TNTs annealed in N 2 was found to be higher than that of TNTs annealed in O 2 . The interstitial nitrogen is considered as the dominant point defect in TNTs annealed in N 2 , which results in the notably improved thermal stability of the highly ordered TNTs. However, the content of hydroxyl oxygen on the surface of TNTs is significantly influenced by annealing temperature, which is closely related to photocatalytic activity. Optimized photocatalytic property of photodegradation of MO with a pseudo-first-order reaction constant k value of (5.065 ± 0.139) × 10 –2 h −1 is achieved for TNTs annealed in N 2 at 600 °C. These findings serve to provide simple and versatile guidelines to fabricate highly ordered TNTs with controllable point defects, enhanced thermal stability, and a high level of photocatalytic activity.
研究领域:
材料科学
·
纳米科技
·
光催化
·
表面化学
·
功能材料
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2018
·
IF 3.23
Hongjing Wu,Shaohua Qu,Kejun Lin,Yuchang Qing,Liuding Wang,Yuancheng Fan,Quanhong Fu,Fuli Zhang
It has been rarely reported that the microwave absorption materials can exhibit excellent low-frequency EM wave absorbing properties. In this paper, we synthesized steady short carbon fibers (SCFs)@TiO 2 composites by using simple one-pot hydrothermal process. The conductive short carbon fibers could be separated by TiO 2 nanoparticles from each other and reduced the conductivity of composite materials as a whole, meeting the requirements of impedance matching . With the introduction of SCFs content, SCFs@TiO 2 composites showed improved tan δ E values at low frequencies, implying the enhanced microwave attenuation ability at low and medium frequency. We unexpectedly found that the SCFs@TiO 2 composites exhibited very strong absorbing peaks ( i.e. , −46.3 dB) at low frequencies with relatively thin matching thickness. Interestingly, when the thickness of the SCFs@TiO 2 composite was only 1.0 mm, the absorbing bandwidth with a RL value less than −10 dB was over 14.3–16.7 GHz ( i.e. , absorbing frequency bandwidth is 2.4 GHz).
研究领域:
材料科学
·
电磁功能材料
·
纳米复合材料
·
微波吸收材料
✓ 已验证
DOI
高影响因子