MICROPOROUS AND MESOPOROUS MATERIALS
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2019
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IF 4.182
Hai-Tao Wang,Ya-Pan Liu,Hao Zhang,Na Chang,Wei Shao,Meng-Shan Shi,De Ao,Mei-Chan Lu
With the regular structures composed of metal clusters and organic ligands, metal-organic frameworks (MOFs) are expected to be the competent stabilizing matrix for nanoparticles and the excellent precursor of metal oxide with carbon species by means of high temperature pyrolysis , resulting to porous architectures with unexpected adsorptive or catalytic properties. Herein, we design and propose a facile route for preparing porous Carbon doped ZnO/TiO 2 @ZIF-8 (C–ZnO/TiO 2 @ZIF-8) multi-component nano-platform using TiO 2 coated ZIF-8 as precursor and template followed by thermal calcination . The resulted C–ZnO/TiO 2 @ZIF-8 nanocrystal simultaneously possesses original ZIF-8 morphology and porous structure with connected ZnO nanoparticles. As a result, C–ZnO/TiO 2 @ZIF-8 shows obviously better adsorption affinity towards methylene blue (MB). Moreover, benefit from the TiO 2 coating outside ZIF-8 matrix, escape of carbon species which originate from pyrolysis of organic ligands is efficiently inhibited, with the resulted materials doped with abundant carbon. Therefore, charge transfer and isolation of the resulted catalyst are promoted accordingly, with catalytic activity of the prepared C–ZnO/TiO 2 @ZIF-8 multi-component photocatalyst significantly increased by 1.8-fold and 3.0-fold compared to ZnO@ZIF-8 photocatalyst under irradiation of UV and visible light, respectively.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2025
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IF 21.1
Yi-Fan Qiao,Wen-Cui Li,Lei He,Jia Wang,Danhui Sun,Zihao Wang,An-Hui Lu
To efficiently convert ethanol into C 4+ olefins without an external hydrogen supply, this study designed an anatase-supported zinc oxide catalyst (ZnO/TiO 2 -A). Combining characterizations with kinetics measurements, we infer that the highly dispersed Zn-O-Ti sites efficiently promote ethanol dehydrogenation to acetaldehyde, which is identified as the rate-limiting step. Concurrently, Ti-O sites with strong C-C coupling ability convert acetaldehyde into high-carbon enal intermediates, which subsequently undergo hydrogenation and dehydration to yield C 4+ olefins with a high formation rate of 43.96 mmol C-atom ·g cat. −1 ·h −1 , outperforming most reported catalysts in the literature. Crucially, nuclear magnetic resonance spectroscopy analysis confirms that ethanol acts as an intrinsic hydrogen donor, supplying active hydrogen for the hydrogenation of C C and C O bonds in enal intermediates, thereby obviating the need for external hydrogen. This work presents a new strategy employing a non-precious metal oxide catalytic system for upgrading ethanol to high-value products.
研究领域:
催化化学
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能源化学
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材料化学
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有机转化
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2020
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IF 7.1
Yongshan Xu,Lingli Zheng,Chen Yang,Wei Zheng,Xianghong Liu,Jun Zhang
Constructing heterostructures with efficient modulation of electron transfer at the heterointerface affords great opportunity for electronic devices. Herein, a high performance nanosensor based on core-shell ZnO@TiO 2 nanorods is successfully realized for n-butanol detection. The n-n heterointerface formed between TiO 2 and ZnO allows for vast variation of conductivity due to electron confinement induced by their different works functions and enhances the response on exposure to gaseous molecules. Studies reveals that the shell thickness of TiO 2 has a great impact on the sensor performances, and the sensor based on ZnO@TiO 2 nanorods with 6.4 nm-thick TiO 2 shell delivers outstanding gas sensing properties in terms of high sensitivity, low detection limit (133 ppb), fast response-recovery, and excellent selectivity towards n-butanol detection. The mechanism for the improved gas sensing function is ascribed to the heterojunctions of core-shell nanostructure, the enhanced oxygen adsorption due to the TiO 2 shell and the fully electron-depleted TiO 2 shell layer with a thickness comparable to the Debye length. The strategy presented here is generally applicable and can provide some hints to design efficient electronic sensors with optimized performances.
研究领域:
材料科学
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化学传感器
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产品关联
DOI
高影响因子
International Journal of Electrochemical Science
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2023
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IF 1.5
Yuzhe Liu,Chunlian Quan
This research paper introduces a highly sensitive electrochemical sensor designed for the detection of the sports stimulant methyltestosterone, utilizing a unique ZnO/TiO 2 nanocomposite. Methyltestosterone, an extensively abused anabolic steroid in sports, calls for an efficient detection technique to maintain sporting integrity. The sensor was designed and synthesized with enhanced properties leveraging the specific characteristics of the ZnO/TiO 2 nanocomposite. The sensor demonstrated high sensitivity and selectivity towards methyltestosterone, outstripping traditional detection techniques. When subjected to real-world scenarios, including testing in synthetic urine samples, the sensor showcased outstanding precision and consistency, making it a robust tool for anti-doping control.
研究领域:
分析化学
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生物医学工程
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运动科学
✓ 已验证
产品关联
DOI
高影响因子
Crystals
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2020
·Vol. 10
·期 4
·325
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IF 2.404
Liqing Liu,Hui Wang,Dehao Wang,Yongtao Li,Xuemin He,Hongguang Zhang,Jianping Shen
The ZnO@TiO2core/shell nanowire arrays with different thicknesses of the TiO2shell were synthesized, through depositing TiO2on the ZnO nanowire arrays using the pulsed laser deposition process. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images show that these core/shell nanowires were homogeneously coated with TiO2nanoparticles with high crystallinity, appearing to be a rather rough surface compared to pure ZnO nanowires. The efficiency of ZnO@TiO2core/shell structure-based dye-sensitized solar cells (DSSCs) was improved compared with pure ZnO nanowires. This is mainly attributed to the enlarged internal surface area of the core/shell structures, which increases dye adsorption on the anode to improve the light harvest. In addition, the energy barrier which formed at the interface between ZnO and TiO2promoted the charge separation and suppressed the carrier recombination. Furthermore, the efficiency of DSSCs was further improved by increasing the thickness of the TiO2shell. This work shows an efficient method to achieve high power conversion efficiency in core/shell nanowire-based DSSCs.
研究领域:
材料科学
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能源技术
✓ 已验证
DOI
高影响因子
Journal of Nanomaterials
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2022
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IF 3.791
Qiqi Chang,Jun Xu,Yijun Han,Andrea Ehrmann,Tianhong He,Ruiping Zheng
As the electron transport layer of dye-sensitized solar cells (DSSCs), the photoanode is an important component that affects photoelectric conversion efficiency (PCE). The commonly used material titanium dioxide (TiO2) is difficult to prepare as nanostructures with large specific surface area, which affects dye loading and electrolyte diffusion. Herein, TiO2 nanofibers and ZnO-TiO2 composite nanofibers with different molar ratios are synthesized by electrospinning technology. The above nanofibers are coated on photoanodes by the doctor blade method to assemble DSSCs. The influence of the composite ratio of ZnO-TiO2 composite nanofibers on the photoelectric performance of the assembled DSSCs is explored. The ZnO-TiO2 composite nanofibers with a molar ratio of 1 : 2 have large specific surface area and porosity and have the smallest charge transfer resistance at the photoanode-electrolyte interface. The PCE of the nanofiber-modified DSSCs reaches a maximum of 3.66%, which is 56% higher than that of the TiO2 nanofiber-modified DSSCs. The photovoltaic parameters such as open circuit voltage (VOC), current density (JSC), and fill factor (FF) are 0.58 V, 10.36 mA/cm2, and 0.61, respectively. Proper compounding of zinc oxide (ZnO) can not only make the nanofibers absorb more dyes and enhance the light-harvesting ability but also improve the diffusion of the electrolyte and enhance the electron transport, thus successfully improving the power conversion efficiency of DSSCs.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2014
·Vol. 2
·期 20
·7313-7318
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IF 0
Ruosong Wang,Huaqiao Tan,Zhao Zhao,Guoqiang Zhang,Laiwen Song,Wenfei Dong,Zaicheng Sun
Nanostructured metal oxides such as ZnO and TiO2 have been extensively employed as self-cleaning coatings due to their large band gaps as well as their hydrophilic and photocatalytic properties. We have developed a simple hydrothermal method to coat thin TiO2 nanosheets with exposed (001) facets onto a ZnO nanorod array. The chemical stability of the ZnO nanorods was great improved due to the existence of the TiO2 layer. Owing to the porous structure of the ZnO@TiO2 nanorod arrays, this thin coating layer possesses anti-reflective properties. A transmittance improvement of ∼5% was observed for one-side coated FTO glass. This coating also exhibits good hydrophilic properties, after addition of the TiO2 nanosheets. More importantly, these ZnO@TiO2 nanorod arrays display excellent photocatalytic properties for the degradation of dye molecules, due to the heterojunction between the ZnO nanorods and TiO2 nanosheets. This heterojunction facilitates the charge separation of photo generated carriers. Based on the above features, the ZnO@TiO2 core/shell nanorod array film has many advantages as a self-cleaning coating.
研究领域:
材料科学
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纳米技术
✓ 已验证
产品关联
DOI
Journal of Ocean University of China
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2023
·Vol. 22
·期 2
·469-478
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IF 1.6
Mei Xueqiao,Li Chunhu
Photocatalyst Ag/ZnO-TiO 2 was prepared by template method. The catalyst was characterized by XRD, SEM, and UV-vis DRS. Rhodamine B (RhB) and target pollutants were used to evaluate the photocatalytic performance of the catalyst under 40 W UV-lamp. The photocatalytic degradation mechanism of Rhodamine B was discussed through free radical quenching experiment. The experimental results show that hexagonal ZnO-TiO 2 can be successfully prepared by template method, and nano Ag particles are evenly loaded on the catalyst. Under the reaction conditions of 1% catalyst input and 40 W UV-lamp, the catalytic degradation rate of RhB by Ag/ZnO-TiO 2 was 98.28%. The photocatalytic degradation mechanism of Ag/ZnO-TiO 2 was explored by free radical quenching experiment. The experimental results show that H + and ·OH play a major role in the photocatalytic degradation of RhB by Ag/ZnO-TiO 2 .
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials and Nanotechnology
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2016
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IF 1.109
JiaDong Chen,WeiSha Liao,Ying Jiang,DanNi Yu,MeiLing Zou,Han Zhu,Ming Zhang,MingLiang Du
In this study, novel titanium dioxide (TiO2) and zinc oxide (ZnO) hybrid photocatalysts in the form of nanofibres were fabricated by a facile method using electrospinning followed by a calcination process. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were employed to investigate the morphology and structure of the heterogeneous nanofibres. The photocatalytic performances were evaluated via the photodegradation of Rhodamine B (RhB) under irradiation with UV light. Due to the low recombination rate of photo-induced charge carriers, the high utilization efficiency of UV light and the large contact area with the target molecules, the ZnO/TiO2 hybrid nanofibres exhibited high catalytic activity towards the Rhodamine B, and the amount of Zn(OAc)2 in the precursor of these nanofibres played an important role in determining the photo decomposition performance.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
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2018
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IF 4.484
Wenting Sun,Sugang Meng,Sujuan Zhang,Xiuzhen Zheng,Xiangju Ye,Xianliang Fu,Shifu Chen
In the paper, the synthesis of ZnO/TiO2 nanocomposites with different main parts (TiO2 or ZnO) is studied. When TiO2 is the main part of the ZnO/TiO2 heterojunction photocatalysts (ZnO/TiO2), the photocatalytic activity is decreased rapidly with the increase of the amount of ZnO. The reason may be attributed to the relative p–n junction (p-ZnO/n-TiO2) produced between ZnO and TiO2. The migration directions of the electrons and holes in the relative p–n junction are opposite to the transfer directions of the photogenerated electrons and holes in the valence band (VB) and conduction band (CB). However, when ZnO is the primary part of the heterojunction photocatalysts (TiO2/ZnO), the photocatalytic activity of the samples increases with the increase of the TiO2 amount up to 5% (95% ZnO/TiO2). The reason may be that the migration directions of the electrons and holes in the relative p–n junction (p-TiO2/n-ZnO) are the same as the transfer directions of the photoexcited electrons and holes in VB and CB between the two semiconductors. It is proposed that the conductivity of the heterojunction photocatalyst will be changed with the difference of content for the two semiconductors, which in turn affects the migration directions of the electrons and holes in the heterojunctions and their photocatalytic activity.
研究领域:
材料科学
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光催化
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2019
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IF 3.45
Jun Song,Gang Sun,Jianyong Yu,Yang Si,Bin Ding
Rational design of semiconductor membrane photocatalyst with good mechanical flexibility and excellent photocatalytic activity is of significance for environmental remediation. Herein, flexible Ag@ZnO/TiO 2 fibrous membranes with hierarchical nanostructures were fabricated through combining a simple electrospinning method and subsequent hydrothermal reaction and photodeposition process. In the ternary nanocomposite, ZnO nanorods were firmly anchored onto TiO 2 nanofibers , while Ag nanoparticles were evenly decorated on the surface of both ZnO and TiO 2 . Benefiting from the improved light absorption, large surface area, and effective charge separation, the resultant Ag@ZnO/TiO 2 membranes displayed superior photocatalytic degradation efficiency of 91.6% toward tetracycline hydrochloride within 1 h, and also exhibited prominent antibacterial activity with a 6.5 log inactivation of E. coli after 1 h simulated solar light exposure. Significantly, the membrane photocatalyst still preserved structural integrity and mechanical flexibility after utilization. This study provides an alternative approach for designing and synthesizing flexible TiO 2 -based membrane photocatalysts toward high-efficiency water purification.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Zhangkai Qian,Jia-qi Bai,Mei Ma,Huangfei Liu,Mengdie Cai,Jingshuai Chen,Song Sun
N -methylation of amines, nitro compounds and nitriles with CO 2 and H 2 offers a promising strategy for CO 2 utilization. However, developing highly efficient and stable Cu-based catalysts for selective mono- N -methylation of aniline remains challenging. Herein, we report the successful synthesis of a Cu-ZnO/TiO 2 catalyst, with the optimized 5 %Cu-7.5 %ZnO/TiO 2 catalyst achieving a 96.7 % yield of N -methylaniline (MA) and an initial turnover frequency (TOF) of 7.4 h −1 after 6 h under 453 K, 2 MPa CO 2 and 4 MPa H 2 . This performance surpasses all reported Cu-based catalysts and rivals noble metal-based systems. The catalyst demonstrated reusability at least four cycles and versatility in the N -methylation of various amines, nitro compounds, and nitriles. Kinetic studies revealed reaction orders of 0 with respect to aniline concentration and CO 2 pressure, and 1 with respect to H 2 pressure. Based on kinetics and extensive characterization, we propose a reaction mechanism over 5 %Cu-7.5 %ZnO/TiO 2 , identifying Cu nanoparticles as the active sites. The process proceeds via N -phenylcarbamic acid and N -phenylformamide intermediates, with the hydrogenation of N -phenylcarbamic acid as the rate-determining step.
研究领域:
化学工程
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催化科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）