ANALYTICAL CHEMISTRY
·
2018
·
IF 6.042
Hongyan He,Xiuhong Peng,Ying Yu,Zeming Shi,Mo Xu,Shijun Ni,Ying Gao
Photochemical vapor generation (PVG) is emerging as a promising analytical tool for Te determination, thanks to its efficient matrix separation, and simple and green procedure. However, the low PVG generation efficiency of Te is the bottleneck for its wide application in environmental samples containing trace Te. Herein, we reported a high efficient PVG for Te determination by synergistic effect of ferric ion and nano-TiO2. The analytical sensitivity was enhanced approximately 15-fold for Te(IV) in the presence of both ferric ions and nano-TiO2, comparing to conventional PVG. Besides, the use of nano-TiO2 can provide Te(VI) and Te(IV) an equal and high PVG efficiency in the presence of ferric ions, owned to the high photocatalytic performance of TiO2 under short-wavelength UV irradiation (254 and 185 nm). Under the optimized experimental conditions, a detection limit of 1.0 ng L–1 was obtained. The precision of replicate measurements was 2.3% (RSD, n = 7) at 0.5 μg L–1 for Te(IV). The methodology was validated by successful determination of Te in surface waters and two standard reference sediment samples. To our best knowledge, this is the first report of the synergistic enhancement of transitional metal ions and nano-TiO2 in PVG, which possesses potential for highly sensitive determination of vapor-forming elements.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
·
2017
·
IF 4.636
Yanping Fan,Zhenluo Yuan,Guodong Zou,Qingrui Zhang,Baozhong Liu,Qiuming Peng
Differing from graphene with a carbon element component, analogous metallic-graphene two-dimensional layered titanium carbide (2D MXene) provides more opportunities to achieve better surface functionalization. Herein, a thin layered 2D MXene/A-TiO 2 composite was prepared by chemical exfoliation and hydrothermal decomposition. The 2D MXene/A-TiO 2 composite exhibits high catalytic activity in the adsorption and desorption of hydrogen kinetics for NaAlH 4 . The critical dehydrogenation temperature of NaAlH 4 is ∼90 °C. The first-stage dehydrogenation (∼3.0 wt.%) is accomplished in 50 min at 110 °C. After the first activated cycle, a constant cycling capacity of 4.7 wt.% is remained for a minimum of five cycles tests. It is found that the excellent catalytic activation should be ascribed to the synergistic effect between homogenous distributed Ti-H and TiC, which are originated from MXene/A-TiO 2 . The results represent a new step forward in the applications of MXene catalytic dehydrogenation and provide new strategies in the quest for new functional MXene derivatives by in-situ modification.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2012
·
IF 3.461
C. Shen,Y.J. Wang,J.H. Xu,G.S. Luo
This paper presents a novel immobilization method for the preparation of highly dispersed TiO 2 nanoparticles supported on porous glass beads. The method involves an in situ ion exchange process and a calcination process. Mono-dispersed TiO 2 nanoparticles exhibiting the anatase phase with different mean diameter and different loading amount have been successfully prepared through the controllable and green way. With the increase of loading amount of Ti from 0.08 wt.% to 4.55 wt.%, the mean diameter of the TiO 2 nanoparticles varied from 3.8 to 5.3 nm. And the band gaps of the TiO 2 nanoparticles with the highest and lowest loading amount are 3.25 and 3.00 eV, respectively. The prepared TiO 2 nanoparticles supported on porous glass beads showed excellent photocatalytic performance for the degradation of methyl orange (MO). For the catalyst with a Ti content of 0.08 wt.%, when the dosage was 1.93e−5 g/mL, 65% of the total MO decomposed after 30 min; for the catalyst with a Ti content of 2.56 wt.%, when the dosage reached 0.81e−3 g/mL, complete degradation was observed.
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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Zhong Li,Azhar Ali Haidry,BaoXia Dong,LinChao Sun,Qawareer Fatima,LiJuan Xie,ZhengJun Yao
Long range nitrogen doped ordered mesoporous TiO 2 (N-OMT) structures having pore size 3–4 nm and wall thickness ∼2 nm were synthesized via multi-component process and then characterized by XRD , Raman spectra, BET, SEM, TEM , and XPS . Afterwards, powders of N-OMT were sprayed on the ceramic substrates with Au interdigitated electrodes to apply as humidity sensors and conduct systematic dynamic humidity sensing tests under dark conditions and room temperature via a custom-made gas-sensing test system. High resistance variation (>10 5 ) towards 90% RH reveals its high sensitivity and application potential. The results indicate that nitrogen doping and mesoporous structure are synergistically conducive to enhancing the humidity sensing properties and evaporation induced self-assembly (EISA) strategy should be one of the most effective and significant approaches to prepare the higher performance humidity sensing materials. Based on the characterization and analysis, as well as the comparison with other sensors based on OMT and Commercial powders, a reasonable humidity sensing mechanism aim to explain the enhancement of N-OMT sensor's performances is discussed in detail.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Jiapeng Zhang,Jiang Li,Lijing Yang,Ran Li,Fengming Zhang,Hua Dong
Hydrolysis of ammonia borane provides a reliable pathway for hydrogen production , while suitable catalysts are indispensable to make the hydrolysis reaction reach a considerable rate. In the present work, a series of TiO 2 -supported RuCo catalysts have been fabricated by coprecipitation and subsequent reduction of Ru 3+ and Co 2+ on the surface of TiO 2 nanoparticles . Transmission electron microscopy and elemental mapping have verified the good distribution of metal species in the catalysts. The fabricated catalysts have shown excellent performance for catalyzing ammonia borane hydrolysis, especially in alkaline solutions with 0.5 M NaOH. For Ru 1 Co 9 /TiO 2 in which Ru/Co molar ratio is 1:9, the active energy of catalyzed ammonia borane hydrolysis is 33.25 kJ/mol, and a turnover frequency based on Ru as high as 1408 mol H2 /(mol Ru ·min) is obtained at 25 °C. Moreover, when different types of TiO 2 substrates are used, anatase TiO 2 -supported catalysts show better catalytic activity than their counterparts with rutile TiO 2 as substrate or mixture of anatase and rutile TiO 2 as substrate.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Scientific Reports
·
2015
·Vol. 5
·期 1
·1-9
·
IF 5.578
Hou Huilin,Shang Minghui,Wang Lin,Li Wenge,Tang Bin,Yang Weiyou
Currently, Degussa P25, with the typical mixed phases of anatase and rutile TiO 2 , is widely applied as the commercial photocatalysts. However, there are still some of obstacles for the P25 nanoparticles with totally high photocatalytic activities, especially for the catalytic stability due to their inevitable aggregation of the nanoparticles when used as the photocatalysts. In the present work, we reported the exploration of a novel TiO 2 photocatalyst, which could offer an ideal platform for synergetic combination of the mixed-phase composition, hollow architecture and mesoporous walls for the desired excellent photocatalytic efficiency and robust stability. The mesoporous TiO 2 hollow nanofibers were fabricated via a facile single capillary electrospinning technique, in which the foaming agents were used for creating mesopores throughout the walls of the hollow fibers. The obtained hollow fibers exhibit a high purity and possess the mixed phases of 94.6% anatase and 5.4% rutile TiO2. As compared to P25, the as-fabricated mesoporous TiO2 hollow fibers exhibited much higher efficient photocatalytic activities and stabilities toward the hydrogen evolution with a rate of ~499.1 μmol g −1 ·h −1 and ~99.5% degradation Rhodamine B (RhB) in 60 min, suggesting their promising application in efficient photocatalysts.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2016
·
IF 2.628
Yanke Yu,Jinsheng Chen,Jinxiu Wang,Yanting Chen
A series of CuSO 4 /TiO 2 catalysts were prepared using a wet impregnation method. The activity of each sample in the selective catalytic reduction of NO by NH 3 (NH 3 -SCR) was determined. The effects of SO 2 and H 2 O, and their combined effect, on the activity were examined at 340 °C for 24 h. The catalysts were characterized using N 2 adsorption-desorption, X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed reduction of H 2 (H 2 -TPR), temperature-programmed desorption of NH 3 (NH 3 -TPD), and in situ diffuse-reflectance infrared Fourier-transform spectroscopy (DRIFTS). The CuSO 4 /TiO 2 catalysts had good activities, with low production of N 2 O above 340 °C. SO 2 or a combination of SO 2 and H 2 O had little effect on the activity, and H 2 O caused only a slight decrease in activity during the experimental period. The NH 3 -TPD and H 2 -TPR results showed that CuSO 4 increased the amounts of acid sites and adsorbed oxygen on the catalyst. In situ DRIFTS showed that the NH 3 -SCR reaction on the CuSO 4 /TiO 2 catalysts followed an Eley–Rideal mechanism. The reaction of gaseous NO with NH 3 adsorbed on Lewis acid sites to form N 2 and H 2 O could be the main reaction pathway, and oxygen adsorption might favor this process.
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
Bioactive Materials
·
2020
·
IF 8.724
Yawei Ren,Yajing Han,Zhaoyang Li,Xiangmei Liu,Shengli Zhu,Yanqin Liang,Kelvin Wai Kwok Yeung,Shuilin Wu
Bacterial infection and related diseases are threatening the health of human beings. Photocatalytic disinfection as a simple and low-cost disinfection strategy is attracting more and more attention. In this work, TiO 2 nanoparticles (NPs) were modified by co-doping of Ce and Er using the sol–gel method, which endowed TiO 2 NPs with enhanced visible light photocatalytic performance but not pure ultraviolet photocatalytic properties compared the untreated TiO 2 . Our results disclosed that as the doping content of Er increased, the photocatalytic activity of modified TiO 2 NPs initially increased and subsequently decreased. The same trend occurred for Ce doping. When the doping dose of Er and Ce is 0.5 mol% and 0.2 mol%, the 0.5Ce0.2Ti–O calcined at 800 °C presented the best antibacterial properties, with the antibacterial efficiency of 91.23% and 92.8% for Staphylococcus aureus and Escherichia coli , respectively. The existence of Er ions is thought to successfully turn the near-infrared radiation into visible region, which is easier to be absorbed by TiO 2 NPs. Meanwhile, the addition of Ce ions can effectively extend spectral response range and inhibit the recombination of electrons and holes, enhancing the photocatalytic disinfection activity of co-doped TiO 2 .
研究领域:
材料科学
·
微生物学
·
光催化技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Xueying Zhao,Wenyu Xie,Zhibo Deng,Gan Wang,Aihui Cao,Huamei Chen,Bo Yang,Zhuan Wang,Xintai Su,Chao Yang
NiO-TiO 2-x /C composites for photo-catalytic hydrogen production have been prepared by a molten salt template-assisted pyrolysis of Ni/Ti-oleylamine precursors at different temperatures. X-ray diffraction (XRD) analysis shows that it is brookite structure, and X-ray photoelectron spectrum (XPS) determines the chemical state of the elements. Carbon nanosheets improve the dispersion and stability of TiO 2 , making the later fully close to each other. NiO facilitates the separation of photo-generated carriers and enhances the photocatalytic hydrogen production activity of TiO 2 . Due to the efficient synergy of carbon nanosheets, NiO, and TiO 2 , the optimized (1 wt%)NiO-TiO 2-x /C-T650 nanocomposites show enhanced activity toward photocatalytic hydrogen production from water, outperforming 18-fold in activity higher than pristine TiO 2 /C. Moreover, the (1 wt%)NiO-TiO 2-x /C-T650 catalyst exhibits good stability without obvious decrease in activity under continuous cycling. This work will lead to the optimization of carbon-supported multi-component catalysts for photocatalytic hydrogen production.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Hui Mei,Shixiang Zhou,Mingyang Lu,Yong Zhao,Laifei Cheng
For real-time environmental monitoring and gas detection under harsh conditions, gas sensors with high reliability, sensitivity, and selectivity are in increasing demand. Therefore, pine-branch-like α-Fe 2 O 3 /TiO 2 with a core–shell hierarchical heterojunction structure was designed and fabricated for ethanol sensing. The heterojunction increased the O adsorption, resulting in the formation of more chemisorbed O species for reaction with the target gas. Moreover, the pine-branch-like morphology formed three-dimensional hollow holes as channels for molecule diffusion and adsorption. Compared with gas-proof structures, the hollow regions can realize gas diffusion in the inner and outer surfaces of materials simultaneously. Further, in contrast to aggregated structures, the fibers were separated from each other, and charge conduction between the fibers needed to pass through the surface sensing layer at the fiber boundary; thus, the overall resistance change of the sensors was significantly affected by the response of the heterojunction to the target gas. Consequently, the α-Fe 2 O 3 /TiO 2 sensor exhibited a high response value of 40.4 toward 500 ppm ethanol gas and had excellent selectivity to ethanol. The proposed strategy may facilitate the design and construction of effective heterojunctions and nanostructures for gas sensing.
研究领域:
材料科学
·
传感器技术
·
纳米科技
✓ 已验证
产品关联
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2022
·Vol. 49
·期 1
·101-119
·
IF 3.134
Chen Fenghua,Yang Maosen,Shi Xiangdong,Qin Xiaoyun,Chen Qingtao,Jiang Liying,Jia Chunxiao
In order to increase the photocatalytic performance of titanium dioxide mesocrystals (TMCs), in this study, Ag nanoparticles with different mass content were first photodeposited on the surface of as-prepared TMCs to form heterostructured Ag–TMCs catalysts, followed by loading them on g-C 3 N 4 via one step “bottom-to-up” calcination method. The results of photocatalytic degradation toward RhB experiments showed that the prepared ternary photocatalyst of g-C 3 N 4 /Ag–TMCs exhibited excellent photocatalytic activity not only compared with the bare TMCs and Ag–TMCs, but also with all of those reported TiO 2 /Ag/g-C 3 N 4 ternary photocatalysts. Such improved photocatalytic properties were attributed to the synergistic effect created by the LSPR effect and an important role as an electron-conduction bridge of Ag and the existence of heterojunction structure formed between Ag, TMCs and the further coupling g-C 3 N 4 , which added to the evidences that enabled the prepared g-C 3 N 4 /Ag–TMCs catalyst enhanced transfer efficiency of photogenerated carriers and suppressed recombination rate of electron-hole pairs. Moreover, the deposited Ag content had a positive effect on the photocatalytic degradation efficiency. On the basis of the results of this study, the specimen of g-C 3 N 4 /9% Ag–TMCs showed RhB degradation efficiency up to 100% under only 15 min visible-light irradiation. A possible degradation mechanism was also proposed based on several characterizations including photoluminescence spectrum and a serious of photoelectrochemical measurements. Overall, the prepared g-C 3 N 4 /Ag–TMCs ternary photocatalyst with good recyclability looked promising for future practical applications in the visible-light photodegradation of organic pollutants.
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
Catalysis Science & Technology
·
2022
·Vol. 12
·期 23
·7151-7160
·
IF 6.177
Yaxin Zhou,Hao Qin,Sihan Fang,Yangyang Wang,Jun Li,Giuseppe Mele,Chen Wang
Photocatalytic hydrogen production from water is a clean and sustainable way of energy regeneration. Single-atom catalysts (SACs) have received increasing attention in the field of photocatalysis due to their high catalytic activity, selectivity, stability, and 100% atomic utilization. In this work, we utilized TiO2 with oxygen vacancy (Vo-TiO2) to anchor atomically dispersed Pt and Pd, developing a Vo-TiO2-supported dual atomic catalyst (Pt–Pd SAs/Vo-TiO2). Experiments show the metal atomic sites are stabilized by the oxygen vacancy of TiO2, and the Ti–Pt–Ti structure and the Ti–Pd–Ti structure are constructed. The result shows that the hydrogen production rate of Pt–Pd SAs/Vo-TiO2 is 4 times higher than that of Pt–Pd NPs/TiO2, and its hydrogen production rate is as high as 4241.4 μmol h−1 gcat.−1, which greatly reduces catalyst cost and makes photocatalytic water hydrogen production more economical and sustainable. This work provides a new idea for the development of dual single-atom catalysts for efficient photocatalytic hydrogen production.
研究领域:
材料科学
·
光催化
·
能源科学
✓ 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）