APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Yaru Wang,Jianjun Zhao,Xianqiang Xiong,Shengwei Liu,Yiming Xu
Anatase TiO 2 is the most studied environmental photocatalyst, but its efficiency is still not high enough to enable application. Herein we report a positive effect of Ni 2+ ions on the photocatalytic reaction in neutral aqueous solution. On addition of 1 mM Ni(ClO 4 ) 2 , the rates of phenol oxidation on TiO 2 and 0.5 wt.% Pt/TiO 2 increased by factors of 2.1 and 8.0, respectively. Meanwhile, the formation of organic intermediate was reduced, and the removal of total organic content was enhanced. Interestingly, Ni 2+ concentration did not change with irradiation time. Moreover, a maximum rate of phenol degradation was observed with Ni 2+ ions, occupying half the surface of TiO 2 or Pt/TiO 2 , where Ni(OH) + was more active than Ni(OH) 2 . X-ray photoelectron spectroscopy identified a Ni 3+ species produced in absence of phenol. A (photo)electrochemical study revealed that Ni 2+ oxidation was favored over H 2 O oxidation, whereas Ni 2+ and Pt inhibited and facilitated O 2 reduction, respectively. It is proposed that the adsorbed Ni(OH) + on TiO 2 is oxidized to Ni 3+ by the photogenerated holes of TiO 2 , followed by regeneration through phenol oxidation. The Ni 2+ -catalyzed organic oxidation then promotes the Pt-catalyzed O 2 reduction, and vice visa, resulting into the greatly improved efficiency of charge separation. This work highlights the possibility of Ni 2+ ions as the hole mediator of organic oxidation over a semiconductor.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
CATALYSIS COMMUNICATIONS
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2017
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IF 3.33
Juanjuan Liu,Shihui Zou,Linfang Lu,Hongting Zhao,Liping Xiao,Jie Fan
Pt nanoparticles supported on anatase TiO 2 is an efficient and stable catalyst for room-temperature selective oxidation of benzyl alcohol under base-free aqueous conditions with ambient air as the oxidant. The result shows that the anatase content of support has a big influence on the activity of Pt/TiO 2 . Higher anatase content results in better performance, with optimal activity for Pt/anatase TiO 2 of 76.7 ± 1.5% in conversion and nearly 100% in selectivity to aldehyde within 10 h. Moreover, a quasi-linear relationship between anatase content of the support and the activity of Pt/TiO 2 is observed.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2023
·
IF 2.8
Chunzheng Wu,Ling Fang,Fangjie Ding,Genxiang Mao,Xiaogu Huang,Shun Lu
Ultra-small Pt nanoparticles loaded on TiO 2 through in-situ photo-deposition for H 2 production via photo reforming of wastepaper was prepared in this study. The effect of noble metal cocatalyst, Pt loading, content of paper (e.g., napkin), and concentration of NaOH was investigated. Consequently, a highest H 2 production rate of 614.7 µmol/g/h was achieved in the optimum condition. It was found that both the solid paper and the dissolved part in the NaOH solution could scavenge the photo-generated holes and contribute to H 2 production. Our research provides a potential route for the reuse of wastepaper to produce clean fuel.
研究领域:
环境科学
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能源科学
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材料科学
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产品关联
DOI
高影响因子
Sustainability
·
2023
·Vol. 15
·期 2
·1403
·
IF 3.9
Xueqiao Mei,Han Yuan,Chunhu Li
As the efficient catalysts are synthesized by a simple strategy, photocatalysis offers a sustainable route to solve the problem of environmentally sound treatment of industrial dye wastewater. Herein, Pt-doped TiO2with MIL-125 as the backbone has been fabricated using thermal synthesis. The photocatalytic efficiency of the synthesized catalyst samples was tested using Rhodamine B (RhB) as the contaminant model. The physicochemical properties of the solid specimens were characterized using XRD, SEM, TEM, BET and EDX techniques. The photocatalytic degradation experiments showed that the photocatalytic degradation of RhB by M-Pt-TiO2was 98.97% after 30 min of degradation. The radical capture experiments showed that superoxide radicals and conduction band electrons as reactive oxygen species played a major role in the degradation process. After four cycles, the photocatalytic activity of M-Pt-TiO2decreased from 98.4% to 94.9%, indicating that the photocatalyst sample had good photocatalytic stability.Keywords:metal-organic framework;Pt-TiO2;photocatalysis;dye wastewater;Rhodamine B
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
NEW JOURNAL OF CHEMISTRY
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2022
·Vol. 46
·期 43
·20777-20785
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IF 3.925
Yanke Yu,Mengqiao Geng,Desheng Wei,Chi He
Selective catalytic oxidation of NH3 (NH3-SCO) is a promising method to reduce NH3 pollution. The Pt-based catalysts exhibited excellent activity in the NH3-SCO reaction under low temperatures. However, it was easy for the NH3 to be oxidized to N2O and NOx (NO and NO2) over the Pt-based catalyst, causing a low N2 selectivity. The CuSO4, which could supply both Brønsted and Lewis acid sites on the catalyst, was used to promote N2 selectivity. The N2 adsorption–desorption, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), inductively coupled plasma mass spectrometry (ICP-MS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), NH3-temperature programmed desorption (NH3-TPD), H2-temperature programmed reduction (H2-TPR) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) were used to characterize the catalyst. The addition of CuSO4 could suppress the formation of N2O and NOx, thus the highest N2 selectivity on the catalyst increased from 21.2% to 78.1%. An imide mechanism was the main reaction mechanism on the Pt/TiO2 catalyst. After adding CuSO4, the NH3-SCO reaction over the CuSO4-Pt/TiO2 catalyst mainly followed an i-SCR mechanism where NH3 was oxidized to N2O and NOx, and then the newly formed N2O and NOx were reacted with NH3/NH4+ adsorbed on the Lewis and Brønsted acid sites via an NH3-SCR reaction over the catalyst, and finally N2 was formed. The acid sites performed an important role in the formation of N2 and this work should provide an effective method to promote N2 selectivity in a NH3-SCO reaction.
研究领域:
催化化学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Xin Kang,Jiancong Liu,Dongxu Wang,Chungui Tian,Honggang Fu
CO 2 hydrogenation to hydrocarbons under high space velocity is crucial for industrial applications, but traditional Fe-based catalysts often suffer from the low activity and poor stability. Herein, we report a new tandem catalyst system combining Pt/TiO 2 catalysts with Fe 3 C catalysts for the direct conversion of CO 2 into C 2 -C 4 hydrocarbons under high space velocity. The Pt/TiO 2 component promotes *CO intermediate production with an enhanced Reverse Water-Gas Shift (RWGS) reaction efficiency, providing a highly reactive species for the Fe 3 C catalyst to achieve Fischer-Tropsch synthesis (FTS). By maximizing the contact interface between the Pt/TiO 2 and Fe-based components through a granule mixing configuration, we achieve significant enhancements in both CO 2 conversion rate (24.0 %) and C 2 -C 4 hydrocarbons selectivity (51.1 %) under the gaseous hourly space velocity (GHSV) of 100000 mL g cat −1 h −1 . Besides, excellent stability is achieved by the tandem catalysts with continuous catalysis for up to 80 h without significant decrease in activity. Through modulation of the reduction states of iron oxide, we effectively tune the composition of Fe-based catalyst, thereby tailoring the product distribution. Through this work, we not only offer a promising avenue for reducing CO 2 for efficient CO 2 utilization but also highlight the importance of catalyst design in advancing sustainable chemical synthesis.
研究领域:
催化化学
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环境科学
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能源化学
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
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2018
·
IF 4.521
Xiao Chen,Zhenglong Zhao,Ying Zhou,Qiulian Zhu,Zhiyan Pan,Hanfeng Lu
This study presents an efficient, economic, and simple preparation strategy for Pt/TiO 2 monolith catalysts. Nano-Pt/TiO 2 dispersion liquid with good activity and stability was synthesized by hydrolysis and chemical reduction method. Various Pt/TiO 2 monolithic catalysts were prepared by spraying the dispersion liquid on different substrates. Results of transmission electron microscopy, scanning electron microscopy, N 2 adsorption-desorption, H 2 temperature-programmed and CO oxidation showed that the Pt/TiO 2 nanoparticles with good mesoporous structure and redox properties were highly dispersed on the substrate. The as-prepared 0.5 Pt/TiO 2 cordierite monolithic catalyst with 0.1 wt‰ Pt content exhibited excellent catalytic combustion activity ( T 90 of toluene combustion was 212 ℃), stability (no deactivation was observed during a 120 h test) and firmness (mass loss was 0.11% after 1 h ultrasonic vibration) under experimental conditions. Compared with state-of-the-art methods, this method is more suitable for large-scale production of waste-gas-treated monolith catalysts. And this method meets the concept of energy saving and emission reduction because of its simplicity, high efficiency, environmental friendliness, and high utilization of active components.
研究领域:
环境科学
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催化材料
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产品关联
DOI
高影响因子
FUEL
·
2018
·
IF 4.908
Riyang Shu,Biqin Lin,Chao Wang,Jingtao Zhang,Zhengdong Cheng,Ying Chen
Noble metal catalyst has an outstanding catalytic activity on the hydrodeoxygenation (HDO) process, but its high cost limits large-scale application. Herein, we put forward a novel photochemical method to prepare the highly dispersed Pt/TiO 2 catalyst with a low metal loading. And it presented an efficient performance on the HDO of phenolic compounds and real bio-oil. Guaiacol could be converted into cyclohexane with 95.1% selectivity at 280 °C under 1 MPa H 2 atmosphere. Characterization results revealed that the high Pt dispersion was the critical factor for the high catalytic activity. And the photochemical method preferred to achieve high metal dispersion due to the room temperature condition. Other typical phenolic monomers and dimers were able to transform into hydrocarbons with most yield above 80%, wherein not only the deoxygenation step, but also the cleavage of ether bonds can be realized in one pot. This catalytic system was also effective on the upgrade of bio-oil derived from the pyrolysis of cotton straw. Hydrocarbon content increased to 33.80% from 11.33%. Alkylphenols content increased to 51.38% from 27.86%. These two products can be used as value-added fuels and chemicals, respectively. Guaiacols and syringols were completely converted into alkylphenols and hydrocarbon. The amount of other oxygenated compounds also decreased significantly. This simple and active catalytic system is potential to apply widely for the upgrade of raw bio-oil.
研究领域:
催化化学
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可再生能源
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2016
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IF 3.15
Fuying Li,Quan Gu,Yu Niu,Renzhang Wang,Yuecong Tong,Shuying Zhu,Hualei Zhang,Zizhong Zhang,Xuxu Wang
Pt nanoparticles were loaded on anatase TiO 2 by the photodeposition method to investigate their photocatalytic activity for H 2 evolution in an aqueous solution containing a certain amount of ethylene glycol (EG) as the sacrificial agent. The surface properties and chemical states of the Pt/TiO 2 sample were characterized by X-ray powder diffraction analysis, Brunauer–Emmett–Teller surface area analysis, transmission electron microscopy, X-ray photoelectron spectroscopy, electron paramagnetic resonance, and electrochemical resistance. The aqueous-phase photocatalytic EG reforming using Pt/TiO 2 and anatase TiO 2 generated not only H 2 and CO 2 , but also CO, CH 4 , C 2 H 6 , and C 2 H 4 . Moreover, the amount of formate and acetate complexes in the solution increased gradually. The EG adsorption and gas-phase intermediates during photocatalytic reaction processes were investigated by the in situ FTIR spectrum. Finally, the photocatalytic EG reforming reaction mechanism was elucidated. This helped to better understand the role of a sacrificial agent in a photocatalytic hydrogen production.
研究领域:
材料科学
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化学工程
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环境科学
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DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2021
·
IF 5.706
Chenglin Feng,Xiaolong Liu,Tingyu Zhu,Yutao Hu,Mengkui Tian
Anatase TiO 2 loaded with 0.1wt.% Pt catalyst (0.1Pt/TiO 2 -A) was prepared via the impregnation method, and its CO catalytic oxidation activity was investigated. Noteworthy, introduction of H 2 O into the reaction atmosphere apparently facilitated the catalytic oxidation of CO. Besides, introduction of SO 2 inhibited the catalytic oxidation of CO. In presence of H 2 O and SO 2 , 0.1Pt/TiO 2 -A showed outstanding catalytic stability, and X-ray photoelectron spectroscopy (XPS) and thermogravimetric (TG) characterizations suggested that the amount of sulfate species deposited on the 0.1Pt/TiO 2 -A treated at 230 °C did not increase with time extension, which might be an important reason for the high sulfur resistance of 0.1Pt/TiO 2 -A. XPS results also demonstrated that the dissociation of H 2 O led to considerably increase of hydroxyl groups over the catalyst surface. H 2 18 O isotope-labeling experiments unambiguously showed that C 16 O 18 O was the main product accounting for 88.9%, revealing that the other oxygen atom in the product CO 2 was mostly from H 2 O. Consequently, based on previous researches and our experimental results, the mechanism of H 2 O promoting CO oxidation on 0.1Pt/TiO 2 -A catalyst was proposed.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
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2020
·
IF 5.627
Fuchang Gao,Zuwei Xu,Haibo Zhao
In this paper, flame spray pyrolysis (FSP) is used to synthesize Pt/TiO 2 catalysts with surface-supported isolated Pt atoms through elaborate precursor/solvent formulation and flame temperature history control. It is a pivotal factor to this FSP process that there is a major distinction on saturated vapor pressure between two components (Pt species and Ti species), and thereby they exist as gas phase and particle phase at a certain temperature range, respectively. When the flame is quenched to ambient temperature with cold sheath gas , Pt species of gaseous PtO 2 (being in the vapor phase above 723 K) condense into deposition state on the surface of TiO 2 nanoparticles . Combined with X-ray photoelectron spectroscopy (XPS) analysis and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) detection, we identify that Pt atoms are dispersed and anchored on the catalyst surface . Single-atom Pt dispersed Pt/TiO 2 catalysts can be well achieved by controlling the loading at a very low level, which offers an effective way to maximize the atom economy for surface catalysis of scarce noble metals. In this work, considering that Pt as the best co-catalyst of hydrogen evolution, the FSP-made Pt/TiO 2 catalysts are tested in a photocatalysis water splitting system aiming to a simple and attractive means of renewable hydrogen production . The highest activity presents in 0.1Pt/TiO 2 with 0.1% molar ratio of Pt to Ti, reaching 108.5 times of the benchmark sample from commercial flame-made TiO 2 (P25). The high activity is attributed to the fact that the isolated Pt atom serves as the main active site for photocatalysis hydrogen evolution. Therefore, the performance and cost efficiency of catalysts are greatly improved by the FSP, mainly ascribed to engineering atomically dispersing Pt on the support surface.
研究领域:
材料科学
·
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Progress in Natural Science-Materials International
·
2024
·
IF 4.8
Danyang Li,Yongqi Li,Dagui Liao,Mengqing Cao,Lulu Zhang,Shasha Zhang,Ling Chen,Yawen Chen,Huan Wang,Jian Qi,Feifei You
Utilizing solar energy to decompose tetracycline (TC) is a green strategy to treat wastewater. Herein, a heterogeneous hollow structured TiO 2 decorated Pt nanoparticles were successfully designed and synthesized via hard-template approach and photo-deposition process toward TC photodegradation . The Pt nanoparticles loaded on the surface of hollow structured TiO 2 can increase the visible light absorption due to the local surface plasmon resonance (LSPR) effect. Furthermore, owing to the tough electron oscillation of the LSPR excitation, the plasmonic hot holes on the surface of Pt nanoparticles can capture the electrons of TiO 2 , effectively facilitating the separation of photo-excited charge carriers because of the formation of Schottky junction constructed between Pt and TiO 2 . Combined the natural merits of shorten conveying path of charge carriers and physical structural stability for hollow structure, the optimal Pt/TiO 2 hetero-junction hybrid showed superior photocatalytic activity and durability for TC photodegradation with the degradation efficiency of 93.8 % after 30 min and the rate constant of 0.09196 min −1 under 300 W Xe lamp irradiation. This work displays a heterogeneous hybrids catalyst based on eco-friendly metal and semiconductor materials which can be used in the fields including without limitation TC photodegradation.
研究领域:
环境科学
·
材料科学
✓ 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）