Journal of Materials Chemistry A
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2023
·Vol. 11
·期 45
·24644-24650
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IF 11.9
Dongrun Xu,Weiye Qu,Junhong Liu,Junxiao Chen,Xue Fang,Liwei Chen,Zhen Ma,Xi Liu,Xingfu Tang,Yaxin Chen
Selective catalytic reduction (SCR) is the most effective technology to control NO emission using commercial V2O5–WO3/TiO2 catalysts, but the nature of active catalytic sites remains under debate. Here we provide evidence demonstrating that dinuclear vanadium–tungsten sites are the most active catalytic sites of conventional V2O5–WO3/TiO2 catalysts, inconsistent with a prevailing view that dimeric vanadium sites are the active sites. The dinuclear vanadium–tungsten sites have inherently stronger acidity than the dimeric vanadium sites, favoring NH3 adsorption. Meanwhile, the vanadium 3d electrons of the dinuclear vanadium–tungsten sites are richer than those of the dimeric vanadium sites, facilitating O2 activation in SCR. Hence, the dinuclear vanadium–tungsten sites have higher SCR activity than the dimeric vanadium sites under identical reaction conditions. This work settles a long dispute on the identification of active sites of conventional V2O5–WO3/TiO2 SCR catalysts, thus having implications for a unified explanation of disparate SCR reaction mechanisms and rational design of improved SCR catalysts.
研究领域:
催化化学
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环境化学
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材料科学
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化学工程
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DOI
高影响因子
HYDROMETALLURGY
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2019
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IF 3.465
Wenbo Lou,Yang Zhang,Shili Zheng,Ping Li,Ying Zhang,Yi Zhang,Bo Zhao,Zhefei Li,Wei Jin
China generates a large number of scrapped selective catalytic reduction (SCR) catalysts in the fossil fuel combustion plants every year. As a result, there is a giant quantity of 5 × 10 5 t scrapped V 2 O 5 -WO 3 /TiO 2 SCR catalyst annually worldwide, in which arsenic poisoning is a major cause of catalysts deactivation . In this study, a novel cleaner recovery process of alkaline-acid stepwise leaching was proposed for the high‑arsenic scrapped SCR catalysts to achieve excellent arsenic removal and structural reforming. It is found that arsenic can be completely removed from 1.92% to below the detection limit, and the surface area of regenerated catalysts is restored to 31 m 2 /g (similar to that of commercial catalysts). In the subsequent pickling and regeneration, Na + can be eliminated to obtain anatase-type TiO 2 for further activity recovery. Besides, valuable elements (W, V) have been successfully recycled by leaching the As-containing solid waste with ammonium salt. After replenishing active components, regenerated catalyst exhibits comparable activity with the commercial fresh catalyst, offering a promising method for scrapped catalyst recovery and further understanding of cleaner produces for waste management .
研究领域:
环境科学
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化学工程
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DOI
高影响因子
CATALYSIS LETTERS
·
2022
·Vol. 152
·期 12
·3594-3606
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IF 2.936
Yao Haoyang,Xu Yunlan,Zhong Dengjie,Zeng Yundong,Zhong Nianbing
In order to inhibit rapid recombination of electron–hole pairs of photoanode and expand its light response wavelength, PPy-14%/WO 3 /TiO 2 /Ti photoanode was prepared. The maximum photocurrent density is 2.31 mA·cm −2 , which is 1.76 times higher than that of WO 3 /TiO 2 /Ti at 1.1 V (vs. SCE). The maximum power density, phontocurrent density and Rhodamine B degradation rate of photocatalytic fuel cell (PFC) with PPy-14%/WO 3 /TiO 2 /Ti photoanode and Cu cathode are 25.48 μW·cm −2 , 0.25 mA·cm −2 and 88.5%, respectively. The excellent performance is mainly due to the good carrier migration rate of PPy and the synergistic effect of PPy/WO 3 /TiO 2 /Ti ternary hybrid electrode, so that photogenerated electrons and holes can accumulate in the conduction band of WO 3 and HOMO of PPy, respectively. This not only expands the light absorption range and enhances the light absorption intensity, but also improves the separation of electron–hole pairs, and finally significantly enhances the Rhodamine B degradation and electricity generation performance of PFC. Graphical Abstract In order to inhibit rapid recombination of electron–hole pairs of photoanode and expand its light response wavelength, PPy-14%/WO 3 /TiO 2 /Ti photoanode was prepared. The excellent performance is mainly due to the good carrier migration rate of PPy and the synergistic effect of PPy/WO 3 /TiO 2 /Ti ternary hybrid electrode, so that photogenerated electrons and holes can accumulate in the conduction band of WO 3 and HOMO of PPy, respectively.
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
Catalysts
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2021
·Vol. 11
·期 11
·1349
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IF 4.146
Liaochuan Jiang,Xingyuan Gao,Shaoling Chen,Jangam Ashok,Sibudjing Kawi
At present, TiO2is one of the most widely used photocatalytic materials. However, the narrow response range to light limits the photocatalytic performance. Herein, we reported a successful construction of self-doped R-WO3/R-TiO2/CC nanocomposites on flexible carbon cloth (CC) via electrochemical reduction to increase the oxygen vacancies (Ovs), resulting in an enhanced separation efficiency of photo-induced charge carriers. The photocurrent of R-WO3/R-TiO2/CC at −1.6 V (vs. SCE) was 2.6 times higher than that of WO3/TiO2/CC, which suggested that Ovscould improve the response to sunlight. Moreover, the photocatalytic activity of R-WO3/TiO2/CC was explored using methylene blue (MB). The degradation rate of MB could reach 68%, which was 1.3 times and 3.8 times higher than that of WO3/TiO2/CC and TiO2/CC, respectively. Furthermore, the solution resistance and charge transfer resistance of R-WO3/R-TiO2/CC were obviously decreased. Therefore, the electrochemical reduction of nanomaterials enabled a promoted separation of photogenerated electron–hole pairs, leading to high photocatalytic activity.Keywords:photocatalysis;electrochemical reduction;photocatalytic degradation;TiO2;WO3
研究领域:
材料科学
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环境科学
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2021
·
IF 9.229
Guanyu Liu,Huiyun Xia,Wenshuo Zhang,Lei Lang,Haipeng Geng,Lifang Song,Yanhui Niu
In recent years, superamphiphobic coatings have been widely used in industrial transportation and environmental treatments because of their unique liquid repellency. In this study, WO3-TiO2 nanorods/SiO2 were used as the constructor of surface microstructures, and 1H,1H,2H,2H-perfluorodecyltriethoxysilane was used as the provider of low surface energy, and a photocatalytic superamphiphobic coating (FTS coating) was prepared. The microstructure and chemical composition of the coating was characterized by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The coating exhibited excellent photocatalytic activity toward degradation methyl red and nitric oxide (NO), and the degradation efficiency to NO reached 47.8%. Also, the advanced contact angle and the hysteresis angle of water, glycol, glycerol, and olive oil was used to evaluate the superamphiphobicity. After 7 days of ultraviolet (UV) aging, five cycles of airbrush flushing and 48 h of immersion in acid, salt, and alkali solutions, the FTS coating still exhibits excellent amphiphobicity, which lays a foundation for its large-scale applications in the concrete exterior wall. The surface microstructure and the formation of air pockets are a prerequisite for superamphiphobicity, which promotes the liquid on the coating surface into the Cassie-Baxter state. Furthermore, the formation of air pockets is closely related to the gas adsorption capacity and the specific surface area (SBET) of the surface microstructure on the coating surface. The coatings with different SBET constructed and the advanced contact angle were measured. The influence of air pockets on the superamphiphobicity of coatings was studied in combination with the optical microscope. The understanding that SBET further influences superamphiphobicity by affecting the surface air pockets is proposed.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
Chemical Physics Impact
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2022
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IF 0
Yanke Yu,Mengqiao Geng,Jiahang Li,Jingjing Wang,Desheng Wei,Chi He
Commercial V 2 O 5 -WO 3 /TiO 2 (VWTi) catalysts used in NH 3 -SCR reaction with varied Zn loading were prepared and then effect of SO 2 on Zn-poisoned VWTi catalysts was investigated. Zn could cause the deactivation of VWTi catalysts. Nevertheless, the effect of SO 2 on Zn-poisoned VWTi catalysts varied with Zn loading. For Zn-poisoned catalyst with low content of Zn (1.0 wt.%, ZnL), SO 2 would promote the activity recovery of the catalyst. However, SO 2 had no influence on the Zn-poisoned catalyst with high Zn content (4.0 wt.%, ZnH). The catalyst was characterized by N 2 adsorption-desorption, XRD, XPS, SO 2 -TPD, NH 3 -TPD, H 2 -TPR and in situ DRIFTS. Tri-coordinated sulfate species were formed on ZnL sample in the presence of SO 2 , and the sulfate species could form new Brønsted acid sites, causing the recovery of activity. But ZnSO 4 was appeared and no Brønsted acid sites formed on ZnH sample under SO 2 , thus the activity of ZnH sample changed little.
研究领域:
催化化学
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环境科学
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DOI
CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Xuesong Liu,Peng Jiang,Yong Chen,Yaoguang Wang,Qiaoling Ding,Zhiming Sui,Hongfeng Chen,Zhongyun Shen,Xiaodong Wu
Two Ce-W-Ti mixed oxide catalysts were prepared by wet impregnation (CeW/Ti-I) and mechanical mixing (Ce/W/Ti-M) methods. CeW/Ti-I catalyst exhibits over 80% NO x conversion and nearly 100% N 2 selectivity at 200–550 °C. The superior catalytic performance is associated with the high dispersion of active CeO 2 and acidic WO 3 on TiO 2 and the synergistic effects among different components. The X-ray Diffraction, Raman spectroscopy, Nitrogen physisorption, X-ray photoelectron spectroscopy, H 2 temperature-programmed reduction, temperature-programmed desorption of ammonia and infrared spectroscopy were performed. It is found that the formation of solid solutions, as well as the high specific surface area, would increase the amounts of Ce 3+ , oxygen vacancies and acid sites in the catalyst. These broaden the operating temperature window of NH 3 -SCR reaction and enhance the N 2 selectivity by facilitating “fast SCR” reaction at low temperatures and inhibiting the unselective oxidation of NH 3 at high temperatures.
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
CATALYSIS LETTERS
·
2019
·Vol. 150
·期 2
·375-383
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IF 2.372
Liu Xiaolong,Zhao Ziwei,Ning Ruliang,Qin Yu,Zhu Tingyu,Liu Fagao
The promoting effect of Ce on V-W/Ti catalyst for selective catalytic reduction (SCR) of NO x by NH 3 was studied. Compared with the original V-W/Ti samples, addition of Ce contributed better NH 3 -SCR performance. The H 2 O and SO 2 resistance of Ce modified V-W/Ti catalyst was improved by the different impregnation sequence of Ce. The catalysts were characterized by NH 3 -temperature programmed desorption (NH 3 -TPD), X-ray photoelectron spectroscopy (XPS), and H 2 -temperature programmed reduction (H 2 -TPR) techniques. The results showed that the impregnation sequence of W and Ce influenced the NH 3 adsorption capacity of the catalysts. In comparison to 0.2V-5Ce-5W/Ti and 0.2V-(5Ce5W)/Ti, 0.2V-5W-5Ce/Ti catalyst contributed better H 2 O and SO 2 resistance, with the highest Ce 3+ /(Ce 4+ + Ce 3+ ) value of 36.6%. Besides, a catalytic mechanism of SCR reactions over Ce-doped V-W/Ti catalysts was proposed. Graphic
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DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
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2026
·
IF 2.1
Lin Daifeng,Gong Wanyu,Lu Zeyang,Zhuo Qian,Yang Wenqing
Herein, Ru-doped V 2 O 5 -WO 3 /TiO 2 (VWTi) catalysts were prepared to study the impact of Ru doping on chlorobenzene (CB) oxidation activity. The introduction of Ru weakens the V–O bond strength, resulting in neutralizing the Lewis acid effect and optimizing the overall acid balance of the VWTi catalyst. Moreover, the presence of RuO 2 can significantly enhance the redox capability and surface lattice oxygen mobility. Hence, a significant improvement in both low-temperature activity and CO 2 selectivity has been achieved with the Ru-doped VWTi catalyst, reaching a CB conversion of 50% at 205 °C and a CO 2 selectivity of 73% at 400 °C for 0.50Ru-VWTi catalyst.
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高影响因子
Catalysts
·
2020
·Vol. 10
·期 2
·207
·
IF 3.52
Hua Nie,Wei Li,Qirong Wu,Vladislav Rac,Vesna Rakić,Xuesen Du
Poisoning effects by alkali metal chlorides is one of the major reasons for the deactivation of SCR catalyst in biomass-fired plants. In this study, the influence of KCl on two vanadium-based catalysts with different promoters, V2O5-WO3/TiO2and V2O5-Ce(SO4)2/TiO2, was investigated. The catalytic activity of the fresh V2O5-WO3/TiO2was higher than that of V2O5-Ce(SO4)2/TiO2at low temperatures. V2O5-Ce(SO4)2/TiO2performed better than V2O5-WO3/TiO2when KCl was deposited on the catalyst surface. Both poisoned catalysts were efficiently regenerated by SO2treatment. The characterization results show that the reducibility and acidity of the catalysts were weakened by KCl deposition but regenerated by SO2.
研究领域:
环境催化
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大气污染控制
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材料化学
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工业催化
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能源工程
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
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2024
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IF 5.2
Wenbo Jia,Yueyuan Wang,Shaohua Ling,Liren He,Binghe Chen,Songtao Liu,Chuanmin Chen,Yue Cao
Fast selective catalytic reduction (SCR) atmosphere can significantly improve the NOx removal activity of VWTi catalysts, while the catalytic performance and reaction pathway of Hg0 oxidation in a fast SCR atmosphere are still unclear. In this paper, the catalytic activity of simultaneous NOx removal and Hg0 oxidation over VWTi catalysts in a simulated fast SCR atmosphere was investigated for the first time. The results showed that VWTi catalysts possessed a wide NOx removal active temperature window and a high Hg0 oxidation activity in a fast SCR atmosphere. The X-ray photoelectron spectroscopy (XPS) and Hg temperature-programmed desorption (Hg-TPD) methods were used to investigate the Hg0 oxidation process over VWTi catalysts in a fast SCR atmosphere. Combined with the homogeneous Hg0 oxidation experiment results, two domination reaction routes of Hg0 oxidation over VWTi catalysts in a fast SCR atmosphere were proposed. One was that the adsorbed Hg0 could react with the surface active species to form HgO. The other reaction route was a gaseous homogeneous route that the gaseous Hg0 could be oxidized directly to Hg(NO3)2 by gaseous NO2. Particularly, the gaseous homogeneous Hg0 oxidation process could notably weaken the inhibition effect of NH3 on Hg0 oxidation, thus improving the Hg0 oxidation activity of VWTi catalysts in a fast SCR atmosphere.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
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2022
·
IF 6.267
jialong Kang,Zhenyun Tian,Dapeng Zhong
The abundant metal Ti is a high-quality metal with lightweight, high strength, and corrosion resistance. However, due to its harsh preparation conditions, the price remains high, so titanium metal's simple and effective products have become a challenge for the world's scientific research community. In this paper, by calculating the oxygen potential of Ti–O, Ti–H, and Ti–H–O solid solutions, the oxygen potential of Ti–H–O was obtained when the oxygen content was 0.03 and 0.009. As H 2 enters the Ti–O lattice, the oxygen potential of the Ti–H–O system increases with the increase of H content. Thermodynamic calculations showed that introducing hydrogen effectively destroyed the stability of Ti–O solid solutions. At the same time, this paper uses a magnesiothermic as a reducing agent. To verify the feasibility of the above thermodynamics, reduce the spent V 2 O 5 –WO 3 /TiO 2 catalyst (Ti > 80 wt%) of titanium-rich materials in a hydrogen atmosphere. Finally, the spent V 2 O5–WO 3 /TiO 2 catalyst was reduced at 750 °C for 8–24 h to obtain TiH 2 powder with an oxygen content of 0.9 wt%.
研究领域:
材料科学
·
冶金工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）