ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2022
·
IF 11.357
Zhilin Zhang,Guangzhi He,Yaobin Li,Changbin Zhang,Jinzhu Ma,Hong He
Pt/Al2O3 catalysts showing excellent activity and stability have been used in various reactions, including HCHO oxidation. Herein, we prepared Pt–Na/Al2O3 catalysts with a Pt content of 0.05 wt % to reveal the key factors determining the anchoring of Pt as well as the catalytic activity and mechanism of HCHO oxidation. Pt–Na/nano-Al2O3 (denoted as Pt–Na/nAl2O3) catalysts with 0.05 wt % Pt content could completely oxidize HCHO to CO2 at room temperature, which is the lowest Pt content used in HCHO catalytic oxidation to our knowledge. After Na addition, terminal hydroxyl groups (denoted as HO-μter) on nano-Al2O3 were transformed to doubly bridging hydroxyl groups between Na and Al (denoted as HO-μbri(Na–Al)), which atomically dispersed Pt species. Pt anchoring further promoted the regeneration of HO-μbri(Na–Al) by activating O2 and H2O, oxidizing HCHO to CO2 directly by the fast reaction step ([HCOO–] + [OH]a → CO2 + H2O). Our study revealed that the HO-μbri(Na–Al) synergistically generated by HO-μter and Na species provided anchoring sites for Pt species.
研究领域:
催化化学
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环境科学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2020
·Vol. 11
·期 5
·1914-1921
·
IF 5.721
Xiaoxiao Qin,Xueyan Chen,Min Chen,Jianghao Zhang,Hong He,Changbin Zhang
Formaldehyde (HCHO) elimination at low temperature is of great interest for indoor air purification. In this work, 1 wt% Ru supported on CeO2 and Al2O3 catalysts were prepared by an impregnation method and subsequently tested for the catalytic oxidation of HCHO at low temperature. The activity of the Ru/CeO2 catalyst was significantly superior to the Ru/Al2O3 catalyst, achieving complete conversion of 130 ppm HCHO at 90 °C with a GHSV of 100 000 mL gcat−1 h−1. Brunauer–Emmett–Teller (BET) measurements, X-ray powder diffraction (XRD), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray photoelectron spectroscopy (XPS) and H2-temperature-programmed reduction (H2-TPR) were carried out to characterize the physical and chemical properties of the catalysts. The results revealed that RuOx species, rather than Ru0, were directly responsible for the HCHO oxidation over Ru/CeO2, and the excellent performance of Ru/CeO2 was mainly attributed to the strong interaction between Ru and CeO2, which induced a high dispersion and high redox capacity of RuOx species. The reaction mechanism of HCHO oxidation was also investigated using in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). It was shown that the HCHO oxidation over the Ru/CeO2 and Ru/Al2O3 catalysts followed the same pathway of the direct formate oxidation (HCHO → HCOO + OH → H2O + CO2).
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 Energy Chemistry
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2013
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IF 0
Lipeng Zhou,Beibei Dong,Si Tang,Hong Ma,Chen Chen,Xiaomei Yang,Jie Xu
Sulfonated carbon as a strong and stable solid acid catalyst exhibited excellent catalytic performance in various acid-catalyzed reactions. Here, sulfonated carbon, as catalyst for oxidation reaction, was prepared via the carbonization of starch followed by sulfonation with concentrated sulfuric acid. N 2 physisorption , X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence and acid-base titration were used to characterize the obtained materials. The catalytic activity of sulfonated carbon was studied in the oxidation of aldehydes to carboxylic acids using 30 wt% H 2 O 2 as oxidant. This oxidation protocol works well for various aldehydes including aromatic and aliphatic aldehydes. The sulfonated carbon can be recycled for three times without obvious loss of activity.
研究领域:
化学
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催化科学
✓ 已验证
产品关联
DOI
PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
·
2024
·
IF 4.2
Zhengsheng Mao,Youjia Yu,Gen Ba,Hongmei Zhao,Qifang Shi,Yue Cao,Weiran Xie,Jinsong Zhang,Hao Sun,Feng Chen
Diquat (DQ) poisoning has garnered attention in recent years, primarily due to the rising incidence of cases worldwide, coupled with the absence of a viable antidote for its treatment. Despite the fact that diquat monopyridone (DQ-M) has been identified as a significant metabolite of DQ, the enzyme responsible for its formation remains unknown. In this study, we have identified aldehyde oxidase (AOX) as a vital enzyme involved in DQ oxidative metabolism . The metabolism of DQ to DQ-M was significantly inhibited by AOX inhibitors including raloxifene and hydralazine . The source of oxygen incorporated into DQ-M was proved to be from water through a H2 18 O incubation experiment which further corroborated DQ-M formation via AOX metabolism. The product of DQ-M in vitro generated by fresh rat tissues co-incubation was consistent with its AOX expression. The result of the molecular docking analysis of DQ and AOX protein showed that DQ is capable of binding to AOX. Furthermore, the cytotoxicity of DQ was significantly higher than DQ-M at the same concentration tested in six cell types. This work is the first to uncover the involvement of aldehyde oxidase, a non-cytochrome P450 enzyme, in the oxidative metabolic pathway of diquat, thus providing a potential target for the development of detoxification treatment.
研究领域:
药理学
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毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2018
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IF 3.649
Manman Jin,Jinkai Wang,Bing Wang,Zhenmei Guo,Zhiguo Lv
A simple and eco-friendly approach for green oxidation of aldehydes has been proposed, which employed highly efficient heterogeneous catalysts tungsten-doped modified silica SBA-15 (W-SBA-15) as catalysts and H 2 O 2 as a green oxidant. W-SBA-15 were synthesized by immobilizing tungsten species on modified SBA-15 and first used in the aldehydes oxidation reaction. W-SBA-15-APTS (0.002 g, APTS, a kind of modifier) displayed an equivalent catalytic activity comparable to that of homogenous catalyst (H 2 WO 4 , 0.5 g) and maintained excellent catalytic activity over 20 cycles. The pore diameter, ca . 7.94–9.14 nm, of W-SBA-15 provides a suitable mesoscopic environment for the substrate, and the product can diffuse freely during the oxidation of glutaraldehyde (GA). Effective but different catalytic performance of W-SBA-15 for the oxidation of other aldehydes suggests the universal applicability of W-SBA-15. The possible mechanism of the oxidation state of tungsten species in W-SBA-15-APTS was proposed; tungsten species are not only attached to APTS but also incorporated into the framework of SBA-15.
研究领域:
化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Yimin Zhang,Youhai Cao,Dong Chen,Penglei Cui,Jun Yang
The use of Ionic Liquids (ILs) to enhance the electrocatalytic activity of metal nanoparticles has garnered sustained research interest. However, current strategies involving ionic liquids do not exploit their use and advantages in chemical synthesis of metal nanoparticles. Herein, we demonstrate a straightforward method, which combines the advantages of ILs in nanoparticle synthesis with the potentials of ILs in electrocatalysis , for the synthesis of Pd nanoclusters for electrochemical oxidation of formaldehyde. This method relies on the use of 1-(2′-aminoethyl)-3-methyl-imidazolum tetrafluoroborate ionic liquid as stabilizers to directly generate Pd nanoclusters with average sizes of 1.8 ± 0.3 nm in a reaction medium consisting of water and methanol at room temperature . The electrochemical measurements prove that the ionic liquid-assisted Pd nanoclusters have mass-normalized activity approximately 7 times than that of commercial Pd/C catalysts for the oxidation of formaldehyde.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
·
2021
·Vol. 13
·期 19
·4133-4141
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IF 5.686
Lina Zhang,Bangjie Zhang,Peng Xue,Jiwei Li,Zhun Zhang,Yanling Yang,Shuai Wang,Jingdong Lin,Honggang Liao,Yong Wang,Yali Yao,Shaolong Wan,Haifeng Xiong
Graphical Room temperature oxidation : Pretreatment methods affect the nature of the Pd species and the reactivity of Pd/Al 2 O 3 in formaldehyde oxidation at room temperature. The steam treatment (H 2 O/Ar) increased the metal Pd dispersion, and generated more active hydroxyl groups, leading to the enhanced reactivity in formaldehyde oxidation. A Pd/Al 2 O 3 nanocatalyst was pretreated at 750 °C in air, Ar or H 2 O/Ar, respectively. The effect of these different pretreatments on the active species and reactivity of Pd/Al 2 O 3 in formaldehyde oxidation at room temperature was investigated. The pretreatment was found to affect both the phase transformation of PdO to Pd metal and the Pd dispersion, leading to different catalytic performances. We found that the Pd/Al 2 O 3 nanocatalyst pretreated in both Ar and H 2 O/Ar show 60 % and 100 % formaldehyde conversion at 25 °C, respectively, while the catalyst pretreated in air is not active under the same condition. Pretreatments in both Ar and H 2 O/Ar were found to facilitate the formation of metallic Pd on Pd/Al 2 O 3 catalyst, confirmed by both experiments and calculation based on the function of the equilibrium oxygen pressure and temperature. We further found that the catalyst pretreated in H 2 O/Ar has higher Pd dispersion and more surface OH groups compared to that pretreated in Ar, leading to improved activity in formaldehyde oxidation.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2023
·Vol. 13
·期 4
·663
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IF 3.9
Xu Wu,Heqin Guo,Litao Jia,Yong Xiao,Bo Hou,Debao Li
The base-free oxidation of furfural by non-noble metal systems has been challenging. Although MnO2emerges as a potential catalyst application in base-free conditions, its catalytic efficiency still needs to be improved. The crystalline form of MnO2is an important factor affecting the oxidation ability of furfural. For this reason, four crystalline forms of MnO2(α, β, γ, and δ-MnO2) were selected. Their oxidation performance and surface functional groups were analyzed and compared in detail. Only δ-MnO2exhibited excellent activity, achieving 99.04% furfural conversion and 100% Propo.FA(Only furoic acid was detected by HPLC in the product) under base-free conditions, while the furfural conversion of α, β, and γ-MnO2was below 10%. Characterization by XPS, IR, O2-TPD and other means revealed that δ-MnO2has the most abundant active oxygen species and surface hydroxyl groups, which are responsible for the best performance of δ-MnO2. This work achieves the green and efficient oxidation of furfural to furoic acid over non-noble metal catalysts.Keywords:base-free;MnO2;crystal type;furfural oxidation to furoic acid
研究领域:
催化化学
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Min Chen,Honghong Wang,Xueyan Chen,Fei Wang,Xiaoxiao Qin,Changbin Zhang,Hong He
Photocatalysis is regarded as a promising method for indoor formaldehyde (HCHO) removal, and there remains a strong demand for the development of highly efficient photocatalysts for HCHO oxidation under visible light. Herein, by grafting nano CuO x clusters onto TiO 2 , the higher performance is achieved over Cu-TiO 2 for the photocatalytic oxidation of HCHO under visible light compared with the typical photocatalysts N-TiO 2 and g-C 3 N 4 . It is found that the presence of water greatly promotes the activity of HCHO oxidation on Cu-TiO 2 . The characterization results indicate that the CuO x clusters on TiO 2 exhibit high redox reversibility between Cu (II) and Cu (I) and greatly facilitate the migration of electrons. The mechanism of photocatalytic oxidation of HCHO was explored by using in situ DRIFTS measurements and DFT calculations. It is shown that HCHO is firstly oxidized to dioxymethylene (DOM), and then DOM is transformed into formate species under visible light irradiation. DFT calculations results indicate that the OH species are responsible for surface formate decomposition, which is the rate-determining step, while O 2 − radical is not active in formate decomposition. Our findings improve the understanding on the photocatalytic oxidation of HCHO, and the Cu-TiO 2 catalyst is a promising candidate for practical application in indoor air purification.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2024
·
IF 14
Haoyu Zhan,Baixue Cheng,Yankun Lu,Danning Xing,Xingshuai Lv,Huining Huang,Thomas Frauenheim,Tao Wang,Peng Zhou
Co 3 O 4 possesses both direct and indirect oxidation effects and is considered as a promising catalyst for the oxidation of 5-hydroxymethylfurfural (HMF). However, the enrichment and activation effects of Co 3 O 4 on OH − and HMF are weak, which limits its further application. Metal defect engineering can regulate the electronic structure, optimize the adsorption of intermediates, and improve the catalytic activity by breaking the symmetry of the material, which is rarely involved in the upgrading of biomass. In this work, we prepare Co 3 O 4 with metal defects and load the precious metal platinum at the defect sites (Pt-Vco). The results of in-situ characterizations, electrochemical measurements, and theoretical calculations indicate that the reduction of Co–Co coordination number and the formation of Pt–Co bond induce the decrease of electron filling in the antibonding orbitals of Co element. The resulting upward shift of the d -band center of Co combined with the characteristic adsorption of Pt species synergically enhances the enrichment and activation of organic molecules and OH − species, thus exhibiting excellent HMF oxidation activity (including a lower onset potential (1.14 V) and 19 times higher current density than pure Co 3 O 4 at 1.35 V). In summary, this work explores the adsorption enhancement mechanism of metal defect sites modified by precious metal in detail, provides a new option for improving the HMF oxidation activity of cobalt-based materials, broadens the application field of metal defect based materials, and gives an innovative guidance for the functional utilization of metal defect sites in biomass conversion.
研究领域:
材料科学
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化学工程
·
生物质转化
✓ 已验证
产品关联
DOI
高影响因子
Processes
·
2025
·Vol. 13
·期 5
·1440
·
IF 2.8
Tongtong Zhang,Sijia Wang,Xingyuan Li,Yupeng Du,Jiajun Hu,Shi Jiang,Yu Guo
Room-temperature complete oxidation of formaldehyde (HCHO) is an important orientation of research programs, yet challenges remain. The development of efficient catalysts with high activity and excellent stability is of great significance for such practical application. Inspired by this whole catalytic process, we, therefore, chose HZSM-5 zeolite with abundant acidic sites as catalyst support and lactic acid (LA) as modifier to regulate the properties. The use of LA simultaneously enhances the hydroxyls density and increases the dispersion of Pt nanoparticles, which are better than the reference catalyst prepared via direct wetness impregnation method. Most satisfying of all, the lactic acid-modified HZSM-5-supported Pt catalyst demonstrates a remarkable reaction performance for room-temperature HCHO oxidation at a high concentration HCHO of 80 ppm and a large space velocity of 360,000 mL/g/h (especially with a low Pt loading of 0.5%). In addition, a 120 h test further confirms the favorable stability of the designed catalyst. This pre-modified strategy using organic acid might provide potential approach in the construction of efficient zeolite-supported catalysts.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Communications Chemistry
·
2019
·Vol. 2
·期 1
·1-11
·
IF 0
Sun Xiucheng,Lin Jian,Chen Yang,Wang Yuehan,Li Lin,Miao Shu,Pan Xiaoli,Wang Xiaodong
Minimizing the use of precious metal remains a challenge in heterogeneous catalysis, such as platinum-based catalysts for formaldehyde oxidation. Here we report the catalyst system Pt/TiO 2 with low platinum loading of 0.08 wt%, orders of magnitude lower than conventional catalysts. A volcano-like relationship is identified between reaction rates of formaldehyde and platinum sizes in a scale of single-atoms, nanoclusters and nanoparticles, respectively. Various characterization techniques demonstrate that platinum nanoclusters facilitate more activation of O 2 and easier adsorption of HCHO as formates. The activated O facilitates the decomposition of formates to CO 2 via a lower reaction barrier. Consequently, this size platinum with such low loading realizes complete elimination of formaldehyde at ambient conditions, outperforming single-atoms and nanoparticles. Moreover, the platinum nanoclusters exhibit a good versatility regardless of supporting on “active” FeO x or “inert” Al 2 O 3 for formaldehyde removal. The identification of the most active species has broad implications to design cost-effective metal catalysts with relatively lower loadings.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）