DALTON TRANSACTIONS
·
2024
·
IF 3.5
Zihao Hu,Xiaoying Zhou,Tiantian Zhang,Zuliang Wu,Jing Li,Wei Wang,Erhao Gao,Jiali Zhu,Shuiliang Yao
Aiming at the problem of the poor performance of an Mn-MOF-74-derived Mn3O4 catalyst in low-temperature carbon monoxide (CO) oxidation, copper (Cu) and cerium (Ce) elements were used to modify the Mn3O4 catalyst to improve its performance in low-temperature CO oxidation. According to the results of catalytic performance testing, the CO oxidation activity of the Cu0.3Mn2.7O4 catalyst was significantly improved compared with that of the pristine Mn3O4 catalyst, when a CO conversion rate of 90% was achieved at 118 °C. According to X-ray photoelectron spectroscopy and Brunauer–Emmett–Teller analyses, the (Mn2+ + Mn3+)/(Mn2+ + Mn3+ + Mn4+) ratio and the Oads/Ototal ratio increased after Cu doping, indicating promoted oxygen vacancy generation. In addition, the increased specific surface area was beneficial for the adsorption of reactant molecules and the exposure of active sites. According to H2-temperature-programmed reduction characterization, Cu doping significantly enhanced the performance of the Cu0.3Mn2.7O4 catalyst during low-temperature redox. Finally, these factors synergistically promoted the degradation of CO over the Cu0.3Mn2.7O4 catalyst. In addition, operando diffuse reflectance Fourier transform infrared spectroscopy results suggested the presence of more terminal-type oxygen, which is essential for the catalytic oxidation of CO on the surface of the Cu0.3Mn2.7O4 catalyst. Moreover, the Cu0.3Mn2.7O4 catalyst also showed excellent resistance to carbonate, and remarkable stability.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2021
·
IF 6.609
Yatao Yang,Xiaoxiao Ding,Kangkai Chang,Zequan Zeng,Yaqin Hou,Zhanggen Huang
Emission of polychlorinated dibenzop-dioxins and polychlorinated dibenzofurans (PCDD/Fs) have exerted more and more pressure on humans and the environment. The catalytic oxidation has been a good selection for eliminating dioxin in industries. Carbon-based catalysts were great potential to alleviate dioxin because of their large surface area and low cost. Catalytic oxidation of dioxin over metal oxide catalysts M/AC (M = V, Fe, Cu, Mn) was evaluated, and V/AC showed the highest catalytic activity at 300 °C. The catalysts surface acid amounts were improved through loading metal oxide, especially the Lewis acid, which could promote DBF adsorption on catalysts. Combined in-situ FTIR with GC–MS, two different reaction paths were provided on V/AC and Cu/AC catalyst. The C–C bond of DBF was priority broken to be oxidized on V/AC, and main transformation of DBF was from benzofuran, phenol and maleic acid to final products. The C–H bond of DBF was firstly activated on Cu/AC, and large unstable quinone species were produced. The main transformation of DBF was from DBF- quinone, benzofuran, furan to final products on Cu/AC. In this work, detailed reaction paths and by-products of DBF oxidation were provided.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2018
·
IF 3.956
Shanshan Shao,Huiyan Zhang,Rui Xiao,Xiaohua Li,Yixi Cai
To understand the evolution of coke in the catalytic conversion of biomass-derivates, in - situ diffuse reflectance Fourier transform infrared spectroscopy experiments and ex - situ extraction method were combined to identify the coke species. Considering the ring-shape and unsaturation of furan as an important intermediate from biomass pyrolysis , other simplified biomass-derivates like tetrahydrofuran , butanol , ethylene glycol and methanol was also studied to investigate the effect of its chemical structure on coke formation. The ex - situ study showed that the performance in the induction period and deactivation stage was closely related to the functional group of biomass-derivates. Coke extraction of furan and tetrahydrofuran were of similar composition , which was of doubt. Combined results with in - situ diffuse reflectance Fourier transform infrared spectroscopy revealed that polymethyl benzaldehyde was the main composition of active coke in the catalytic conversion of furan, and then intermediate of benzofuran was detected, and finally alkyl naphthalene and polyaromatic hydrocarbons were formed by polymerization and hydrogen transfer . This study will provide guidelines to enhance hydrocarbon production from the viewpoint of active coke like pre-feeding of polymethyl benzaldehyde.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2022
·
IF 11.072
Yuhai Sun,Jingyi Han,Kai Xu,Keying Wu,Wei Wu,Xu Zhang,Boqiong Jiang
Aromatic ring-opening process is considered as the rate-determining step for catalytic toluene decomposition. However, the ring-opening pathway has not been fully revealed, especially the effect of the surface species in plasma catalytic hybrid system. Herein, a series of Mn based catalysts (with the low Mn content of 1 wt %), Mn/γ-Al 2 O 3 , Au-Mn/γ-Al 2 O 3 and Ag-Mn/γ-Al 2 O 3 , were used to clarify the mechanism of plasma catalytic toluene degradation by a closely combined temperature-programmed desorption (TPD) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Effects of plasma on surface oxygen species were investigated by a comparison study of O 2 -TPD and plasma-excited O 2 -TPD. A strong interaction between plasma and Ag-Mn/γ-Al 2 O 3 could make better use of plasma-induced active oxygen species ( i.e. O 3 , O*, O 2 * etc. ) and considerably increase the amount of chemically adsorbed oxygen. Moreover, modified NH 3 -TPD experiments proved that O 2 excited by plasma would greatly change the surface acidity of Ag-Mn/γ-Al 2 O 3 , resulting in the desorption activation energy (E d ) of toluene increasing to 19.5 kJ/mol. Finally, possible ring-opening mechanisms over different catalysts were proposed after the evolution of typical intermediates being systematically analyzed by in situ DRIFTS. It was found that the toluene ring-opening reaction on different catalysts might be selectively started at hydroquinone. The present work could provide both a more detailed toluene ring-opening process and new insights into the understanding of the plasma exciting effect on the surface species in VOCs decomposition.
研究领域:
催化
·
等离子体化学
·
环境科学
·
表面科学
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2021
·
IF 8.001
Yuewen Shao,Junzhe Wang,Kai Sun,Guoming Gao,Chao Li,Lijun Zhang,Shu Zhang,Leilei Xu,Guangzhi Hu,Xun Hu
Pentanediols (1,2-pentanediol and 1,5-pentanediol) are important feedstock for synthesis of fine chemicals, production of which from the biomass-derived furfural or furfuryl alcohol (FA) has been considered as a sustainable route and attracted much interest. In this study, the catalysts with Ni–Fe as the metal sites and Mg–Al layered double hydroxides (LDH) as precursor of support were synthesized. The results showed that the presence of Fe in catalyst affected both the development of the pores of the catalyst and the catalytic behaviors of nickel species. A low Fe content facilitated formation of mesoporous structure, but the higher content destroyed the LDH structure, resulting in a decreased surface area. Fe could also react with metallic Ni to form NiFe alloy. This decreased the catalytic activity for the further hydrogenation of the furan ring in FA, and FA would thus have the chance to produce pentanediols via hydrogenolysis . The In-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy characterization of hydrogenation of FA indicated that the alloying between Fe and Ni resulted in a weak adsorption of C C group in furan ring and moderate adsorption of C–O–C group, which suppressed the complete hydrogenation of FA while facilitated the ring-opening of FA to form the pentanediols.
研究领域:
化学工程
·
催化
·
可持续化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Jinping Zhong,Yikui Zeng,Dongdong Chen,Shengpeng Mo,Mingyuan Zhang,Mingli Fu,Junliang Wu,Zixue Su,Peirong Chen,Daiqi Ye
Series of Co 3+ -rich spinel Co 3 O 4 catalysts were synthesized and evaluated by toluene catalytic oxidation. An outstanding activity was achieved over Co 3 O 4 -N utilizing Co(NO 3 ) 2 ·6H 2 O as precursor (T 50 = 211 °C, T 90 = 217 °C at conditions: 1000 ppm(v), WHSV = 60 000 mL g −1 h −1 ). Results of comparative characterizations demonstrated that such excellent performance was mainly attributed to large surface area, high reducibility at low temperature, high abundance of Co 3+ ions and structure defects, as well as highly active surface oxygen. The results of in situ DRIFTS revealed that in the air or N 2 atmosphere, the by-products were almost the same. The reaction pathway of toluene oxidation can be described as follow: transformation of toluene from benzyl alcohol, benzaldehyde, benzoate, benzene, phenol, benzoquinone, maleic acid and to final products, which were fully confirmed by PTR-TOF-MS. Besides, ring opened by-products, such as acetone, acetic acid, acetaldehyde, etc. were also detected. In this work, the combination of in situ DRIFTS and PTR-TOF-MS provided a promising approach for further understanding of the mechanism of VOCs elimination.
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Xiao Song,Yanan Kong,Xiaoxia Sun,Shuaihu Ma,Siyu Zhu,Zhilou Liu,Hui Liu,Lei Wang,Shu Yang
Achieving efficient catalytic oxidation of VOCs by transition metal oxides at low temperatures is a major challenge. Controlling exposed crystal facets through crystal facet engineering is an efficient strategy for enhancing the catalytic activity of catalysts. Herein, we proposed an anion-inducted method for precisely modulating the exposed crystal facets on Co 3 O 4 catalysts by using different types of cobalt salts. The Co 3 O 4 -a catalyst with highly exposed (220) facets exhibits exceptional catalytic performance, achieving 90% conversion of benzene and toluene at 239 and 240 °C, respectively, which are significantly lower than the temperatures required for Co 3 O 4 -s (286 and 299 °C). The specific reaction rates of Co 3 O 4 -a for benzene and toluene catalytic oxidation were 19.7 × 10 −9 mol/m 2 /s and 15.5 × 10 −9 mol/m 2 /s, which were 3.1 times and 19.4 times than that of Co 3 O 4 -s (6.3 × 10 −9 mol/m 2 /s and 0.8 × 10 −9 mol/m 2 /s), respectively. The excellent activity of Co 3 O 4 -a catalyst was due to stronger interactions between the tetra-coordinated cobalt atoms (Co 4c ) on the (220) crystal plane with reactants by in situ DRIFTS and DFT results. The Co 4c sites act as bifunctional active centers, simultaneously inducing C C bond elongation in aromatic hydrocarbons and O O bond activation in O 2 , which the pre-activation of adsorbed molecules can lower the energy barriers for C H cleavage and ring-opening reactions, and ultimately promotes the deep oxidation of VOCs. This research deepens the understanding of surface structure-oriented catalysis in VOCs oxidation, while aiding the rational design of advanced catalysts.
研究领域:
催化化学
·
环境化学
·
材料科学
·
表面科学
·
物理化学
·
纳米催化
·
能源与环境催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 12
·期 3
·737-749
·
IF 6.119
Zhicheng Xu,Yuran Li,Yuting Lin,Bin Wang,Panting Gao,Tingyu Zhu
The reduction of NO by CO was proposed to be applied for regeneration gas to remove NOx from industrial flue gas with activated carbon purification technology. To improve the activity and sulfur resistance for the reduction of NO by CO in regeneration gas, Cu and Fe modifications on activated carbon were investigated. And various samples were characterized by XRD, XPS, TPD, H2-TPR, in situ DRIFTS and DFT calculations to explain the reaction mechanism and poisoning mechanism. The synergistic effects of oxygen-containing functional groups and metal sites show that –COOH acts as an anchor site for metals and that C–O–C acts as a protective site for Fe3+ under a SO2 atmosphere. Cu2+ sites have a high activity at low temperatures due to the large amount of adsorbed NO and the intermediate NOx− participating in the reaction with the NOx− pathway. Fe3+ sites have a high activity at high temperatures due to the high N–O dissociation activity with the *N pathway and –NCO pathway. DFT calculations proved that the binding Cu2+ and Fe3+ sites have higher activity than free Cu2+ and Fe3+ sites. A high content of SO2 exhibits various poisoning effects, mainly including the sulfation of metal sites, deposition of S, and consumption of CO. AC-Fe-H exhibits excellent resistance and stability against SO2 and H2O due to less S deposition caused by consumption through the S–CO reaction, slight sulfation caused by the protective effect of Fe2+ and C–O–C on Fe3+ sites and better hydrophobicity.
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2025
·
IF 3.7
Wei Liu,Xiaoshen Li,Shaohui Xiong,Xueyang Jiang,Jiayan Yan,Xiang Duan,Yingtian Zhang,Qingpeng Cheng,Ye Tian,Xingang Li
CO 2 hydrogenation to methanol is a critical technology for hydrogen energy conversion and a promising approach to mitigate the energy crisis and greenhouse effect. However, developing highly selective catalysts remains a major challenge for its practical application. Herein, we synthesize an efficient CoCuInO-r catalyst with Cu 11 In 9 and Co 0 dual sites on In 2 O 3 via a sol-gel method. The Cu 11 In 9 intermetallic compound enhances H 2 adsorption capacity and strength, and increases oxygen vacancy concentration on the catalyst surface, thereby improving CO 2 activation and hydrogenation efficiency. Meanwhile, Co 0 suppresses the desorption of the *CO species, facilitating its further hydrogenation to methanol. In-situ DRIFTS experiments indicate that the CO 2 hydrogenation to methanol over CoCuInO-r follows the formate pathway. Compared with CuInO-r (containing Cu 11 In 9 on In 2 O 3 ), CoCuInO-r exhibits a ∼20% increase in methanol selectivity and a 2-fold higher methanol space-time yield, reaching 7.68 mmol·g cat -1 ·h -1 at 300 °C and 4 MPa.
研究领域:
催化
·
能量转换
·
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Qiuxia Liu,Meicheng Wen,Yunlong Guo,Shengnan Song,Guiying Li,Taicheng An
Cyclohexane, a typical volatile organic compound (VOC), poses high risks to the environment and humans. Herein, synthesized PdAg/Fe2O3 catalysts exhibited exceptional catalytic performance for cyclohexane combustion at lower temperatures (50% mineralization temperature (T50) of 199 °C, 90% mineralization temperature (T90) of 315 °C) than Pd/Fe2O3 (T50 of 262 °C, T90 of 335 °C) and Fe2O3 (T50 of 305 °C, T90 of 360 °C). In addition, PdAg/Fe2O3 displayed enhanced stability by alloying Ag with Pd. The redox and acidity of the PdAg/Fe2O3 were studied by XPS, H2-TPR, and NH3-TPD. In situ diffuse reflectance infrared Fourier transform spectroscopy and proton-transfer-reaction time-of-flight mass spectrometry were applied to identify the intermediates formed on the catalyst surface and in the tail gas during oxidation, respectively. Results suggested that loading PdAg onto Fe2O3 significantly enhanced the adsorption and activation of oxygen and cyclohexane, oxidative dehydrogenation of cyclohexane to benzene, and catalytic cracking of cyclohexane to olefins at low temperatures. This in-depth study will benefit the design and application of efficient catalysts for the effective combustion of VOCs at low temperatures.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano Research
·
2023
·Vol. 17
·期 1
·297-306
·
IF 9.9
Xie Jing,Lu Zhenjiang,Feng Yue,Huang Jianguo,Hu Jindou,Hao Aize,Cao Yali
Defect modulation currently plays a decisive role in addressing the poor photoabsorption, sluggish electron hole separation, and high CO 2 activation barrier in photocatalytic CO 2 reduction. However, hunting for a straightforward strategy to balance the concentration of oxygen vacancy and metal cation defect in one photocatalyst is still a great challenge. Herein, a bismuth vacancies BiOBr nanosheets (BiOBr-1) on the exposed [001] facets were constructed via an acetic acid molecule modification strategy, which can repair oxygen defect by bismuth vacancy in low-temperature solid-state chemical method. Benefiting from the formed bismuth defects that can not only broaden light absorption and elevate charge separation efficiency, but also enhance adsorption and activation of CO 2 molecules, the evolution rates of photocatalytic CO 2 conversion into CO (71.23 µmol·g −1 ·h −1 ) and CH 4 (8.90 µmol·g −1 ·h −1 ) attained by BiOBr-1 are superior 7.1 and 11 times to that of plate-like BiOBr. The photocatalytic mechanisms including adsorption concentration and activation process of CO 2 are further revealed by the in situ diffuse reflectance infrared flourier transform spectra (DRIFTS). This finding of the existence of distinct defects in ultrathin nanosheets undoubtedly leads to new possibilities for photocatalyst design using two-dimensional materials with high solar-driven photocatalytic activity.
研究领域:
材料科学
·
环境科学
·
纳米技术
·
催化
·
物理化学
✓ 已验证
DOI
高影响因子
Catalysts
·
2025
·Vol. 15
·期 6
·538
·
IF 4
Jinlong Wen,Ziying Hu,Hongpeng Jia,Jing Chen,Can-Zhong Lu
The construction of multicomponent transition metal oxide catalysts can effectively increase the surface defects of catalysts, and bring a synergistic effect from different components, thus enhancing the generation of reactive oxygen species and improving the catalytic activity of catalysts for volatile organic compounds (VOCs) oxidation. In this article, CuO/Co3O4catalysts with abundant oxygen vacancies for the degradation of ethyl acetate was prepared by a simple impregnation method. The effect of the ratio of Co/Cu on the redox capacity, oxygen vacancy, active oxygen species and catalytic oxidation activity of ethyl acetate were studied. The 90% conversion and mineralization temperatures of ethyl acetate for the optimal catalyst Co3O4-20Cu are 211 and 214 °C (WHSV = 60,000 mL/(g·h), 1000 ppm ethyl acetate), which also shows good stability and excellent water vapor resistance. Compared with pure Co3O4, the CuO/Co3O4catalysts have more oxygen vacancies, provide more reactive oxygen species, allowing the catalyst better low-temperature reduction. Through in situ DRIFTS study, the intermediates of ethyl acetate decomposition were analyzed, then a possible catalytic oxidation mechanism of ethyl acetate on the Co3O4-20Cu catalyst was proposed. In addition, we prepared a Co3O4-20Cu/cordierite monolithic catalyst on the basis of Co3O4-20Cu, exhibiting a good catalytic activity in degradation of ethyl acetate.
研究领域:
催化化学
·
环境科学
·
材料化学
·
化学工程
·
表面化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）