JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Jiacheng Xu,Shun Wang,Chenyun Zhang,Jing Zhang,Lihua Xu,Yue Shi,Guoqiang Xu,Shuiliang Yao
Catalyst surface active oxygen species have an important influence on plasma catalytic oxidation . However, the reaction process of CO and O 3 migration and transformation on the catalyst surface during discharge at different temperature is still unclear. In this study, β- and γ -MnO 2 are selected to unveil the roles of different oxygen species under in-plasma catalysis configuration at different temperature in CO oxidation. Operando TPR-DRIFTS-MS is used to reveal CO and O 3 oxidation pathways. The results show that O 3 can react with CO at room temperature, and O 3 is also converted to other reactive oxygen species on the catalyst surface. As the temperature increases, the oxygen species of the catalyst itself (Mn O and Mn-O-Mn) can react with CO to form oxygen vacancies (Mn-□-Mn and Mn=□). Mn-□-Mn are beneficial for O 2 decomposition and promotes the regeneration of Mn O and Mn-O-Mn. The carbonate covered on the surface of the catalyst is the rate-determining step of CO oxidation. It is hoped that Mn-based catalysts with more reactive oxygen species and oxygen defects will be prepared to facilitate low-temperature CO oxidation under plasma conditions.
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
APPLIED SURFACE SCIENCE
·
2020
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IF 6.182
Yudong Zhang,Long Liang,Ziyang Chen,Jinjun Wen,Wen Zhong,Sibei Zou,Mingli Fu,Limin Chen,Daiqi Ye
Self-assembled CeO 2 with 3D hollow nanosphere, nanoparticle and nanocube morphologies were prepared and used to support Cu particles. The obtained samples (denoted as Cu/CeO 2 -hs, Cu/CeO 2 -np and Cu/CeO 2 -nc, respectively) were tested for the reverse water-gas shift (RWGS) reaction. Under the reaction conditions, V (H 2 ): V (CO 2 ) = 3:1 and weight hourly space velocity (WHSV) = 300,000 mL g −1 h −1 , the Cu/CeO 2 -hs sample exhibited the best catalytic performance among the as-prepared catalysts. In order to reveal the key factors affecting the catalytic performance, the physicochemical properties of the catalysts were analyzed by XRD, BET, SEM, TEM, H 2 -TPR, quasi in-situ XPS and in situ UV-Raman techniques. The results point out that the particle size of Cu is not the rate-determining factor while the amount of surface oxygen vacancies is highly correlated with the catalytic reaction rate. In situ UV-Raman and in situ DRIFTS experiments indicate the formation of bidentate carbonate and formate species on oxygen vacancy sites which is thought to be the key intermediates for the RWGS reaction. These findings unravel the crucial roles of surface oxygen vacancies on CO 2 adsorption and activation and also highlight a feasible way for the design of highly efficient catalysts for the important RWGS reaction in chemical industry.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2023
·
IF 7.3
Shuhao Li,Feng Wang,Zongli Xie,Derrick Ng,Boxiong Shen
Zeolitic imidazolate framework-8 (ZIF-8) based catalysts are considered as promising candidates for the selective catalytic reduction of NO by CO (CO-SCR) reaction due to their large specific surface area. However, the structure of ZIF-8 will be damaged during the synthesis procedure of the catalyst, leading to a decrease in their physical properties, which in turn affects the catalytic performance of the catalyst. Herein, a CeO 2 -ZIF-8 core-shell structure was synthesized and doped with Fe, resulting in the formation of Fe@CeO 2 -ZIF-8, for CO-SCR reaction. Characterization results show that the Fe@CeO 2 -ZIF-8 core-shell catalyst has better morphology, thermal stability, and higher specific surface area than the FeCe co-impregnated ZIF-8 catalyst (FeCe@ZIF-8 (IM)). Moreover, the reducibility of the reactive Fe species in the Fe@CeO 2 -ZIF-8 core-shell catalyst is also enhanced. As a result, the Fe@CeO 2 -ZIF-8 core-shell catalyst exhibited higher low-temperature CO-SCR catalytic activity with its NO conversion reaching 99% at 250 °C versus the FeCe@ZIF-8 (IM) catalyst (89% at 250 °C). The experimental results were further verified by density functional theory (DFT) calculations including Electron Localization Function (ELF), Valence Charge Density Difference (VCDD), Projected Density of States (PDOS) and Bader charge analyses. The calculation results revealed that the core-shell configured Fe@CeO 2 -ZIF-8 catalyst has a stronger active metal-support charge transfer and better capacity for the adsorption of the reactants. The reaction mechanism over Fe@CeO 2 -ZIF-8 core-shell catalyst was investigated via in situ DRIFTS experiments, and results showed that the nitro compounds and formate species are critical intermediates in this reaction at a higher temperature range (300–350 °C). This work provides a new strategy for the synthesis of ZIF-8 based catalysts with better properties for CO-SCR reaction.
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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物理化学
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能源化学
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表面科学
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纳米材料
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
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IF 22.1
Jie Tian,Zhijian Wang,Yaqin Hou,Yatao Yang,Haijun Chen,Zhanggen Huang
Inorganic Bi-based halide perovskites have attracted significant attention in the field of CO 2 photoreduction due to their excellent optoelectronic conversion performance and low toxicity. However, the inherent strong localization of electron-hole pairs remains the main factors limiting charge carrier transport and CRR performance. In this work, CBSB-x NCs with different Bi/Sb ratios were synthesized assisted by ultrasound methods to manipulate carrier behavior and assess CRR performance. The photoelectrochemical properties revealed that incorporation of Sb effectively suppressed nonradiative recombination and improved transport efficiency of charge carriers. Among the bimetallic variants, CBSB-1 NCs exhibited enhanced catalytic performance in CO production, with a yield of 38.77 μmol·g −1 and a high selectivity of 96.53 %. In-situ DRIFTS and DFT calculations indicated that Sb as co-catalytic sites promote charge transfer at the Bi-Br-Sb interface, accelerate the rapid evolution of b-CO 3 2- to HCOO - and significantly reduce the reaction energy barrier of CO.
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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纳米技术
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光化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
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IF 13.3
Yaqi Qu,Hualiang An,Xinqiang Zhao,Yanji Wang
High dispersion of active metal is an inevitable requirement to improve the catalytic performance of supported metal catalysts and achieving this goal always requires the support with a large specific surface area. Here we innovatively prepared a ZrO 2 @Pt catalyst using ZrO 2 with a small specific surface area as the core which is coated with highly dispersed Pt nanoclusters (<2 nm). In this process, the surface of ZrO 2 was firstly functionalized to increase the number of hydroxyl group, Pt nanoclusters were formed simultaneously and uniformly coated on the ZrO 2 surface. In this work, much attention was paid to the role of 2-[4-(2-hydroxyethyl)-1-piperazinyl] ethanesulfonic acid (HEPES) and ethanol in the one-pot preparation process. The results showed that HEPES acted as a reductant, while treatment with ethanol promoted both the generation of hydroxyl groups on ZrO 2 surface and the reduction of Pt precursor under mild conditions. As-prepared ZrO 2 @Pt catalyst showed excellent catalytic performance in the selective hydrogenation of nitrobenzene; nitrobenzene was completely converted to aniline with 100 % selectivity at room temperature and 8 bar H 2 pressure within 30 min, and the TOF reached as high as 3304 h −1 . Moreover, ZrO 2 @Pt also exhibited a good reusability and a broad substrate applicability. The results of both DRIFTS analysis and DFT calculation demonstrated that the hydrogenation of nitrobenzene on ZrO 2 @Pt catalyst followed the condensation reaction pathway. Our findings can provide a new approach to obtaining highly dispersed metal nanoparticles on the support with a small specific surface area.
研究领域:
催化
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材料科学
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化学工程
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2024
·
IF 6.5
Qiangqiang Xue,Zhengwen Li,Binhang Yan,Shafqat Ullah,Yujun Wang,Guangsheng Luo
A novel mesoporous SiO 2 encapsulated core-shell NiRh@NiO nanostructure was constructed to enhance the activity and stability of ethanol steam reforming (ESR). At 550 °C and ethanol-WHSV = 21 h −1 , the specific activity and conversion loss (17 h) of NiRh@NiO@m-SiO 2 were 0.42 mol ethanol /(g cat. ·h) and 10.9 %. The alloying of NiRh core, dominated NiO in shell, and abundant mesopore of SiO 2 were confirmed by systematic characterization techniques. The in situ DRIFTS results indicated that alloying Ni and Rh boosted ethoxide dehydrogenation to acetaldehyde and acetate demethanation to carbonate. ReaxFF molecular dynamics (MD) simulations suggested that NiO shell was conducive to water activation, which, in turn, promoted the conversion of CH x O y species. The SiO 2 encapsulation derived confinement effect inhibited both metal core sintering and leaching caused by the filamentous carbon. The abundant mesopores of SiO 2 ensured the facile in-diffusion of water and out-diffusion of carbonaceous products, suppressing carbon deposition within the SiO 2 encapsulation and the destruction of core-shell structure.
研究领域:
催化
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材料科学
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化学工程
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2025
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IF 4.8
Xiao Yang,Heying Zhao,Aiyong Wang,Wangcheng Zhan,Yanglong Guo,Li Wang,Xuan Tang,Yun Guo
SO 2 in the sintering flue gas severely inhibits the CO oxidation performance of commercial Pt/Al 2 O 3 catalysts. However, the major poisoning mechanism of SO 2 on Pt/Al 2 O 3 in CO oxidation in the presence of H 2 O remains to be elucidated. Here, Pt/Al 2 O 3 was pretreated with different reducing atmospheres at high temperatures. Among these, the catalyst pretreated with a CO atmosphere at 600 °C (denoted as Pt/Al 2 O 3 -CO-600) exhibited superior CO oxidation performance and enhanced sulfur resistance in the presence of both H 2 O and SO 2 . The combination of XPS, HAADF-STEM, TG-MS, SO 2 oxidation test, and in-situ DRIFTS reveal that the Pt species on Pt/Al 2 O 3 -CO-600 transformed from Pt oxide clusters to metallic Pt nanoparticles. This transformation enhanced SO 2 adsorption and reactivity, leading to increased sulfate accumulation. Despite the high SO 2 reactivity and sulfate content, in-situ DRIFTS revealed that the CO reaction of Pt/Al 2 O 3 -CO-600 was less hindered by SO 2 and the sulfated Al 2 O 3 . This is attributed to the high ratio of the under-coordinated (UC) Pt sites in Pt/Al 2 O 3 -CO-600, which promotes the reaction intermediates spillover from Pt site to Al 2 O 3 compared to the Pt/Al 2 O 3 . This phenomenon was positively correlated with the sulfur resistance of reduced catalysts. Accordingly, the UC site contributes to the spillover of sulfate intermediate (H 2 SO 4 ), reducing the CO reactivity loss of Pt/Al 2 O 3 due to the intermediate coverage. This study elucidates that the primary poisoning pathway of Pt/Al 2 O 3 in the presence of H 2 O and SO 2 is the difficulty of sulfate intermediate spillover.
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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表面科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Tiping Wei,Liguo Wang,Jiajun Zhang,Yan Cao,Xiang Hui,Jianhui Shi,Shuang Xu,Liyan Zhao,Peng He,Huiquan Li
Bio-based pentamethylene dicarbamate (PDC) belongs to N-substituted carbamates, which are important fine chemicals and organic intermediates. In this work, well-defined CeO2 rods, cubes, and octahedrons were successfully prepared to catalyze the synthesis of PDC by carbonylation of 1,5-pentanediamine (PDA) with methyl carbamate (MC). Among them, CeO2 rods with higher amounts of acid–base sites and abundant oxygen vacancies showed superior intrinsic activity in the PDA carbonylation reaction. In situ FTIR results showed that intermediate polyureas were readily formed in the reaction, and then, CeO2 rods promoted the alcoholysis of polyureas to PDC. In situ DRIFTS results indicated that the surface of CeO2 rods is more favorable for the adsorption and activation of the reactants. CeO2 rods can also be used for the efficient synthesis of a series of N-substituted carbamates. We believe that this work will contribute to the efficient, green, and sustainable production of N-substituted carbamates.
研究领域:
催化
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化学工程
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绿色化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2025
·
IF 13.1
Rui Zhai,Zhenyu Wang,Chang Huang,Chao Zeng,Mengyue Gu,Tianqi Wang,Fanqi Bu,Shaobin Wang,Jinying Zhang
Phosphorus has various crystallographic structures and variable phosphorus-derived structures, which have attracted much attention due to its unique properties. One-dimensional phosphorus structures with atomic substitution in the phosphorus lattice are extremely favored due to their high specific surface area and stable single-atom dispersion. The precise crystal structures and single atomic substitution positions are crucial factors to understand the mechanism of single-atom effects but remain a big challenge. Herein, single crystals composed of 1D zigzag linear phosphorus selenium chains (ZLP-Se) have been produced and characterized by SC-XRD to be P18.56Se1.44 with a space group of Pnma (CSD-2348033). The exact Se substitution positions were further ascertained by calculations of the whole thermodynamic stability phase diagram to have three types of substitution patterns (Se1/P1 mixed occupied positions with intervals of 3Se+2P, 1Se+4P, and 1Se+1P+1Se+2P). The selenium-rich crystal plane (-10-1) has been demonstrated to significantly enhance CO2 adsorption and C−C coupling to obtain ethylene (C2H4). A high photocatalytic CO2 reduction performance (18.0 μmol g−1 h−1, 97.0% electron selectivity for C2H4) has been achieved by the ZLP-Se with the Ag cocatalyst. The adsorption of CO2* and CO* was found to be much stronger on the Se-rich surface of ZLP-Se. The CO* intermediates were found to be energetically favored for protonation and subsequent asymmetrical C−C coupling to produce C2H4, with COCHO* intermediates detected by in situ DRIFTS. The electron was also demonstrated by in situ XPS to transfer from Se and Ag to P under Xe lamp irradiation, confirming the electronic localization effect of ZLP-Se to yield C2H4.
研究领域:
材料科学
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催化
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物理化学
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纳米技术
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
·
2025
·
IF 6.7
Chen Shen,Haiyong Wang,Tianyu Ren,Tianhan Zhu,Tianyu Gao,Mi Luo,Xiaoman Wang,Tong Zhang,Chenguang Wang
The cascade amination of nitrobenzene with benzaldehyde represents an environmentally benign route for imine synthesis in fine chemistry. Nevertheless, challenges including harsh reaction conditions, inefficiency, and poor selectivity hinder its practical implementation. Herein, we report a Pt/Zn x Fe 3-x O y interfacial catalyst system that synergistically modulates both electronic states of Pt nanoparticles (NPs) and acid/base properties of the support to address these limitations. Controlling of chemical composition of Zn x Fe 3-x O y to can efficient regulate electronic state of Pt and acid/base sites of Pt/Zn x Fe 3-x O y . The catalytic performance was strongly dependent on the interfacial electronic interactions and acid-base properties at the Pt/Zn x Fe 3-x O 4 interface. Due to lower work function of ZnFe 2 O 4 , interfacial electrons transfer to Pt from ZnFe 2 O 4 support form rich-electronic Pt accelerated hydrogenation of nitrobenzene. Rich oxygen vacancies and hydroxyl groups as acid and base sites, optimize condensation efficiency and intermediate desorption. This dual regulation strategy achieves exceptional catalytic performance under mild conditions (30 °C, 1 MPa H 2 , 4 h), delivering 96.0 % conversion with 96.25 % imine selectivity. More than 20 different amines compounds and gram-scale of imines (1.495 g) were synthesized over Pt/ZnFe 2 O 4 . In-situ DRIFTS spectroscopy identifies aniline as the critical intermediate, confirming the proposed cascade mechanism. Our work establishes a materials design paradigm leveraging support composition to reconcile electronic and acid-base requirements in tandem catalysis.
研究领域:
催化化学
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材料科学
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化学反应工程
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环境化学
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表面科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2025
·
IF 7.3
Zhouxuan Zang,Jianhua Zhou,Ningke Pang,Wencai Bai,Yong Xiang,Yi Yu,Li Xu,Guoji Liu
High-energy-density sustainable aviation fuels are recognized as effective means to mitigate carbon emissions in the aviation sector. Here, we report various metal-modified layered double hydroxides (LDHs). The screened MgAlSn-LDH catalyst incorporating abundant oxygen vacancies and strong base sites yields (E)-1-(furan-2-yl)-5-methylhex-1-en-3-one (ALD) over 96% at 120 °C for 4 h. The catalyst exhibits promising long-term stability in a fixed-bed reactor at 170 °C. A combination of investigations using in situ DRIFTS studies and DFT calculations reveals that MgAlSn-LDH enhances the adsorption of methyl isobutyl ketone (MIBK) and furfural (FF). Further calculations have shown that the synergy of oxygen vacancies and strong base sites decreases the energy barrier of MIBK enolation, which increases the rate of the enolation reaction. This research provides a versatile synthesis method for improving the alkaline catalytic activity of LDH catalysts, and the performance of the catalysts can be extended to other upgrading processes of biomass chemicals.
研究领域:
催化
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材料科学
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化学工程
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可再生能源
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表面化学
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计算化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2025
·
IF 8.2
Xinyu Chen,Jinhai Leng,Fengying Ma,Jianqing Wu,Yi Jin,Fanglin He,Chao Yang,Haomin Huang,Xuquan Liu,Chongxiong Duan,Shanshan Shang,Daiqi Ye
Direct air capture (DAC) of carbon dioxide (CO2) has emerged as a prominent negative carbon emission technology for mitigating the greenhouse effect. Among various adsorbents, amine-functionalized metal–organic frameworks (MOFs) have shown exciting potential as adsorbents for atmospheric CO2 capture. However, the intrinsic microporosity of many MOFs restricts amine loading and uniform dispersion, diminishing the CO2 adsorption efficiency. In this study, we synthesized a series of hierarchically porous porphyrin-based MOF (HP-PMOF) featuring high-density defects and a combination of micro- and meso- and macropores. The HP-PMOF was subsequently functionalized with short-chain alkyl amines (diethylenetriamine (DETA) and tetraethylenepentamine (TEPA)) and polyamines (polyethylenimine (PEI)) to form HP-PMOF–Amine composites. Evaluations of these adsorbents demonstrated a significantly enhanced CO2 capture performance in DAC applications. Static CO2 adsorption isotherms revealed that HP-PMOF–DETA achieved the highest CO2 uptake of 1.40 mmol g–1, representing increases of 140 and 20 times over unmodified PMOF and HP-PMOF, respectively. Dynamic DAC performance measurements showed that HP-PMOF–DETA maintained 84% regeneration efficiency after ten cycles under 400 ppm of CO2. Breakthrough tests demonstrated enhanced CO2 adsorption capacity across varying relative humidity (0–80%) compared with dry conditions. Mechanistic insights from in situ DRIFTS studies and DFT calculations indicated that, under dry conditions, physisorption and chemisorption synergistically occur between CO2 and amine groups of DETA, forming carbamate or carbamic acid species. Under humid conditions, water facilitated the adsorption of CO2 by promoting the conversion of ammonium carbamate to bicarbonate. This work underscores the significant potential of amine-functionalized hierarchically porous MOFs for advancing the efficacy of DAC technologies.
研究领域:
环境科学
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材料科学
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化学工程
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纳米技术
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物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）