Journal of CO2 Utilization
·
2018
·
IF 5.503
Xue-Dong Li,Yu Cao,Ran Ma,Liang-Nian He
Efficient CuI/1,10-phen-catalyzed three-component cascade reaction of propargylic alcohols, CO 2 , and 2-aminoethanols has been firstly developed for the thermodynamically favourable preparation of 2-oxazolidinones. In the presence of commercially available CuI, 1,10-phen (1,10-phenanthroline) and t -BuOK, the cascade reaction afforded the desired products in good to excellent yields with a broad substrate scope (14 examples). The predicted copper complex Cu 2 I 2 (phen) 2 in situ formed from CuI and 1,10-phen could activate the triple bond through coordination. The isolation of α-alkylidene cyclic carbonate as the reaction intermediate suggests that the carboxylative cyclization of propargylic alcohol with CO 2 , followed by ring-opening reaction, is involved in the one-pot three-component cascade reaction.
研究领域:
有机化学
·
催化
·
二氧化碳利用
·
合成方法学
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2021
·
IF 9.811
Zeyu Jin,Juan Lyu,Yi-Lu Zhao,Huanglong Li,Zuhuang Chen,Xi Lin,Guoqiang Xie,Xingjun Liu,Ji-Jung Kai,Hua-Jun Qiu
Designing and fabricating bifunctional electrocatalysts for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is crucial to high-performance rechargeable metal–air batteries. Herein, we introduce a generic dealloying procedure to fabricate nanoporous spinel high-entropy oxides (HEO) (AlCoFeMoCr)3O4 as the OER catalysts, incorporated with highly dispersed Pt or PtPdCuAgAu clusters/nanoparticles of ∼1.5 nm in diameters as the ORR catalysts on the porous HEO. Our combined experimental results and first-principles density functional theory (DFT) calculations clearly indicate that the ORR activity of Pt clusters can be enhanced and stabilized through strong interactions with the HEO substrates, and at the same time, the presence of Pt can boost the OER performance of the HEO. In particular, the nanoporous AlCoFeMoCr/Pt composite exhibits a comparable OER activity as the best reported data, while its ORR activity exceeds the performance of commercial Pt/C in alkaline solutions. We expect such multicomponent HEO/metal composite systems would provide a new combinatorial materials design path to ensure multiple catalytic functionalities.
研究领域:
材料科学
·
电化学
·
催化
·
能量存储与转换
·
纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Yanling Qiu,Xinyue Zhang,Hui Han,Zhiqiang Liu,Jingquan Liu,Xuqiang Ji
Controllably constructing the functional microscopic surfaces, especially via the escape of metal atoms from extremely stable texture to achieve super-hydrophilic interfaces, as efficient bifunctional catalysts for water splitting is a daunting challenge but critical for sustainable economic development. Based on hydrothermal coordination strategy, we take advantage of strong oxidizing property of nitrate ions to realize temperature-controllable atom-escape of metal Ni for self-assembling super-hydrophilic hydroxide FeNi–OH on nickel base as electrocatalysts of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Such distinctive Ni source, resulting in improved ohmic contact and mechanical robustness of catalysts, in conjunction with super-hydrophilicity-accelerated bubble separation and electrolyte contact, endows the catalyst with excellent electrocatalytical activity for both HER and OER in alkaline solution. Super-hydrophilic FeNi–OH delivers the current density of 50 mA cm −2 at overpotentials of 236 mV for OER and 196 mV for HER. Water electrolysis with FeNi–OH as anode and cathode demands a cell voltage of 1.664 V to drive 50 mA cm −2 in 1.0 M KOH, continuously operating for 25 h. This study opens up an avenue in establishing super-hydrophilic structure via self-assembly of the escaped atoms, broadening the horizon on low-cost iron-containing catalyst preparation for energy conversions.
研究领域:
电化学
·
能量转换
·
材料科学
·
催化
·
可再生能源
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 19
·7075-7081
·
IF 0
Hui Liu,Jun Yang
Bimetallic heterodimers often exhibit unique and superior properties different from each of the constituent materials due to the synergistic effect between the two component metals. Herein, we present the synthesis of bimetallic heterodimers consisting of Ag and hollow structured Pt nanoparticles (Ag–hPt) through a structural transformation at elevated temperature. In this strategy, core–shell Ag–Pt nanoparticles are first prepared and, subsequently, converted into bimetallic Ag–hPt heterodimers via the inside-out migration of Ag in core–shell Ag–Pt nanoparticles. The heat treatment at elevated temperature is employed to promote the inside-out diffusion of Ag from the core region of the core–shell nanoparticles. The resulting bimetallic Ag–hPt heterodimers display significantly different optical and catalytic properties from their core–shell Ag–Pt nanoparticle precursors. The synthetic technique and mechanistic understanding may provide new opportunities to design and fabricate heterogeneous nanostructures with interesting physicochemical properties.
研究领域:
纳米材料
·
催化
·
物理化学
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材料科学
✓ 已验证
DOI
APPLIED ORGANOMETALLIC CHEMISTRY
·
2018
·Vol. 32
·期 12
·e4572
·
IF 3.581
Xiaoming Tao,Yunhai Wu,Yunying Wu,Bing Zhang,Haitao Sha,Ligen Cha,Ningning Liu
Activated carbon-supported cobalt molybdate (CoMoO 4 /AC) composite was conveniently fabricated using a simple hydrothermal route and high-temperature calcination, aiming to create a novel heterogeneous catalyst for activation of peroxymonosulfate (PMS) to degrade organic dyes. The CoMoO 4 /AC catalyst was characterized using scanning electron microscopy, powder X-ray diffraction, energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, elemental mapping analysis and X-ray photoelectron spectroscopy. Efficient catalytic activity, high stability and superior reusability were observed. Additionally, the catalytic performance of CoMoO 4 /AC was systematically assessed through numerous controlled experiments and several operational factors, such as catalyst dosage, oxidant dosage, reaction temperature, initial pH and catalyst stability. Under the condition of CoMoO 4 /AC = 0.1 g l −1 , oxidant = 2.0 mM, dye = 100 mg l −1 , T = 25°C, the removal of methylene blue reached 90% within 60 min without pH adjustment. Batch experiment results showed that the degradation of organic dye relied upon the dosage of catalyst and oxidant and reaction temperature. Further, high catalyst and oxidant dosage, as well as high reaction temperature, were favorable for dye removal. Moreover, quenching experiments suggested that the CoMoO 4 /AC catalyst successfully activated PMS to generate sulfate and hydroxyl radicals. A rational mechanism is proposed based on a non-radical process and a free radical process. The result revealed that the enhanced active sites were mainly ascribed to the synergistic effects between Co species and oxygen-containing functional groups (especially ketone groups) on the catalyst surface. The findings of this study demonstrated the as-prepared CoMoO 4 /AC composite has potential superiority for refractory organic contaminant removal from water.
研究领域:
环境科学
·
材料化学
·
化学工程
·
水处理技术
·
催化
✓ 已验证
DOI
高影响因子
WATER ENVIRONMENT RESEARCH
·
2019
·Vol. 91
·期 7
·650-660
·
IF 1.24
Shengkai Xu,Huaqi Bi,Guangqing Liu,Bensheng Su
Advanced and optimized textile wastewater treatment by catalytic ozonation and activated carbon (AC) adsorption was investigated. Scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy indicated that Mn and Ce oxides were successfully loaded on the γ-Al 2 O 3 support, and MnO 2 , Mn 2 O 3 , CeO 2 , and Ce 2 O 3 were the main components of the catalyst. Actual textile wastewater from biochemical effluent was used as experiment wastewater. The removal efficiencies of chemical oxygen demand (COD) and chromaticity were approximately 30.6% (414–287 mg/L on average) and 99.3% (4,033 times to 27 times on average), respectively during the 30-day on-site continuous-flow test with an ozone dosage, contact time, and gas–liquid ratio of 100 mg/L, 15.7 min, and 2.9, respectively. Following 1 g/L AC adsorption, the effluent COD concentration was reduced to 40 mg/L. By contrast, AC adsorption without catalytic ozonation as pretreatment required 10 g/L AC dosage to achieve similar treatment results. Gas chromatography–mass spectrometry analyses indicated that volatile phenols, sulfides, and aniline in wastewater were completely removed after treatment. Inductively coupled plasma results further showed that the active components of MnO x –CeO x in the catalyst were stable after continuous use for 60 days. Practitioner points Mesoporous catalyst synthesized by impregnating MnO x –CeO x on γ-Al 2 O 3 support. Catalytic ozonation and AC adsorption were combined to degrade organics. Maximum degradation of COD and chromaticity by optimizing process variables. The efficiency of the method was compared to that of single AC adsorption. Graphical In this process, textile wastewater and ozone are introduced into the reactor. The effluent discharged from catalytic ozonation reactor is pumped into activated carbon adsorption reactor to further remove organic pollutants in water.
研究领域:
环境工程
·
水处理技术
·
催化
·
污染控制
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2019
·
IF 7.149
Bojing Sun,Wenjie Ma,Na Wang,Ping Xu,Leijiang Zhang,Bianna Wang,Honghong Zhao,Kun-Yi Andrew Lin,Yunchen Du
Metal-free heterogeneous catalysts are receiving more and more attention for wastewater remediation by activating peroxymonosulfate (PMS) due to their environmental benign. However, carbon-based materials as the most typical metal-free heterogeneous always suffer from poor durability. Inspired by the fact that a conjugated system may facilitate the electron transfer during PMS activation, we innovatively select polyaniline (PANI) as a new PMS activator and investigate its catalytic performance in detail. It is found that PANI can display better catalytic performance than traditional metal-based catalysts and popular N-doped carbocatalysts in methyl orange (MO) degradation. More importantly, PANI is not only universal for various pollutants degradation but also maintains its catalytic performance in repeated degradation experiments. The stable N sites in the conjugated chains and the oxidation-resistance benzene rings as the building units are considered to be responsible for such an excellent durability. In addition, the influences of some routine factors and actual water backgrounds are comprehensively checked and analyzed. The quenching experiments and electron paramagnetic resonance confirm that MO degradation is achieved through both radical and nonradical pathways, where SO4•– and 1O2 are primary reactive species. The reaction mechanism is also proposed with the assistance of X-ray photoelectron spectroscopy.
研究领域:
环境化学
·
材料科学
·
催化
·
水处理
·
污染物降解
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2014
·
IF 8.535
Jia Zhang,Junjie Li,Zhenlong Wang,Xiaona Wang,Wei Feng,Wei Zheng,Wenwu Cao,PingAn Hu
Large-area heteroatom-doped graphene films are greatly attractive materials for various applications, such as electronics, fuel cells, and supercapacitors. Currently, these graphene films are prepared by the high-temperature chemical vapor deposition method, which produces a low doping level in N-doped graphene (NG) and fails in the synthesis of large-area S-doped graphene (SG) film. Here, we report a low-temperature method toward the synthesis of large-area heavily heteroatom-doped graphene on copper foils via a free radical reaction using polyhalogenated aromatic compounds. This low-temperature method allows the synthesis of single-layer NG film with a high nitrogen content, and the production of large-area SG film for the first time. Both doped graphenes show enhanced electrical properties in field effect transistors as well as high-performance electrocatalysts for fuel cells.
研究领域:
材料科学
·
纳米技术
·
能源存储与转换
·
电子学
·
催化
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2018
·
IF 6.434
Xiaolong Liu,Li Chen,Tingyu Zhu,Ruliang Ning
Catalytic oxidation of chlorobenzene over noble metal catalysts Pd/TiO 2 , Pt/TiO 2 , Ru/TiO 2 , and Rh/TiO 2 was evaluated, and Ru/TiO 2 contributed the highest catalytic activity and CO 2 selectivity. During the oxidation, polychlorinated benzenes PhCl x (x ≥ 2) were observed, and Ru/TiO 2 showed apparently lower PhCl x concentrations than other three samples. With the improvement of temperature, the maximum concentration appeared in the sequence of dichlorobenzene (PhCl 2 ), trichlorobenzene (PhCl 3 ), tetrachlorobenzene (PhCl 4 ), and pentchlorobenzene (PhCl 5 ), whereas the concentration of hexachlorobenzene (PhCl 6 ) was always low and showed no apparent regularity. Besides, the dioxin-like PCBs (dl-PCBs) were collected and analyzed for Pd/TiO 2 and Ru/TiO 2 . The ∑dl-PCBs produced by Pd/TiO 2 (0.0055 ng WHO-TEQ/Nm 3 ) was about 1.5 times that of Ru/TiO 2 (0.0027 ng WHO-TEQ/Nm 3 ). XPS analyses revealed that Ru/TiO 2 -used and Rh/TiO 2 -used gave the lowest and the highest Cl content of 0.61% and 1.87%. Ru/TiO 2 -used afforded the lowest (Cl ad +Cl or )/Cl value (22.1%) and the highest Cl br /Cl value (77.9%), which might be an important reason for its strongest chlorine removal ability and the lowest yields of polychlorinated by-products, whereas other three catalysts showed similarity in the Cl distributions. Additionally, systematic in-situ FTIR studies were conducted, and a reaction mechanism for the catalytic oxidation of chlorobenzene was proposed.
研究领域:
环境化学
·
催化
·
污染控制
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2013
·Vol. 2
·期 4
·1150-1158
·
IF 0
Bin Hua,Meng Li,Bo Chi,Li Jian
Two types of anode were prepared for a comparative study of their electrochemical performance and carbon deposition resistance. The first one was the Ni–YSZ cermet anode; and the other, designated as the Ni–MnO/Ni–YSZ, was the Ni–YSZ anode plus an on-cell reforming layer of Ni–MnO in situ reduced from MnNi2O4 with a microstructure of fine Ni particles embedded in MnO matrix. With the Ni–MnO layer on the top surface, open circuit polarization resistance of the Ni–YSZ anode decreased approximately by 1/2 in H2-3 mol% H2O and by more than 1/3 in CH4-3 mol% H2O at temperatures ranging from 650 to 800 °C. Carbon fibers were observed in the Ni–YSZ anode, rather than in the Ni–MnO/Ni–YSZ anode, after initial impedance measurements in CH4-3 mol% H2O for 1 h. The polarization resistance of both anodes at 800 °C increased with time up to 6 h in CH4-3 mol% H2O due to carbon deposition; however, the carbon formed in the Ni–MnO/Ni–YSZ anode had a lower degree of graphitization. In the atmosphere of CH4-20 mol% H2O, carbon deposition was completely depressed in the Ni–MnO/Ni–YSZ anode at 800 °C and 200 mA cm−2, which ensured a higher and more stable electrochemical performance than that of the Ni–YSZ anode.
研究领域:
材料科学
·
电化学
·
能源工程
·
催化
✓ 已验证
DOI
CHEMICAL ENGINEERING JOURNAL
·
2013
·
IF 3.473
Bo Yang,Yunfei Zhang,Shubo Deng,Gang Yu,Yonghong Lu,Jinhua Wu,Jianzhong Xiao,Gang Chen,Xiaobing Cheng,Lili Shi
The Pd/Al nanoparticles (NPs) prepared by aqueous cementation were employed to probe hydrodechlorination (HDC) efficiencies of 4-chlorophenol (4-CP) in aqueous solution and 2-chlorobiphenyl (2-PCB) in surfactant solution. Major factors affecting HDC performance were investigated including acidic types, pH conditions, and surfactant types and their concentrations. Among HCl, H 2 SO 4 , H 3 PO 4 , formic acid, and acetic acid, only HCl was the proper pH adjustor to initiate HDC reaction of 4-CP with Pd/Al NPs at pH 3.0 due to the particular penetration function of active Cl − on the compact oxide film of Al. Aqueous pH states obviously influenced HDC efficiency and its values stable at pH 3–4 were the optimum range for HDC with HCl adjustor. 0.389 mM of 4-CP could be almost completely dechlorinated into phenol after 30-min reaction using 2 g/L of Pd/Al NPs with 1.2 wt.% of Pd loading. In addition, the effect of surfactants on HDC process of highly hydrophobic 2-PCB was explored, which were employed for its better solubilization. The addition of surfactants including SDS, CTAB, Tween 80, or Brij 30 had adverse effect on HDC activity of Pd/Al NPs due to their inhibiting effect on Al corrosion. The adverse effect was closely related with the concentrations of surfactants especially for each CMC level and molecular structures.
研究领域:
环境化学
·
纳米修复
·
水处理
·
催化
·
污染物降解
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2021
·
IF 4.126
Yifan Li,Le Lin,Lijun Gao,Rentao Mu,Qiang Fu,Xinhe Bao
Oxygen vacancies (Vos) play a vital role in the physical and chemical properties of oxide materials and their applications. Because Vos are first produced on oxide surfaces, it has been often recognized that they are richer at the top surface than at the subsurface or bulk region. Here the depth distribution of Vos in reduced manganese oxide (MnOx) films has been studied by a combination of ion-sputtering treatment and variable-angle X-ray photoelectron spectroscopy measurement. The density of Vos on the top surface is determined to be ∼8% lower than that in the subsurface region after reduction treatment of the oxide in CO at 573 K. Density functional theory calculations show that lattice oxygen atoms in the bulk tend to migrate and fill into the Vos on the top surface with a barrier of 0.94 eV at most. The stability of Vos in the bulk is higher than that on the surface via a reduced Mn3O4 skeleton, which can be reflected by the energy of oxygen filling at the Vo.
研究领域:
材料科学
·
表面化学
·
催化
·
固态物理
·
计算材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）