INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·Vol. 43
·期 14
·7038-7045
·
IF 4.229
Rui Lu,Min Hu,Caili Xu,Yi Wang,Yun Zhang,Bin Xu,Daojiang Gao,Jian Bi,Guangyin Fan
Developing effective catalysts for hydrogen evolution from hydrolysis of ammonia borane (AB) is of great significance considering the useful applications of hydrogen. Herein, graphitic carbon nitride (g-C 3 N 4 ) prepared through the simply pyrolysis of urea was employed as a support for Rh nanoparticles (NPs) stabilization. The in-situ generated Rh NPs supported on g-C 3 N 4 with an average size of 3.1 nm were investigated as catalysts for hydrogen generation from the hydrolysis of AB under mild conditions. The Rh/g-C 3 N 4 catalyst exhibits a high turnover frequency of 969 mol H 2 · (min·mol Rh ) −1 and a low activation energy of 24.2 kJ/mol. The results of the kinetic studies show that the catalytic hydrolysis of AB over the Rh/g-C 3 N 4 catalyst is a zero-order reaction with the AB concentration and a first-order reaction with the Rh concentration. This work demonstrates that g-C 3 N 4 is a useful support to design and synthesis of effective Rh-based catalyst for hydrogen-based applications.
研究领域:
催化化学
·
能源材料
·
纳米催化
·
氢能源
·
反应动力学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 31
·19968-19978
·
IF 10.7
Zicheng Huang,Wenjie Shao,Yijuan Zheng,Junyu Wang,Mao Wang,Shuang Li,Xiaohui Xu,Chong Cheng,Changsheng Zhao
Transition metal oxide-based catalysts are known as the most active oxygen evolution reaction (OER) catalysts due to their intrinsic electronic structures and binding strength of oxygenated intermediates. However, even the most active transition metal oxide-based OER catalysts have a turnover frequency far lower than that of the oxygen-evolving complexes in biological systems for intermolecular site aggregation. Herein, we implement the hybridization of a metal–organic framework and tungstic acid (WO3·xH2O-in-MIL-88) to achieve ordered FeNi site isolation at the molecular level and avoid intermolecular decomposition during the catalysis process. The optimized hybrid with 15% tungstic acid (15%-WO3·xH2O-in-MIL-88) achieves a much-enhanced OER activity and stability in terms of a low overpotential of 263 mV to reach a current density of 10 mA cm−2, a low Tafel slope of 39 mV dec−1, and long-term stability, which is much superior to that of the commercial RuO2 catalyst.
研究领域:
材料化学
·
电化学
·
催化化学
·
能源科学
·
无机化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 79
·75359-75364
·
IF 3.289
Chunmei Li,Furen Zhang
A series of pyrrolo[2,3,4-kl]acridin-1-one derivatives were successfully synthesized from facile materials (enaminone and isatin) using a reusable solid acid as catalyst in water. A variety of structurally diverse enaminones and various isatins bearing different functional groups tolerated the reaction and gave the corresponding goal products with good to excellent yields. Advantages of this strategy include the mild conditions, operational simplicity, being convenient and environmentally benign, and the reusability of the heterogeneous catalyst. A mechanism was proposed to explain the formation of different substituted pyrrolo[2,3,4-kl]acridin-1-one derivatives.
研究领域:
有机化学
·
药物化学
·
绿色化学
·
杂环合成
·
催化化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 87
·70743-70748
·
IF 3.84
Zhiwei Liu,Ping Li,Fuqiang Zhai,Qi Wan,Alex A. Volinsky,Xuanhui Qu
Nanostructured tungsten carbide with high surface area and containing amorphous carbon is prepared by a low temperature combustion synthesis method. The nanostructured tungsten carbide is used as the catalyst in a gas diffusion electrode. The obtained WC with different carbon content was investigated by XRD, FESEM, TG-DTA, BET and XPS. When the molar ratio of C/W is 19/3, the WC particles with different carbon content are obtained after a carbonizing process between 900 and 1400 °C, and the content of free carbon in WC also increases gradually with temperature. The carbon content is tested by the high frequency combustion-infrared absorption method in a carbon sulfur analyzer. The electrochemical properties of the tungsten carbide for the oxygen reduction reaction are characterized by its polarization curves and electrochemical impedance. The results show that the presence of the appropriate amorphous carbon is beneficial for improving the conductivity and dispersibility of the tungsten carbide catalyst, and more active centers can be provided by the catalyst.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源材料
·
表面科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 110
·108791-108800
·
IF 3.289
Wei Zhou,Haiqian Zhao,Jihui Gao,Xiaoxiao Meng,Shaohua Wu,Yukun Qin
The Fenton system (Fe2+/H2O2) generates ·OH with a high oxidation potential. However, as reactants themselves, H2O2 and Fe2+ can act as ·OH initiators as well as ·OH scavengers, leading to the need for a high dosage of reactants and increased costs. As a mixing-sensitive reaction, the ·OH-related reaction kinetics (·OH with Fe2+, H2O2, and RhB) was determined from the reaction rates (which were a constant in this work) and stoichiometry, in which the latter could be regulated by an addition strategy of Fenton reagents. This suggests that ·OH competitive reactions could be controlled by applying a macrolevel addition strategy. Herein, the effects of different addition approaches of Fe2+ and H2O2 on ·OH competitive reactions were quantitatively and systematically studied by analyzing the removal of the model pollutant RhB. We found that without stirring, and compared with a one-time addition, once H2O2 or Fe2+ was added in a step-wise pattern (e.g., one drop by one drop, 2 times, or 4 times), a high concentration of H2O2 or Fe2+ existed in a localized place for a longer period, resulting in a lower proportion of ·OH reacting with RhB, which we ascribed to an enhanced reaction between Fe2+, H2O2, and ·OH. However, when H2O2 and Fe2+ were added from two close points without stirring, a larger proportion of ·OH was scavenged by H2O2 and Fe2+; while under stirring, even a one-time addition of H2O2 or Fe2+ could cause severe scavenging of ·OH. The results also revealed a linear relationship between the RhB removal percentage and wavelength blue-shifts. This study showed that microlevel ·OH competitive reactions could be controlled by applying a macrolevel addition strategy of Fenton reagents without the addition of external chemicals. The results suggest this methodology can also offer an approach to lower ·OH invalid consumption by regulating the addition strategy in bigger reactors.
研究领域:
环境化学
·
水处理技术
·
高级氧化过程
·
反应动力学
·
污染控制化学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 18
·8566-8577
·
IF 3.3
Tingting Tang,Bo Jin,Ping Zhao
Aromatic nitro compounds are the main components of explosives. They are not only explosive and dangerous but also have high toxicity and high stability in the human body, soil, and water resources, destroying the ecological environment. Herein, a simple hydrothermal method is used to successfully prepare layered MIL-100 (Fe). A series of aromatic nitro compounds including p-nitrophenol (PNP), nitrobenzene (NB), dinitrotoluene (2,4-DNT), dinitrophenol (2,4-DNP), and 2,4,6-trinitrophenol (2,4,6-TNP) were degraded by the photo-Fenton method. The MIL-100 (Fe) photo-Fenton agent can almost completely degrade PNP within 2 min. Similarly, it has a good degradation effect on other pollutants. Finally, the mechanism of the photo-Fenton reaction was discussed by product analysis and free radical capture experiments after the photochemical reaction. This study demonstrates the potential application value of MIL-100 (Fe) as a photo-Fenton reagent to degrade nitroaromatic explosives.
研究领域:
环境化学
·
材料科学
·
催化化学
·
环境污染与控制
·
应用化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 27
·14278-14285
·
IF 8.867
Haibo Tang,Xinlong Tian,Junming Luo,Jianhuang Zeng,Yingwei Li,Huiyu Song,Shijun Liao
Transition metal nitrides have recently attracted significant interest as electrocatalysts for the oxygen reduction reaction (ORR) owing to their low electrical resistance and good corrosion resistance. In this paper, we describe the preparation of a Nb-based binary nitride material with a porous nanogrid morphology/structure. The catalyst exhibited good catalytic activity and high stability towards oxygen reduction. We also intensively investigated the effect that doping with a second transition metal had on the performance of the catalyst. We found that the ORR activity of NbN could be enhanced significantly by enriching the d electrons of Nb through doping with a second transition metal, and that doping with cobalt resulted in the best improvement. Our optimal catalyst, Nb0.95Co0.05N, had an ORR activity ∼4.6 times that of NbN (current density @ 0.6 V vs. the RHE). XPS results revealed that Co doping increased the proportion of Nb in a low-valence state, which may be one of the most important reasons for the enhanced performance. Another important reason is the high surface area resulting from the porous nanogrid morphology. As transition metal doping is an attractive way to enhance the activity of nitride catalysts, our work may provide an effective pathway to achieve this.
研究领域:
材料科学
·
电化学
·
纳米科技
·
催化化学
·
能源材料
✓ 已验证
DOI
高影响因子
SOLID STATE IONICS
·
2018
·
IF 2.751
Xue Bai,Wen Li,Aijia Wei,Qian Chang,Lihui Zhang,Zhenfa Liu
Spinel Li 4 Ti 5 O 12 doped with F was synthesized via the solid-state reaction of anatase TiO 2 , Li 2 CO 3 , and NH 4 F. The structural characterization and electrochemical performance evaluation of the prepared materials were carried out utilizing X-ray diffraction, scanning electron microscopy, galvanostatic charge-discharge, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) tests. The lattice parameters of all samples were calculated using an internal standard and Rietveld refinement method. The results indicate that the F was successfully doped into the lattice structure of Li 4 Ti 5 O 12 , and this process did not influence the crystal structure and superficial morphology. Moreover, the best-performing material, Li 4 Ti 5 O 11.9 F 0.1 delivers superior rate capacities of 165, 162.1, 160.0, 142.3, 125.1, and 99.2 mAh g −1 , at 0.2 C, 0.5 C, 1 C, 3 C, 5 C, and 10 C, respectively, which is higher than those of Li 4 Ti 5 O 12 (150.0, 135.0, 123.5, 93.7, 76.4, and 56.8 mAh g −1 at the same C-rates), and the cycling retention is 82.7% after 150 cycles at 5 C. Meanwhile, the charge-transfer resistance (R ct ) of Li 4 Ti 5 O 11.9 F 0.1 (56.4 Ω) is lower than that of pure Li 4 Ti 5 O 12 (80.6 Ω), and the lithium-ion diffusion coefficients (D Li + ) of Li 4 Ti 5 O 11.9 F 0.1 (2.505 × 10 −10 cm 2 s −1 ) is higher than that of pure Li 4 Ti 5 O 12 (1.694 × 10 −10 cm 2 s −1 ).
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固体化学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2017
·
IF 2.299
Yuan-Zi Xu,Cheng-Zong Yuan,Xue-Ping Chen
To design highly efficient and low-cost electrocatalysts for oxygen evolution reaction (OER) is a great challenge for electrochemical water splitting. Here we introduce a simple and cost-effective strategy for one-step synthesis of a three-dimensional Ni 3 S 2 /MoS X (x is close to 3) nanosheets on Ni foam (NF) via a sovelthermal reaction. The electrochemical performance of the Ni 3 S 2 /MoS X nanosheets on NF has been investigated and exhibits superior OER electrocatalytic activity as well as excellent electrochemical durability. As a novel non-noble-metal OER catalyst operating in basic electrolytes, this 3D cathode exhibits an onset overpotential of as low as 165 mV, a Tafel slope of 67.5 mV dec −1 and remarkable long-term stability. This catalyst maintains its catalytic activity for at least 14 h and only affords 50, 100, and 150 mA cm −2 OER current densities at overpotentials of 215 mV, 265 mV and 305 mV respectively.
研究领域:
材料科学
·
电化学
·
能源化学
·
纳米科技
·
催化化学
✓ 已验证
DOI
高影响因子
Small
·
2024
·Vol. 20
·期 26
·2310387
·
IF 13
Wei Luo,Yanli Yu,Yucheng Wu,Wenbin Wang,Yimin Jiang,Wei Shen,Rongxing He,Wei Su,Ming Li
Rational design of heterostructure catalysts through phase engineering strategy plays a critical role in heightening the electrocatalytic performance of catalysts. Herein, a novel amorphous/crystalline (a/c) heterostructure (a-CoS/Ni 3 S 2 ) is manufactured by a facile hydrothermal sulfurization method. Strikingly, the interface coupling between amorphous phase (a-CoS) and crystalline phase (Ni 3 S 2 ) in a-CoS/Ni 3 S 2 is much stronger than that between crystalline phase (c-CoS) and crystalline phase (Ni 3 S 2 ) in crystalline/crystalline (c/c) heterostructure (c-CoS/Ni 3 S 2 ) as control sample, which makes the meta-stable amorphous structure more stable. Meanwhile, a-CoS/Ni 3 S 2 has more S vacancies (S v ) than c-CoS/Ni 3 S 2 because of the presence of an amorphous phase. Eventually, for the oxygen evolution reaction (OER), the a-CoS/Ni 3 S 2 exhibits a significantly lower overpotential of 192 mV at 10 mA cm −2 compared to the c-CoS/Ni 3 S 2 (242 mV). An exceptionally low cell voltage of 1.51 V is required to achieve a current density of 50 mA cm −2 for overall water splitting in the assembled cell (a-CoS/Ni 3 S 2 || Pt/C). Theoretical calculations reveal that more charges transfer from a-CoS to Ni 3 S 2 in a-CoS/Ni 3 S 2 than in c-CoS/Ni 3 S 2 , which promotes the enhancement of OER activity. This work will bring into play a fabrication strategy of a/c catalysts and the understanding of the catalytic mechanism of a/c heterostructures.
研究领域:
材料科学
·
电化学
·
催化化学
·
纳米材料
·
能源材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2013
·Vol. 51
·期 8
·1690-1694
·
IF 3.543
Yun-Hai Yu,Xiao-Hui Liu,Di Jia,Bo-Wen Cheng,Yuan-Lin Ren,Fei-Jun Zhang,Hui-Na Li,Peng Chen,Shan Xie
Graphical A universal high reactive ligand, Me 6 TREN, was successfully explored as the reducing agent for the ambient temperature copper-mediated LRP of AN. The key to success is ascribed to the optimized Me 6 TREN amount and reaction conditions employed, producing ideal living free radical polymerization characteristics. The very high chain-end functionality of the resultant polymer has been confirmed by GPC and 1 H NMR analyses as well as the chain-extension reaction.
研究领域:
高分子化学
·
聚合反应
·
功能高分子
·
可控自由基聚合
·
材料化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2013
·
IF 3.473
Manhong Liu,Qiang Bai,Hailian Xiao,Yanyan Liu,Jun Zhao,William W. Yu
Colloidal platinum–ruthenium bimetallic nanoparticles with 2.3 nm were synthesized in solution and then immobilized on tin dioxide powder to make a supported nanocatalyst (Pt–Ru/SnO 2 ). The immobilized bimetallic nanoparticles had the same size and size distribution as the solution dispersed ones. Selective hydrogenation of o -chloronitrobenzene to o -chloroaniline was performed over the as-prepared Pt–Ru/SnO 2 nanocatalyst without using any solvent; 99.5% selectivity to o -chloroaniline at ∼100% conversion was achieved.
研究领域:
催化化学
·
纳米材料
·
有机合成
·
绿色化学
·
应用化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）