Reaction Chemistry & Engineering
·
2020
·Vol. 5
·期 5
·886-895
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IF 3.441
Xing-Gang Si,Yun-Peng Zhao,Qing-Lu Song,Jing-Pei Cao,Rui-Yu Wang,Xian-Yong Wei
A highly efficient Ni/N–C catalyst was synthesized by facile pyrolysis of a Ni-containing metal–organic framework (Ni-MOF), and its catalytic hydrogenolysis performance towards C–O bonds in lignin was evaluated in detail using diphenyl ether (DPE) as a model compound. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show that the flower-like nanosheets of the Ni-MOF shrink, forming a loose and ordered spherical structure during pyrolysis. Under the optimal conditions, DPE was completely converted and the selectivity to monomers (benzene, cyclohexanol and cyclohexane) reached 99.1%. During the catalytic hydrogenolysis conversion (CHC) of DPE, the direct cleavage of the Caromatic–O bond affording benzene and phenol is the major reaction pathway, and a low H2 pressure is crucial to increase the monomer selectivity. Furthermore, Ni/N–C-450 shows high hydrogenolysis activity for other lignin-derived aryl ethers, such as benzyl phenyl ether, dibenzyl ether, dinaphthalene ether, benzyl 2-naphthyl ether and 3-methoxyphenol.
研究领域:
化学工程
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催化材料科学
✓ 已验证
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2024
·
IF 5.6
Xialin Ji,Xiaoke Tian,Mengqing Zhou,Changzhou Chen,Jianchun Jiang
In this study, different kinds of lignin, including enzymatic hydrolysis of lignin (EHL), alkaline lignin (AL), kraft lignin (KL) and sodium lignosulfonate (LS) were investigated as precursor to prepare Ni@BTC@X (X= EHL, AL, KL, LS) catalysts using a traditional hydrothermal method with Ni-MOF for HDO upgrading of lignin derivative vanillin (VAN) to generate high value chemical 2-methoxy-4-methylphenol (MMP). The catalytic performance of these catalysts was investigated under different reaction conditions, and it was explored that the conversion of VAN was close to 100 % and the MMP yield was close to 90 % under the optimal conditions (Ni@BTC@LS catalyst, 220 ℃, 4 h, isopropanol, 2 MPa N 2 ). Various physical-chemical characterization results verified that the effects of active sites Ni, porous structure of lignin biochar support and electronic properties of the catalysts played a significiant role in HDO of lignin derived VAN. Additionally, synergistic effect of the highly homogeneously dispersed oxygen vacancies and acidic sites also promoted the VAN conversion efficiency. This work developed a strategy combing the advantages of MOFs and biomass derived substrates for manufacturing novel lignin/MOFs materials in the catalytic field.
研究领域:
化学工程
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环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2012
·
IF 4.525
Man Luo,Yong Liu,Juncheng Hu,Hang Liu,Jinlin Li
CdS and Ni-doped CdS hollow spheres were synthesized via a simple template-free one-pot method. The products were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, energy-dispersive spectroscopy analysis, X-ray photoelectron spectroscopy, and UV–vis absorption spectroscopy. The formation mechanism for the Ni-doped CdS hollow spheres was discussed. The prepared CdS and Ni-doped CdS hollow spheres showed the superior photocatalytic activity for the degradation of RhB under visible light (λ > 420 nm) irradiation, and 1.2 mol % Ni-doped CdS hollow spheres were found to be highly efficient for organic pollutants RhB and phenol removal. Moreover, this catalyst showed improved stability, and the activity did not decrease significantly after four recycles. The unique hollow spheres structure may favor the harvesting of exciting light due to multiple scattering within the interior space, and the doping of Ni2+ may facilitate the generation of electrons and holes pairs and inhibit their recombination rate by act as a temporary trapping sites of photoinduced electrons.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYHEDRON
·
2018
·
IF 2.067
Dejuan Fa,Mao Zhou,Hui Zhao,Yiwei Jiang,Yuqing Miao
The 3D flower-like Ni–Co–S was synthesized by a typical hydrothermal method in the presence of urea and thioacetamide. As comparison, the urchin-like Ni–Co–O was prepared in the absence of thioacetamide. The former processed higher electrocatalytic activity for methanol oxidation than the latter. Ni–Co–S exhibited the anodic peak current density of 19.23 mA/cm 2 for methanol oxidation, far higher than Ni–Co–O. It also showed the Tafel slopes of 57 mV/dec, much lower than Ni–Co–O. The BET results showed that the surface area and pore volume are 96.373 m 2 /g and 0.367 cm 3 /g for the flower-like Ni–Co–S, which is higher than 88.736 m 2 /g and 0.224 cm 3 /g for the urchin-like Ni–Co–O. As a result, the flower-like Ni–Co–S possessed more electroactive sites for methanol oxidation. The superhydrophobicity of the flower-like Ni–Co–S helps for the formation of micro air film on the surface of flower petals. Such a tri-phase interface of Ni–Co–S solid, reaction solution and air film may help for the electrocatalytic oxidation of Ni–Co–S toward methanol oxidation since the produced CO 2 can leave the surface of Ni–Co–S quickly and enter into solution phase due to the presence of air film and high solubility of CO 2 in aqueous solution.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Yang Liu,Xinyu Sun,Ying Wang,Shiqing Zhang,Fang Liu,Shaokai Ma,Jun Zhang,Ying Li,Yanming Xue,Chengchun Tang
Birnessite (δ-MnO 2 ), inspired by biological photosynthesis, holds promise as oxygen evolution reaction (OER) catalysts in water electrolysis for clean energy. Given that Mn 3+ serves as the active sites, various strategies have been employed to increase the Mn 3+ content to boost the OER activity. To surpass the limitations of the traditional adsorbate evolution mechanism (AEM), we have adopted an electrochemical reduction method to introduce metallic Ni and enrich oxygen vacancies onto δ-MnO 2 nanosheets. The resulting Ni/MnO 2 v /CC exhibits exceptional OER performance, with a reduction in overpotential by 190 mV (from 478 mV to 289 mV) at 10 mA cm −2 and a Tafel slope as low as 45 mV dec -1 , indicating accelerated catalytic activity. Experimental and theoretical analyses attribute this enhancement to a transition from the traditional AEM to lattice oxygen mechanism (LOM) mechanism. Moreover, the dual modification also enhances electronic conductivity, electrochemical surface area, and charge transfer ability of δ-MnO 2 . Our work offers a pathway to overcome conventional limitations in OER electrocatalysts, applicable not only to Mn-based catalysts but also to a range of other transition metal oxides.
研究领域:
能源材料
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电化学
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纳米科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Shiyong Xu,Mei Li,Ziyu Li,Meijuan Ding,Yijun Wang,Zhiliang Jin
NS-CQDs were synthesized by a hydrothermal method using high-sulfur lignite as the carbon source. Modification of Ni-MOF and Co/Zr-MOF using NS-CQDs to explore the performance of composite photocatalysts for hydrogen production . It was found that NS-CQDs significantly enhanced the hydrogen precipitation performance of the composite photocatalysts compared with the MOFs catalysts alone, and the highest hydrogen precipitation rate of the novel composite photocatalyst 5%NS-CQDs/NCZ2 reached 3662.68 μmol g −1 h −1 . It can be inferred from the conduction band and valence band positions of Ni-MOF, Co/Zr-MOF and NS-CQDs that a double S-type heterojunction is formed. The presence of thiophene and pyrrole nitrogen in NS-CQDs can promote electron transport , reduce the rate of electron-hole pair complexation, and improve the hydrogen evolution activity of the 5%NS-CQDs/NCZ2.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 22
·15487-15499
·
IF 2.993
Yang Ming,Rao Richuan
In this work, nonmetallic S was doped into hierarchical Ni(OH) 2 hollow microspheres by ethanol solvothermal method using thiourea as sulfur source. Although the morphology of precursor Ni(OH) 2 is maintained, the surface states and pore properties had greatly changed after S doping. Using the as-prepared S-doped Ni(OH) 2 as adsorbents for the removal of Congo red (CR), the S-doped Ni(OH) 2 exhibited much better adsorption capacity compared with undoped Ni(OH) 2 . The adsorption behavior of both Ni(OH) 2 and S-doped Ni(OH) 2 followed the pseudo-second-order kinetic model and intraparticle diffusion model. The equilibrium data of Ni(OH) 2 could be better fitted by Langmuir model, while Freundlich model could be better used to describe the S-doped Ni(OH) 2 with a much larger adsorption capacity toward CR. The tuned microstructure and changed surface states of adsorbent after S doping may be responsible for the enhanced adsorption performance. Therefore, the doping of S species into hierarchical Ni(OH) 2 paves a new way to tune the microstructure and surface states of Ni-based materials.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Qikai Ren,Shuaishuai Wang,Haoyu Liu,Xing Zhang,Yanran Cui,Gui-Rong Zhang,Lei Nie,Donghai Mei
The dry reforming of methane (DRM) serves as a pivotal reaction for hydrogen generation and the simultaneous conversion of methane and carbon dioxide, two major greenhouse gases, into syngas that can further be converted into high-value fuels and chemicals. However, catalyst deactivation imposes a major challenge that prohibits the market penetration of DRM. Here we reported a series of bifunctional Ni-Ce catalysts supported on SSZ-13 (Ni-Ce-SSZ-13) and discovered that a small amount of Ce could significantly enhance the activity, selectivity, and stability for DRM. Optimal ratio of Ni to Ce has been identified to yield peak catalytic performance. The optimal performance is correlated with the maximum Ce 3+ /Ce 4+ ratio as revealed by XPS analysis, which implies an increased presence of oxygen vacancies in the catalysts. It played a crucial role in facilitating the oxidation of activated CH 4 species at Ni sites, thereby enhancing DRM activity and diminishing the detrimental coke formation. It is also disclosed that integrating proper amount of Ce fosters its interactions with Ni, effectively preventing the agglomeration of Ni sites. This work presents great implications for the rational design and catalytic synergy of bi-/multi-functional zeolite catalysts for other technological applications.
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
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Bowen Lu,Ziqiang Han,Xinyu Zhi,Liqi Zhang
NiFe 2 O 4 exhibits excellent redox properties and is widely applied in catalytic reactions. However, rapid inactivation under reaction conditions limited its industrial applications. In this study, CeO 2 -NiFe 2 O 4 composite catalysts were synthesized, and the Reverse Water Gas Shift (RWGS) reaction was measured to reveal its CO 2 hydrogenation performance under a high-temperature condition. NiFe 2 O 4 catalysts got deactivated after being reduced to Fe-Ni alloy at 700 °C, decreasing the CO 2 conversion rate. CeO 2 addition can significantly improve its high-temperature activity, and 20CeO 2 -NiFe 2 O 4 exhibited the best catalytic activity (80.85 %, 700 °C). The CeO 2 -confined maintained Ni-Fe alloy with a relatively small crystal size and larger specific surface area, supporting more active sites for CO 2 hydrogenation. CeO 2 addition induced higher oxygen vacancy concentration, enhancing CO 2 activation and formates species formed on 20CeO 2 -NiFe 2 O 4 , resulting in higher CO 2 conversion activity. In addition, 20CeO 2 -NiFe 2 O 4 maintained its catalytic stability for 50 h at 700 °C. The CeO 2 confined enhanced the high-temperature stability of Fe-Ni alloy. CeO 2 and formed CeFeO 3 dispersed in 20CeO 2 -NiFe 2 O 4 inhibited excessive aggregation of Fe-Ni alloy, and CeO 2 inhibited carbon deposition on Fe-Ni alloy, improving Fe-Ni alloy’s reaction stability under RWGS reaction conditions. CeO 2 confined may give insight into improving metal stability under high-temperature and reductive conditions in heterogeneous catalysis.
研究领域:
催化化学
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材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Materials Chemistry Frontiers
·
2024
·
IF 6
Mohit Kumar,Bhimanaboina Ramulu,Jae Su Yu
To produce clean and green hydrogen energy from electrolytic water, better electrocatalytic materials need to be developed. Herein, we reported the development of a Ti3C2 MXene@Ni/Co sulfide hybrid material for the use in hydrogen evolution reaction (HER) process, which is effective and stable. The shape of metal sulfide and its interactions with Ti3C2 MXene caused electronic coupling. This increased both the exposed metal sulfide's active edge sites and the charge-transfer speed. When compared with pure MXene and Ti3C2 MXene@NiS nanostructure, Ti3C2 MXene@Co4S3 exhibited outstanding electrocatalytic activity and stability in the HER process. The unique properties of the skeletal structure and the robust interface interaction between Co4S3 and MXene are responsible for the superior performance of Ti3C2 MXene@Co4S3 in the HER process. Our research offers a practical method to synthesize specialized nanostructures for electrocatalysis, electronics, and other applications.
研究领域:
材料科学
·
能源科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Wangchang Geng,Pengfei Song,Xinrou Cao,Libing Duan
Metal-organic frameworks (MOFs)-derived metal oxides are characterized by high porosity, large specific surface area, controllable composition, and tunable pore size, which make them have good potential as gas sensing materials. In this paper, Ni 3 V 2 O 8 @NiO hollow microspheres derived from bimetallic Ni/V-MOFs were synthesized using a three-step method (solvothermal method, cation-exchange method, and annealing process). XRD, Raman, SEM, TEM, XPS, and BET techniques were employed to investigate the structure, morphology, specific surface area, pore size distributions, elemental composition, and chemical state of Ni 3 V 2 O 8 @NiO composites. Gas sensing performance studies showed that the NV@NiO-2 sensor exhibited higher response (43.7) to 100 ppm triethylamine at a lower operating temperature (240℃), shorter response/recovery time (88 s/127 s), higher selectivity, lower detection limit (4.5 ppb), and better repeatability. In addition, the NV@NiO-2 sensor exhibited a strong linear relationship (R 2 = 0.996) between response and gas concentration across a range of 1–100 ppm. The present work serves as a valuable reference for the preparation of triethylamine sensing materials with high specific surface area, high porosity, high response and high selectivity.
研究领域:
材料科学
·
化学传感器
✓ 已验证
产品关联
DOI
高影响因子
APPLIED ENERGY
·
2017
·
IF 7.182
Xinghua Zhang,Wenwu Tang,Qi Zhang,Tiejun Wang,Longlong Ma
Ni-based catalysts supported on γ-Al 2 O 3 and SiO 2 were prepared by impregnation. Catalyst characterization was performed using XRD, NH 3 -TPD, H 2 -TPR and chemisorption. Effects of supports on catalytic performance were tested using the hydrodeoxygenation (HDO) of phenolic compounds as a model reaction. Experiment result shows that single phenolic compounds can be converted via HDO reaction over Ni/SiO 2 and Ni/γ-Al 2 O 3 catalysts at 300 °C. The hydrocarbon yields are in the range of 60–90%. The effect of supports on the reaction mechanism was also explored. It is found that hydrogenation of the aromatic ring preferentially occurs over Ni/SiO 2 catalyst while the cleavage of C AR O bond preferentially occurs over Ni/γ-Al 2 O 3 catalyst in the HDO of phenol. Compared to Ni/γ-Al 2 O 3 catalyst, Ni/SiO 2 catalyst exhibits better repeatability and higher catalytic activity for hydrocarbon yield when mixed phenolic compounds were used as feedstock in the HDO reaction, and the carbon deposited on the surface of Ni/SiO 2 catalyst is lower.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）