JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 11
·116518
·
IF 4.316
Peipei Li,Dan Cheng,Xiaohua Zhu,Meiling Liu,Youyu Zhang
Compared with the traditional Haber-Bosch process, electrochemical N2 to NH3 reduction affords an eco-friendly and sustainable alternative to ambient NH3 synthesis with the aid of efficient electrocatalysts. In this work, partial oxidation of MnS to obtain the MnS-Mn3O4 is proved as a promising noble-free electrocatalysts of N2 to NH3 fixation at ambient conditions. When tested in 0.1 M Na2SO4, the electrochemical N2 reduction reaction performance of MnS-Mn3O4 is improved comparing with the MnS, which achieves large NH3 yield of 16.74 μg h–1 mgcat.–1 and a high Faradaic efficiency of 5.72%. It also exhibits excellent selectivity of N2 to NH3 and strong long-term electrochemical stability.
研究领域:
化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 10
·1146
·
IF 4.501
Jikang Yao,Yuanjie Xu,Hua Yang,Zhuangzhuang Ren,Lizhi Wu,Yu Tang
The partial oxidation of methane (POM) is a promising method for converting methane to syngas. The transition metal supported on boron nitride (BN) has recently been studied as part of a catalog of emerging catalysts. However, the chemical state of the metal supported on BN during methane reforming is still in debate. In this work, we report a rhodium catalyst on boron nitride (Rh/BN) for the POM, with exceptional activity and long-term stability at 600 °C for 230 h. The Rh/BN catalyst was investigated by X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy, and diffuse reflectance infrared Fourier transformed spectroscopy (DRIFTS). As revealed by in situ DRIFTS, the infrared band (2020 cm−1) of the product molecule, CO, adsorbed on the Rh, as the probe confirms the metallic state of Rh during the POM reaction. In addition, the results of in situ DRIFTS indicate that the reactive gaseous environment would react with the catalyst to form B-OH and B-H, which synergistically boost the POM activity.Keywords:partial oxidation of methane;syngas;boron nitride;rhodium;DRIFTS
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2020
·
IF 3.871
Xianhua Zhang,Yinghui Su,Chunlei Pei,Zhi-Jian Zhao,Rui Liu,Jinlong Gong
Chemical looping steam reforming of methane (CL-SRM) has emerged as an attractive pathway on H 2 O splitting for H 2 production. However, this process still faces a major challenge in efficiently producing H 2 with high redox kinetics and yields. In this paper, the promoting effects of Ce 3+ substitution into LaFeO 3 redox catalysts on thermochemical H 2 O splitting as well as partial oxidation of methane are presented. An appropriate amount of Ce 3+ substitution in A site of LaFeO 3 (La 0.5 Ce 0.5 FeO 3 ) promotes the lattice oxygen conversion rate in methane partial oxidation step and boosts the reaction kinetics in H 2 O splitting step by enhancing the surface water activation and lattice oxygen mobility of the perovskite. In the CL-SRM process, the perovskite is reduced into Fe 0 /(La 0.5 Ce 0.5 ) 2 O 3 and Fe 0 /(La 0.5 Ce 0.5 )O 2- x phases in methane partial oxidation step and recovered to the original perovskite structure in H 2 O splitting step with simultaneous production of hydrogen, which maintains a reversible phase transformation during 100 redox cycles. As a result, the La 0.5 Ce 0.5 FeO 3 achieves high stability with the superior performance for syngas and hydrogen production. These findings provide the fundamental understanding on the synergy between the catalytic sites and enhanced lattice oxygen mobility for the promotion of H 2 O activation and hydrogen productivity in chemical looping process.
研究领域:
化学工程
·
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Li Zhang,Yue Hu,Weibin Xu,Chuande Huang,Yang Su,Ming Tian,Yanyan Zhu,Huimin Gong,Xiaodong Wang
Iron-based oxides are promising oxygen carriers for chemical looping syngas production from methane; however, facile coke formation over reduced metallic Fe0 largely limits the syngas productivity. This work demonstrates that the introduction of Sn promoters into BaFe1–xSnxO3−δ perovskite oxides significantly restrains coke formation and improves the syngas yield to above 19.2 mmol/g with a H2/CO ratio of 2, which is 2.9-fold in comparison to BaFeO3−δ. Characterization results suggest that Sn cations are well-confined in the perovskite matrix by substitution of Fe. The Fe cations serve as main active sites for C–H bond activation with Sn cations as an oxygen reservoir, which donate the neighboring lattice oxygen to active Fe for selective methane oxidation. Besides, an intimate Fe–Sn interaction induces the formation of the FeSn alloy rather than metallic Fe0 under a reducing atmosphere, which restrains methane pyrolysis and notably improves the coke resistance. When Sn loading (x) increases to above 0.6, all Fe cations can be deeply reduced to the metallic state without coke accumulation and oxygen storage capacity reaches as high as ca. 6.5 mmol/g with nearly 100% syngas selectivity, which breaks the “seesaw” effect between oxygen supply and syngas selectivity for traditional iron-based materials. These results provide meaningful guidance for fabricating prospective oxygen carriers or catalysts with better anti-coke property for the chemical looping process or specific catalytic reactions.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2019
·Vol. 9
·期 7
·606
·
IF 3.444
Chuanmin Ding,Junwen Wang,Yufeng Li,Qian Ma,Lichao Ma,Jing Guo,Zili Ma,Ping Liu,Kan Zhang
The supporting modes of active metal over mesoporous materials play an important role in catalytic performance. The location of Ni nanoparticles inside or outside the mesoporous channel of MCM-41 has a significant influence on the reactivity in partial oxidation of methane to syngas reaction. The characterization data using different techniques (Transmission Electron Microscope (TEM), X-Ray Diffraction (XRD), N2adsorption-desorption, H2Temperature-Programmed Reduction (H2-TPR), and Inductively Coupled Plasma (ICP)) indicated that nickel was located outside the mesoporous channels for the impregnation method (Ni/MCM-41), while nickel was encapsulated within MCM-41 via the one-step hydrothermal crystallization method (Ni-MCM-41). The nickel atoms were mainly dispersed predominantly inside the skeleton of zeolite. When the load amount of Ni increased, both of Ni species inside the skeleton or pore channel of zeolite increased, and the ordered structure of MCM-41 was destroyed gradually. Contributed by the strong interaction with MCM-41, the Ni particles of Ni-MCM-41 were highly dispersed with smaller particle size compared with supported Ni/MCM-41 catalyst. The Ni-MCM-41 displayed higher catalytic performance than Ni/MCM-41, especially 10% Ni-MCM-41 due to high dispersity of Ni. The confinement effect of MCM-41 zeolite also afforded high resistance of sintering and coking for 10% Ni-MCM-41 catalyst. Especially, 10% Ni-MCM-41 catalyst showed outstanding catalytic stability.Keywords:partial oxidation of methane;sintering and coking resistance;Ni location;confinement effect;MCM-41 zeolite
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Yuanjie Xu,Rong Chen,Hongqiao Lin,Qian Lv,Bo Liu,Lizhi Wu,Li Tan,Yihu Dai,Xupeng Zong,Yu Tang
Catalyst interface determines the activity and stability of partial oxidation of methane (POM) toward syngas under high temperatures crucially. Herein, Ni catalysts supported on CeO 2 were prepared under different pretreatment atmospheres to construct an optimal and robust interface. Ni/CeO 2 catalyst pretreated in H 2 (Ni/CeO 2 -H 2 ) exhibits the higher activity and the better stability than Ni/CeO 2 -Ar and Ni/CeO 2 -air catalysts. The Ni-O-Ce interfacial site in Ni/CeO 2 -H 2 catalyst shows the lower reduction temperature, indicating the enhanced H-spillover effect and enhanced oxidation resistance of Ni under POM conditions. Moreover, the XPS and in situ Raman results show that Ni/CeO 2 -H 2 contains more surface oxygen vacancies for adsorbing and activating oxygen, further contributing to the reaction activity. The in situ DRIFTS results indicate that the CH 4 could react with the lattice oxygen to form formate and carbonate, and further decompose to CO and CO 2 . These findings deepen the fundamental understanding of Ni/CeO 2 catalysts for POM reaction.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2018
·
IF 3.441
Xuewu Jia,Feng Sun,Yi Fei,Manping Jin,Fan Zhang,Wei Xu,Ning Shi,Zhiguo Lv
The explosive properties of mixtures of aqueous hydrogen peroxide (H 2 O 2 ) and working solution (WS), and the main components of the working solution (1, 3, 5-trimethyl benzene(TMB), trioctylphosphate (TOP)) were investigated by the drop weight test. The explosion range was interpreted by thermal calculation, and the calculated results agreed well with the experimental test. The explosion mechanism of the TMB/H 2 O 2 mixture is the partial oxidation of TMB by H 2 O 2 , which is qualitatively obtained by analyzing the gaseous and liquid products of the TMB/ H 2 O 2 mixture after explosion. Finally, a proposed explosion mechanism was suggested.
研究领域:
化学工程
·
安全科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2024
·
IF 11.3
Rongjiang Zhang,Gen Liu,Cunbao Huo,Jia Liu,Bo Zhang,Bolun Yang,Xiaoyong Tian,Zhiqiang Wu
Perovskite oxygen carriers in a methane chemical looping partial oxidation process enable high reactivity over 850 °C. Lowering the reaction temperature helps to circumvent energy dissipation and couple the above-mentioned process with energy-efficient systems. This paper demonstrates the attractive oxygen-donating capacity of Fe–Ni-based perovskite oxygen carriers for methane partial oxidation. The aforesaid process exhibits more than 70% methane conversion and 6.71 mmol·g–1 unit syngas yield at 700 °C, using LaFe0.5Ni0.5O3. This impressive high reactivity mainly originates from the lowered lattice oxygen bonding strength and the spontaneously constructed active Ni-rich surface of perovskite oxides by Ni doping. In addition to the outward migration of lattice oxygen, active metal elements, such as Ni, continuously segregate to the surface with the reduction of perovskite oxides, promoting methane partial oxidation. We speculate that the chemical looping reaction pathway consists of consecutive competitive reactions based on analysis of the real-time product distribution and the dynamic evolution of oxygen carriers. Highly selective syngas production can be achieved on LaFe0.5Ni0.5O3 by reducing reaction temperatures or increasing space velocity to balance methane dissociation and lattice oxygen release kinetics. Irreversible Ni segregation and phase-separation-induced inert La2O3 on the surface of perovskite oxides during redox cycles are responsible for the cyclic performance degradation of oxygen carriers. This work offers intriguing references to design perovskite oxygen carriers for intensifying the medium-temperature chemical looping partial oxidation process.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2014
·
IF 2.93
Haijun Guo,Fen Peng,Hairong Zhang,Lian Xiong,Shanggui Li,Can Wang,Bo Wang,Xinde Chen,Yong Chen
High efficient production of lower alcohols (C 1 –C 5 mixed alcohols) from hydrogen rich bio-oil derived syngas was achieved in this work. A non-catalytic partial oxidation (NPOX) gasification technology was successfully applied in the production and conditioning of bio-oil derived syngas using bio-oil (BO) and emulsifying waste engine oil (EWEO) as feedstock . The effects of water addition and feedstock composition on the gasification performances were investigated. When the BO 20 and EWEO 30 was mixed with mass ratio of 1: 0.33, the maximum hydrogen yield of 93.7% with carbon conversion of 96.7% was obtained, and the hydrogen rich bio-oil derived syngas was effectively produced. Furthermore, a two-stage bed reactor was applied in the downstream process of lower alcohols synthesis from hydrogen rich bio-oil derived syngas (H 2 /CO/CO 2 /CH 4 /N 2 = 52.2/19.5/3.0/9.4/15.9, v/v). The highest carbon conversion of 42.5% and the maximum alcohol yield of 0.18 kg/kg cat h with selectivity of 53.8 wt% were obtained over the Cu/ZnO/Al 2 O 3 (2.5)//Cu 25 Fe 22 Co 3 K 3 /SiO 2 (2.5) catalyst combination system. The mechanism and evaluation for lower alcohols synthesis from model bio-oil derived syngas and model mixture gas were also discussed. The integrative process of hydrogen rich bio-oil derived syngas production and downstream lower alcohols synthesis, potentially providing a promising route for the conversion of organic wastes into high performance fuels and high value-added chemicals.
研究领域:
能源与燃料
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2020
·Vol. 10
·期 2
·278
·
IF 4.324
Guiping Li,Yongli Wang,Jingtao Bi,Xin Huang,Yafei Mao,Liang Luo,Hongxun Hao
In this work, a facile oxidation strategy was developed to prepare novel tungsten disulfide/tungsten trioxide (WS2/WO3) heterostructures for adsorbing organic dyes efficiently by combining the hydrophilic property of WO3and the superior dye affinity of WS2. The structural and elemental properties of the synthesized hybrid materials were systematically investigated, and the results demonstrated the retained flower-like morphology of the primitive WS2and the successful introduction of WO3. Furthermore, surface properties such as a superior hydrophilicity and negative-charged potential were also demonstrated by a water contact angle characterization combined with a Zeta potential analysis. The performance of the obtained WS2/WO3hybrid materials for removing Rhodamine B (RhB) from wastewater was evaluated. The results showed that the maximum adsorption capacity of the newly synthesized material could reach 237.1 mg/g. Besides, the adsorption isotherms were also simulated by a statistical physics monolayer model, which revealed the non-horizontal orientation of adsorbates and endothermic physical interaction. Finally, the adsorption mechanism and the recyclability revealed that the partial oxidation strategy could contribute to a higher adsorption capacity by modulating the surface properties and could be applied as a highly efficient strategy to design other transition metal dichalcogenides (TMDs) heterostructures for removing organic dyes from wastewater.Keywords:WS2/WO3heterostructure;surface property;partial oxidation;hydrophilicity;adsorption mechanism
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTAL GROWTH & DESIGN
·
2024
·
IF 3.2
Shuang Xiao,Chunyan Wang,Teng You,Ping Huang,Qiuxia Deng,Ping Jiang,Peng Chen,Daiping He
It is highly desirable but still remains challenging to tune nanozymes with superior catalytic activity via simple operation. Herein, the oxidase-like activity of Ru nanoparticles supported on porous carbon (Ru/PC) was significantly modulated via a facile partial oxidation process. Due to the small size, uniform dispersion, high electron density on the surface, as well as abundant interfacial heterostructure between Ru and RuO2, the partially oxidized Ru/PC (P–Ru/PC) showed excellent oxidase-mimicking activity in triggering 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation, with a low Km of 0.138 mM and a high Vmax of 2.82 × 10–7 M·s–1. Theoretical calculations reveal that both the absorption and subsequent activation of molecular oxygen are more favorable on the interfacial heterostructure of P–Ru/PC than on the Ru/PC surface. Moreover, the oxidase-like activity of P–Ru/PC was found to be suppressed by melatonin, along with a fading color of oxidized TMB (TMBox). As a result, a novel colorimetric system consisting of P–Ru/PC and TMB was established for melatonin detection for the first time, which shows a wide linear range of 10–220 μM and a low detection limit of 0.023 μM. This work not only provides a simple but smart strategy of interface engineering to tune the oxidase-like activity of Ru/PC, but also expands the application of Ru oxidase mimics in pharmaceutical analysis.
研究领域:
纳米材料科学
·
生物分析化学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2017
·
IF 10.614
Sai Chen,Liang Zeng,Hao Tian,Xinyu Li,Jinlong Gong
Partially oxidizing methane into syngas via a two-step chemical looping scheme is a promising option for methane transformation. Providing the optimum lattice oxygen to selectively produce syngas represents the major challenge for the development of oxygen carrier materials in chemical looping processes. This paper describes the design of WO3-based oxygen carriers as the primary source of lattice oxygen with high melting points and attractive syngas selectivity. To further enhance the lattice oxygen availability and methane conversion capacity, NiO nanoclusters are introduced, considering the doping effect on chemical bonding disruption in both bulk and surface regions. For Ni0.5WOx/Al2O3, the nickel cations incorporated into the bulk of WO3 can strongly weaken the tungsten–oxygen bond strength and increase the availability of lattice oxygen. The surface-grafted nickel species can effectively activate methane molecules and catalyze the partial oxidation reaction. Total methane conversion and syngas yield can be substantially increased by about 2.7-fold in comparison with unmodified WO3/Al2O3. This work demonstrates that the bulk and surface modifications are feasible to tailor the active lattice oxygen of oxygen-carrying materials in chemical looping processes.
研究领域:
催化化学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）