Science China-Information Sciences
·
2024
·Vol. 67
·期 5
·1-9
·
IF 7.3
Liang Jieyuan,Zou Zixing,Liang Junwu,Wang Di,Wang Biao,Chu Anshi,Yi Jiali,Zhang Cheng,Fang Lizhen,Zhang Tian,Liu Huawei,Zhu Xiaoli,Li Dong,Pan Anlian
Bilayer transition metal dichalcogenides (TMDs) balance the high mobility of single layers with the high state density of multilayers and therefore have promising application prospects in high-performance electronics. However, the layer-controlled growth of 2D materials is still confronted with challenges such as poor repeatability between different labs and a limited understanding of the growth mechanism at the atomic scale. Herein, we report a new carbon-assisted chemical vapor deposition process that can realize the growth of WS 2 sheets with high yield, precise thickness controllability, and repeatability. We show that carbon can act as a reducing agent and catalyst that preferentially reacts with the WO 3 precursor to form intermediate WO 3− x products with low-valence state W. The resulting oxycarbide gas has a low surface adsorption energy when deposited on the surface of as-grown WS 2 , which provides nucleation sites for the subsequent layer of WS 2 growth and leads to the vertical growth of WS 2 sheets. The growth mechanism is thoroughly investigated. Electrical transport measurements show that the produced bilayer WS 2 possesses a high carrier mobility (up to 58 cm 2 ·V −1 ·s −1 ) and small subthreshold swing (estimated to be 148 mV/decade), which are among the best reported results for TMDs produced using CVD.
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2020
·Vol. 132
·期 1
·417-429
·
IF 1.52
Xie Qi,Miao Changxi,Lei Tianqi,Hua Weiming,Yue Yinghong,Gao Zi
Dehydrogenation of ethane assisted by CO 2 has been investigated over Au catalyst supported on Y-doped CeO 2 nanorod. The catalysts were characterized by XRD, TEM, N 2 adsorption, XPS, TG, H 2 -TPR and Raman spectroscopy. Enhanced activity can be obtained after the proper Y doping. The optimal catalyst Au/Ce 0.9 Y 0.1 exhibits an ethane conversion of 20.9% and nearly 100% selectivity to ethylene without any evident tendency of deactivation in 50 h. The reducibility of surface oxygen species is found to play a key role in the dehydrogenation assisted by CO 2 , which can be improved by proper Y doping into CeO 2 nanorod. The promoting effect of CO 2 on activity is evident over Au/Ce 0.9 Y 0.1 catalyst, due to the quick transformation of H 2 product into H 2 O by the reverse water gas shift reaction. The catalyst stability is also improved by the addition of CO 2 , attributed to the elimination of coke by Bouduoard reaction.
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
FUEL
·
2023
·
IF 7.4
Haipeng Liu,Haifeng Jiang,Jiaxing Song,Ling Zhang,Yu Zhang,Yuhang Li,Wenpeng Hong
The production of high value-added liquid products by catalytic pyrolysis of cellulose has become an effective way to realize the efficient utilization of biomass. This work synthesized a series of Co-Ce, Co-Fe and Co-Mg composite metal catalysts and used them to obtain furans and ketones production. In addition, the CO 2 was used as a pyrolysis atmosphere to investigate the synergistic effect between CO 2 and the prepared catalyst. The results showed that the catalyst effectively promoted the depolymerization of cellulose and improved the oxygen transfer behavior between volatile matters during cellulose pyrolysis. As a reaction medium, CO 2 influenced the carbon distribution of products, thereby increasing syngas yield, and the CO 2 atmosphere promoted the formation of furans and ketones. Compared with those obtained by the non-catalytic pyrolysis in N 2 atmosphere, the relative contents of furans and ketones in the liquid products produced by the catalytic pyrolysis of cellulose in CO 2 atmosphere increased by about 13.38% and 9.8%. In the CO 2 environment, the generation ability for furans was Co-Mg catalyst > Co-Ce catalyst > Co-Fe catalyst, and the generation ability for ketones was Co-Ce catalyst > Co-Mg catalyst > Co-Fe catalyst. These works provide an important way for the efficient preparation of furans and ketones from biomass pyrolysis.
研究领域:
能源与环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2016
·Vol. 163
·期 11
·F3029
·
IF 3.014
Haoran Xu,Bin Chen,Meng Ni
Syngas can be produced from H2O/CO2 co-electrolysis using an SOEC. However, H2 and CO are both produced in the cathode and the electricity consumption is large. In this paper, direct carbon-assisted SOEC for H2O electrolysis (DC-SOFEC) is proposed for cogenerating electricity power and syngas with easy control of H2/CO ratio. A 2D numerical model is developed to study the effects of operating and design parameters on the DC-SOFEC performance. The model is validated with experimental data for direct carbon solid oxide fuel cell. One important finding is that the carbon assisting is effective in lowering the equilibrium potential of SOEC, thus greatly reduces the electrical power consumption for H2O electrolysis. The DC-SOFEC can generate electrical power, CO and H2 simultaneously at a low current density and sufficiently high temperature. Compared with conventional SOEC for H2O/CO2 co-electrolysis, DC-SOFEC is advantageous as CO and H2 are produced in the anode and cathode, respectively. This enables easy control of H2/CO ratio, which is helpful for subsequent processes to synthesize other chemicals or fuels from syngas. Besides, DC-SOFEC can actually produce electricity rather than consuming it. The model can be used for subsequent design optimization of SOFEC for effective energy storage and conversion.
研究领域:
能源科学
·
化学工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Jing Wang,Wen Zhang,Zemeng Dong,Ning Zhang,Qiong Zhang,Congxia Xie,Zexing Wu,Guang-Rui Xu,Lei Wang
Pd-based catalysts have received wide attention due to their outstanding anti-CO poisoning property, whereas the structural instability limits their application. The hierarchical porous PdRuCu nanosheets (HP PdRuCu NSs) with large electrochemically active surface area, abundant active sites, and stable structures are synthesized through continuous access to CO bubbles. HP PdRuCu NSs exhibit excellent hydrogen evolution reaction (HER) catalytic activity with an ultralow overpotential of 25 mV at 10 mA cm −2 and a Tafel slope of 87.5 mV dec −1 in alkaline·media. Meanwhile, the peak mass activity and specific activity of HP PdRuCu NSs for glycerol oxidation reaction (GOR) are 1083 mA mg −1 Pd and 38.8 A m −2 , respectively, superior to that of PdRu nanosheets (PdRu NSs), Pd nanosheets (Pd NSs), and commercial Pd black. The introduction of Ru and Cu atoms facilitates the C–C bond cleavage and the complete oxidation of glycerol to CO 2 , as well as the accelerated oxidation/removal of the poisonous CO ads in between.
研究领域:
材料科学
·
电催化领域
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Xiuquan Li,Zhongqing Yang,Li Zhang,Ziqiang He,Yunfei Yan,Jingyu Ran,Zukhra C. Kadirova
The catalytic reaction of ethane with CO 2 promotes the value-added conversion of natural gas and the resource utilization of greenhouse gases. In this work, the CO 2 -assisted ethane dehydrogenation reaction characteristics on Fe 1.5 Ni 0.5 /ZrO 2 (M, T, Mix) catalyst with different crystal plane structure were studied through catalyst activity test, catalytic reaction kinetics study and catalyst characterization analysis. It is found that the exposed crystal faces of the ZrO 2 -supported catalyst has a significant effect on the CO 2 -assisted ethane oxidative dehydrogenation reaction. The monoclinic phase Fe 1.5 Ni 0.5 /ZrO 2 -M catalyst exhibits the largest conversion of ethane (21.8%) and CO 2 (25.2%) and the maximum selectivity to C 2 H 4 (80.5%). Monoclinic phase of ZrO 2 selectively exposes the ( −1 1 1) and (1 1 1) low-index surfaces with higher oxygen vacancy (O v ) density and stronger metal-support interaction, which leads to the formation of more Fe x Zr 1-x O 2 structures with high catalytic activity. The reductive oxygen vacancy O v and Fe 2+ -O-Zr 3+ sites promote the activation of CO 2 through the cleavage of C=O bond to supplement O* species. The O* species on the oxidative Fe 3+ -O-Zr 4+ site are captured and combined with H* species derived from the selective cleavage of ethane C–H bond to generate H 2 O.
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 SUPERCRITICAL FLUIDS
·
2016
·
IF 2.579
Teng Ma,Yu S. Zhang,Ai-Zheng Chen,Jie Ju,Chen-Wei Gu,Ranjith Kumar Kankala,Shi-Bin Wang
A cell-friendly strategy based on the subcritical carbon dioxide (Sub-CO 2 ) sintering was developed for convenient single-step bioassembly of scaffolds from cellularized poly(lactic-co-glycolic acid) (PLGA) porous microspheres. The method has provided a versatile strategy to utilize the hierarchical voids of the scaffold, which allowed seeded cells to proliferate for 14 days (cartilage cells) and 21 days (fibroblasts), respectively. Furthermore, confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) images indicated that the cartilage cells favored the surface of the porous microspheres, while the fibroblasts tended to grow into the porous microspheres and attach onto the walls of the inner pores. This modular strategy provides a convenient way to seed cells prior to bulk scaffold fabrication as the Sub-CO 2 processing is benign to cells, which will potentially find widespread applications in tissue engineering and regenerative medicine.
研究领域:
组织工程
·
再生医学
·
生物材料科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2025
·
IF 8.3
Runze Wang,Tengpeng Wang,Fangsheng Liu,Yuyao Ma,Tao Wei,Dehua Dong
Carbon-assisted solid oxide electrolysis cell (CA-SOEC) presents a promising solution for water electrolysis with reduced energy consumption and enhanced efficiency of hydrogen production. However, one key issue in optimizing CA-SOEC performance is the inefficient mass transfer at the anode layer, particularly in improving the CO–CO 2 shuttle mechanism. To address this issue, this study designs a dendritic channel anode for CA-SOEC, which significantly enhances the CO–CO 2 shuttle, realizing improved mass transfer and reduced polarization resistance. Further, an additional Pd/GDC-Ni nano-catalyst layer was incorporated at the electrode-electrolyte interface, which greatly improved the efficiency and stability of anode layer for long-term electrolysis process, presenting a current density of 1.41 A cm −2 under a low voltage of 1.0 V. This research will help to provide new ideas and technical support for the design of highly efficient and environmentally friendly anode layer of CA-SOEC for water electrolysis.
研究领域:
能源材料科学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
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