CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Zhiqiang Zhou,Xiumin Chen,Zhongqian Zhao,Youli Xu,Bingyang He,Li Liu,Bin Yang,Baoqiang Xu,Dachun Liu
The Ab initio molecular dynamics (AIMD) simulation was adopted to elucidate the alumina vacuum carbothermal reduction and nitridation (VCRN) reaction mechanism, and an experimental method was adopted to verify the AIMD results. According to the results, the VCRN reaction occurs only when N 2 is adsorbed on both the C and Al atoms. C plays two important roles during the reaction of alumina VCRN: one is to act as a charge exchange carrier for N and Al atoms to catalyze N 2 molecule decomposition, and the other is to react with O atoms and reduce Al 2 O 3 .
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
APPLIED CATALYSIS A-GENERAL
·
2023
·
IF 5.5
Zhecheng Fang,Haoan Fan,Xuezhi Zhao,Gaobo Lin,Bolong Li,Jianghao Wang,Xiuyang Lu,Wulong Yang,Mian Li,Weiyu Song,Jie Fu
Glucose hydrogenation to sorbitol is a vital industrial reaction for the utilization of biomass. Generally, hydrogenation is catalyzed by the inexpensive Raney Ni catalyst which has good catalytic but suffers from poor stability and side reaction，and the mechanisms of glucose hydrogenation on Raney Ni surfaces is also unclear. This study combines density functional theory calculations, ab initio molecular dynamics simulations (AIMD), and experiments to reveal the nature of glucose hydrogenation on the (111), (200), and (220) surfaces of Ni catalyst. The DFT calculation results show that the (111) and (200) surfaces of Raney Ni are favorable for hydrogenation with 111-η2, 200-η2–1, 200-η2–3 adsorption configurations and adsorption energy is closely related to the rate-determining step. Furthermore, in-situ IR analysis and AIMD calculation confirm the existence of 111-η2 structure in hydrogenation, while electronic analysis demonstrates that improving the alignment of the nickel surface's d orbitals with the -C O bond's π orbitals can enhance both the adsorption and catalytic hydrogenation activity. In addition, the (220) surface is found to be responsible for the dehydrogenation of cyclic-glucose, and decreasing the percentage of the (220) surface and increasing the reaction temperature appropriately may be effective in inhibiting the side reaction. This paper not only reveals the nature of Raney Ni catalyzed glucose hydrogenation but also lights the direction for the design of highly efficient nickel-based catalysts.
研究领域:
化学工程
·
催化科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CORROSION SCIENCE
·
2025
·
IF 8.5
Z.N. Jiang,J.M. Duan,S.Y. Tian,R.Y. Xue,C.F. Dong,G.A. Zhang
A green corrosion inhibitor, (2 E , 4 E )-2-cyano-5-phenyl-2,4-pentadienoic acid (CPPA), was synthesized via one-step modification of cinnamaldehyde. CPPA exhibits outstanding inhibition effect for mild steel (MS) in HCl medium with an inhibition efficiency of 98.83 % at a concentration of 0.6 mM with good inhibition stability. The inhibition mechanism of CPPA was elucidated by combining surface characterization techniques with ab initio molecular dynamics (AIMD) simulations. XPS and ToF-SIMS analyses indicate that CPPA molecules could adsorb on MS surface by covalent bonding through N, C, and O atoms. AIMD simulations reveal that CPPA approaches to steel surface motivated by van der Waals force, i.e., physisorption occurs. Subsequently, the physisorption of CPPA is transformed into a strong and stable chemisorption, which was demonstrated by IGMH, CPPA-Fe bond length, electron density difference and PDOS characteristics. The adsorbed CPPA film significantly improves the hydrophobicity of MS surface, and acts as a shield to effectively hinder the diffusion and access of corrosive particles to steel surface, thus exhibiting outstanding and stable corrosion inhibition performance.
研究领域:
材料科学
·
腐蚀工程
·
表面化学
·
计算化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Hui Zhang,Qiang Fu,Hongyun Qin,Xia Chen,Qicheng Zhang,Zixu Dong,Haoyuan Li,Shoudong Wang,Ming Wang
Hydrogen recovery from ammonia purge gas is a desirable method to relieve the pressure of increasing demand for hydrogen. Metal-organic frameworks (MOFs) are promising adsorbents for the separation of the H 2 –N 2 mixture. However, the separation of the H 2 –N 2 mixture using MOFs remains challenging due to the lack of adsorptive mechanism. Herein, the adsorption mechanism of the H 2 –N 2 mixture in SIFSIX-2-Cu-i has been systematically investigated with the method of a combination of excess adsorption experiments, molecular simulations , and DFT calculations. In the Grand Canonical Monte Carlo (GCMC) simulations, the polarizable force field was first applied to the adsorption of pure H 2 or N 2 and H 2 –N 2 mixture in SIFSIX-2-Cu-i. Ab Initio Molecular Dynamics (AIMD) was performed to investigate the distribution of the guest molecules in the pores of SIFSIX-2-Cu-i. Finally, Density functional theory (DFT) calculations were performed to predict the transfer of charge between MOF and guest molecules. Results revealed two binding sites of H 2 or N 2 in SIFSIX-2-Cu-i. A relatively high thermodynamic adsorption selectivity for N 2 over H 2 has been observed in SIFSIX-2-Cu-i. Furthermore, SIFSIX-2-Cu-i also exhibits a greater affinity with N 2 than with H 2 , which is probably because of the stronger induction interactions between F2 atoms and N 2 molecules. These findings are of significance to guide the design of the new highly selective adsorbents for the separation of H 2 /N 2 .
研究领域:
化学工程
·
材料科学
·
物理化学
✓ 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）