Processes
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2023
·Vol. 11
·期 3
·703
·
IF 3.5
Liang Shen,Jiabao Gong,Yifang Liu,Erle Qiao
The molecular structure of cationic surfactants is closely related to their flotation performance. In this paper, three cationic surfactants with different head group structures were selected as collectors of kaolinite, and the substituent effects were studied by the DFT method. The DFT calculation results showed that increasing the number of substituents in the dodecylamine head group can significantly increase its surface and head group charge. Dodecylamine has the lowest LUMO orbital energy, so dodecylamine has the strongest electron attraction ability and the strongest interaction with kaolinite. Electron density differential showed that there was an area of electron aggregation between the collector and the surface of the kaolinite. The interaction energy of DDA on kaolinite surfaces was greater than that of the other two collectors, indicating that the adsorption of DDA on the surface of kaolinite was more stable. Flotation results showed that higher a kaolinite yield was obtained in the presence of dodecyl dihydroxyethyl methyl ammonium chloride. The calculated results of the solvent-accessible surfaces, the head group charge, and the number of bonds between the collector and the kaolinite show good consistency with the actual flotation results of the three collectors, which can be used as a screening index for kaolinite flotation collectors.Keywords:kaolinite;flotation;collector;adsorption;DFT calculation
研究领域:
化学工程
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材料科学
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表面化学
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Lianjing Mao,Xiaolong Zhou,Tianyu Zheng,Xiao Li,Xiufang Wang,Zhiyu Zhao,Wei Sun,Pengrui Zhang,Jinhe Sun
The metal ion extraction process is usually accompanied by the removal of coordinated water molecules and the change of water content in the extraction phase. However, hierarchical methodologies on water research are incredibly sparse, restricting a thorough knowledge of the extraction mechanism. It was clarified the diversity of water occurrence forms in the extraction phase and quantitative relationship between water, Li + and crown ether based on the (B12C4/B15C5/B18C6-[EMIm][NTf 2 ])-LiNTf 2 solvent extraction system. While the complexation mechanism between hydrated Li + and crown ether was discussed carefully. Firstly, it demonstrated that the water content of the extraction phase: B18C6 > B15C5 > B12C4. Secondly, the water in the extraction phase is mainly collected by solvent and crown ether, with the latter catching water primarily via Li + coordination and weak interactions. In the end, focusing on the water captured by the crown ether through Li + coordination, slope analysis and DFT calculations found that Li (H 2 O) 4 + was removed three water molecules to complex with B12C4 or B15C5, whereas B18C6 tends to remove two water molecules. It is precious for a thorough grasp of the mechanism and procedure of Li + extraction by crown ethers. What’s more, it offers novel strategies for investigating water content and transfer mechanisms in extraction systems.
研究领域:
化学
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材料科学
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理论研究
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Xingyuan Wan,Kaixi Jiang,Ting'an Zhang,Kun Wang,Han Yang,Shengnan Lin
Upgrading copper slag into value-added products provides an untapped opportunity to address arsenic pollution in the environment and promote waste recycling, but the problem of excessive arsenic in products remains a huge engineering challenge. Herein, we employ DFT calculations to explore the dissociation mechanism of AsMA and propose a universal descriptor for screening As removal agents for the first time. The dissociation of AsMA is related to the disturbance of the Mo-As bond by Ba and follows the “Perturbation – Re-stabilization – Dissociation” mechanism. The B Ψ value of Ba is near the minimum value of −0.1058 in the universal descriptors, which renders it potential candidates for As removal agents. As expected, Ba can increase As removal efficiency by approximately 45 % when employing the Si-Ca-Ba alloy compared to other Ca-based alloys. This work offers contributions to the As removal technology for copper slag value-added products while also highlighting the DFT calculations used in guiding engineering practices.
研究领域:
环境科学
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材料科学
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化学工程
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产品关联
DOI
高影响因子
Molecular Catalysis
·
2025
·
IF 4.9
Kai Zhang,Shuwei Chen,Zhaohui Guo,Yingxiong Wang,Yan Qiao
As a renewable resource, the catalytic conversion of xylose has attracted much attention. The epimerization of xylose to lyxose is an important way to obtain the rare sugar lyxose. Current approaches to xylose epimerization encounter several challenges, including the requirement for high temperatures, the use of costly catalysts and a propensity for side reactions that favor the formation of ketoses. CaCl 2 is an environmentally friendly and naturally abundant metal salt that can act as a Lewis acid in catalytic processes. Herein, we demonstrate that CaCl 2 and Et 3 N work synergistically to achieve 68 % lyxose yield under mild conditions. Compared to conventional approaches, which often require harsh conditions or expensive catalysts, our system demonstrates a cost-effective and selective strategy. Moreover, through a combined experimental and computational approach (NMR, isotope tracing and DFT), we provide unprecedented mechanistic insights into the role of calcium complexation in facilitating epimerization. Complexation between xylose and calcium ion was confirmed by NMR titration and Diffusion Ordered NMR Spectroscopy (DOSY-NMR). Isotope experiments further demonstrated that the C1-C2 migration caused the turnover of the hydroxyl group at C2 in the presence of calcium ions. The frontier orbital analysis and deprotonation energy calculation showed that the hydroxyl group at C1 had the lowest deprotonation energy, which initiated the ring-opening process. The DFT calculations reveal that the calcium ions preferentially complex with the hydroxyl groups of xylose, thereby reducing the energy barrier for the C1 proton dissociation and facilitating the epimerization. These findings offer a new perspective on xylose epimerization with Ca-based catalyst.
研究领域:
生物化学
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催化化学
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产品关联
DOI
高影响因子
Scientific Reports
·
2022
·Vol. 12
·期 1
·1-8
·
IF 4.996
Wu Junsheng,Zhao Zhuo,Zhou Yanwen
Tin-based perovskite material is the best choice to replace heavy metal element lead during the last several years. Cs 2 SnI 6 with Sn 4+ is a fascinating optoelectronic material, which is a more air-stable composite cesium tin halide peroxide variant from CsSnI 3 . However, the optoelectronic performance between N and P type of Cs 2 SnI 6 varies considerably. Herein, we synthesized uniform Cs 2 SnI 6 by modified two-step method, which thermal evaporated CsI firstly, and followed annealing in the SnI 4 and I 2 vapor at 150 °C resulted in uniform Cs 2 SnI 6 films. SnF 4 is used as a dopant source to improve the optoelectronic properties of Cs 2 SnI 6 films. Results indicate that good crystallinity was obtained for all films and the doped films underwent a crystalline plane meritocracy transition. The doped films had a flat, non-porous morphology with large grains. The high transmittance of the doped films in the infrared region led to the avoidance of self-generated thermal decomposition. With the help of F − , the films became more conductive and had higher carrier mobility. DFT calculations showed that doping with F reduced the surface energy of (004), resulted in a preferred orientation transition in the crystal of Cs 2 SnI 6 . Fluorine doped double layer perovskite materials would have a broader application prospect.
研究领域:
材料科学
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物理化学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xu Zhang,Shuting Li,Jiyang Zhang,Jihong Liu,Chaoyang Huang,Jiapeng Zhu,Guixiao Jia,Shengli An
CeO 2 is a promising electrolyte for intermediate-temperature solid oxide fuel cells (IT-SOFCs). Studies have found that F-doping improves its ionic conductivity, but the underlying mechanisms remain unclear. Therefore, this study employs a DFT+U method to calculate geometrical and electronic structures and oxygen ion migrations of Gd-, Ca- and F-dopings co-doped CeO 2 . The calculated results are verified by our experiment. DFT calculations find that oxygen vacancies (V) are easily formed at next-neighboring sites near the F - ions, different with the case of Gd- and Ca-doped CeO 2 . Gd-, Ca- and F-dopings strengthen Ce-O bonds, inconstant with the result from the reported experimental hypothesis for the F-doping. The F-doping restrains the change of Ce 4+ to Ce 3+ . Migration energy barriers E m of oxygen ions are mainly affected by the migration distances and peripherally done by the oxygen vacancy cavity size and the defect association. Due to the lager oxygen vacancy cavity size and the smaller defect association in CGOF and CGOCF, the F-dopings have the smaller E m . This is contrary to the speculation of the reported experimental study based on the electronegative comparison of F and O. Our experiment finds that Ca and F co-doping significantly increases the conductivity, 3.9 times of the conductivity of Gd-doped CeO 2 . The study clarifies the nature mechanism of the ionic conductivity in doped CeO 2 , offering atomic-level insights to aid the development of high-performance CeO 2 -based electrolytes.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Tuo Zheng,Haiyan Fan,Jia Zhao,Jile Fu,Songshou Ye,Sajid Ali,Nuowei Zhang,Jinbao Zheng,Binghui Chen
In diesel adsorption desulfurization, the coordination bonding between the adsorbent and sulfur compounds is interfered by aromatic compounds in diesel. Transition metal cation exchanged zeolites Y has exhibits exceptional anti-interference performance. In this work, the influence of electron configuration on coordination bonding is explored, specifically between the adsorbent and substrate, using both experimental and DFT theoretical methods. Initially, NiY, CuY and ZnY were synthesized and evaluated for their desulfurization performance in model solution (sulfur content: 25 ppmw dibenzothiophene [DBT]) with two toluene concentrations (1 w% and 3 w%). It is found that CuY showed the highest performance with retention rate at 70.2 %. Subsequently, DFT calculations revealed the binding energy between Cu(II) and DBT was −2.71 eV, higher than Ni(II) and Zn(II), and that between Cu(II) and toluene was −1.75 eV, lower than Ni(II) and Zn(II), indicating that the highest binding energy difference was responsible for the best adsorption capability. Apart from these, wave function analysis show the electron configuration between Cu(II) and DBT had the highest binding energy difference. Finally, the impact of electron configuration on adsorption performance is further investigated by modulating the electron configuration of Ni(II) to enhance/suppress its adsorption capability. According to the findings of this study, tuning the electron configuration is an effective strategy to develop materials in adsorptive desulfurization particularly for extra low sulfur content.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Wanli Zhang,Meigui Ou,Chunlin Yang
In this paper, erbium-doped gadolinium oxide rare earth oxide nanoparticles (Gd 2 O 3 :Er 3+ ) with good light absorption capacity from the visible to the infrared region were prepared by polyol method, and then compounded with TiO 2 by hydrothermal method. SEM, TEM, XPS, UV–vis and electrochemical workstation were used to study the morphology, structure, UV–vis light absorption and photoelectrochemical (PEC) properties of Gd 2 O 3 :Er 3+ /TiO 2 . The results showed that the Gd 2 O 3 :Er 3+ spherical nanoparticles with a particle size of about 15 nm were uniformly distributed on the surface of the TiO 2 nanorod array, and the Gd 2 O 3 :Er 3+ /TiO 2 nanocomposites had good light absorption capacity in the infrared region. Furthermore, the photocurrent densities of Gd 2 O 3 /TiO 2 and Gd 2 O 3 :Er 3+ /TiO 2 were 2.08 and 2.75 times higher than those of TiO 2 , respectively, manifesting that the broadening of infrared light absorption can improve the PEC property of TiO 2 . Meanwhile, the DFT calculation results showed that the energy band of Gd 2 O 3 :Er 3+ /TiO 2 was significantly narrower than that of TiO 2 , indicating that Gd 2 O 3 :Er 3+ /TiO 2 had a redshift phenomenon of UV–vis absorption. The calculation results of state density showed that the f orbital of Gd 2 O 3 :Er 3+ intersected with the d orbital of TiO 2 , indicating that there is an electron transfer between Gd 2 O 3 :Er 3+ and TiO 2 .
研究领域:
材料科学
·
光催化
·
理论计算
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Xiuqin Dong,Jianhang Tian,Junwei Lei,Yifei Chen
Copper as a non-noble metal catalyst has great prospects in the hydrogenation of acetic acid to ethanol. In this paper, Cu-MnO/SBA-15 catalysts with highly catalytic performance and stability were prepared. The mechanism was elucidated by experiments and DFT calculations . The Cu and MnO were coexistent on reduced x Cu y Mn/SBA-15. Appropriate Cu/Mn ratio was beneficial for increasing the Cu surface area and reducing the size of Cu. The rate-controlled step was found and the MnO could effectively lower the difficulty of acetaldehyde formation by dioxyethylidene. DFT calculations indicated that the formation of ethyl acetate at the Cu-MnO interface was largely prevented. The optimal catalytic hydrogenation activity was obtained for 9Cu1Mn/SBA-15, with the conversion of acetic acid and selectivity of ethanol of 99.9% and 90.1%, respectively. The catalytic activity could remain within 72 h which was more stable than the original Cu-based catalyst.
研究领域:
催化化学
·
理论化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2023
·Vol. 13
·期 7
·1031
·
IF 3.9
Jie Lin,Yihong Ding,Huile Jin,Tianbiao Zeng
Nickel, cobalt, and manganese oxides are easily obtainable non-noble metal catalysts for water splitting. However, the relationship between composition and catalysts’ performance still needs systematic studies. Herein, guided by theoretical calculations, a low overpotential, easily prepared Mn-doped Co3O4was deposited on graphite plates for water splitting. The 30% Mn-doped Co3O4(Co2.1Mn0.9O4) required the lowest overpotential for oxygen evolution reaction (OER), in which the Co2.1Mn0.9O4reached 20, 30, and 50 mA cm−2in the overpotentials of 425, 451, and 487 mV, respectively, with 90% IR compensation. Under overall water-splitting conditions, the current density reached 30 mA cm−2at an overpotential of 0.78 V without IR compensation. Charge density difference analysis illustrates that doped Mn provides electrons for O atoms, and that Mn doping also promotes the electron fluctuation of Co atoms. XPS analysis reveals that Mn-doping increases the chemical valence of the Co atom, and that the doped Mn atom also exhibits higher chemical valence than the Mn of Mn3O4, which is advantageous to boost the form of based-OOH* radical, then decrease the overpotential. Considering the particular simplicity of growing the Co2.1Mn0.9O4on graphite plates, this work is expected to provide a feasible way to develop the high-performance Co-Mn bimetallic oxide for water splitting.Keywords:water splitting;bimetallic oxides;Mn-doped Co3O4;DFT calculation
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
KeXuan Wu,Jing Cao,Ran Zhang,Yong Pei,Ting Peng,Ge Chen
Co 3 O 4 has exhibited chlorine evolution reaction (CER) activity comparable to that of RuO 2 . However, it is plagued by relatively low catalytic activity and insufficient long-term stability. In the field of cobalt oxide doping, typically, a relatively large quantity of dopants is used to modulate its performance. In contrast, the exploration of doping with trace amounts of elements has been scarce. In this study, small amounts of Sn and Bi were introduced into the Co 3 O 4 electrocatalyst. The impacts of different doping ratios on the morphology and catalytic performance of the catalyst were systematically investigated. Under specific proportion conditions, the co-doping of these two elements with cobalt tetroxide demonstrated a remarkable synergistic effect. Moreover, a mechanism for the improvement of catalyst performance, based on DFT calculations, was proposed. Subsequently, the ammonia-nitrogen degradation capacity and long-term stability of the modified catalyst were evaluated through ammonia-nitrogen degradation experiments. The degradation mechanism was further elucidated using free-radical scavenging experiments.
研究领域:
环境科学
·
材料科学
·
电催化
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Ruiqi Zhang,Panpan Hao,Xiujie Cheng,Rana R. Neiber,Ling Wang,Yi Li,Junli Xu,Dongxia Yan,Qing Zhou,Jiayu Xin,Xingmei Lu
Ionic liquids (ILs) have been recognized as environmentally friendly and effective catalysts for poly (ethylene terephthalate) (PET) glycolysis. However, further investigation is required to gain a deeper understanding of the depolymerization mechanism. In this study, a series of experiments are conducted to investigate the impact of metallic and non-metallic ILs, containing diverse anions, on the interaction with PET surfaces. The findings indicate that the catalytic efficiency of IL is strongly correlated to the intensity of the interaction with PET. When the interface adhesion strength is more than twice that of PET/PET, the IL exhibits efficient catalytic properties in PET glycolysis. Therefore, an innovative approach involving the use of AFM for efficiently assessing highly effective IL catalysts is proposed. In addition, attenuated total reflectance Fourier transform-infrared (ATR-FTIR) spectroscopy and density functional theory (DFT) calculations further demonstrate the predominant interaction mechanism between ILs and PET. This research provides guiding significance for understanding the mechanism of PET glycolysis.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 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）