查找使用阿拉丁产品的科研文献

A novel assessment method for the catalytic activity of ionic liquid degradation of PET

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.

Synthesis of vanadium nitride from vanadium spinel by synchronous reduction and nitridation with ammonia energy

Yang You,Qingqing Hu,Fupeng He,Yongjie Liu,Qingyun Huang,Xuyang Liu,Zhixiong You,Xuewei Lv

Summary Ammonia gas (NH 3 ) is a clean energy, as well as an efficient reduction and nitridation agent. A novel process of reduction and nitridation with NH 3 followed by magnetic separation and low-temperature selective chlorination to deal with vanadium slag has been proposed. Vanadium spinel (V-Fe spinel, FeV 2 O 4 ) is the main V-bearing phase in vanadium slag, and its reduction and nitridation behavior with NH 3 were investigated in this study. Thermodynamic analysis indicated that the reaction was feasible. The experimental results demonstrated that NH 3 gas was an excellent reagent for reduction and nitridation. DFT calculation proved that NH 3 molecule was easier adsorbed on V atom. The phase component of the final product was Fe/Fe 4 N/VN x O y , whose relative mass fractions obtained by Rietveld refinement analysis were 23.5%, 1%, and 75.5%, respectively. The evolution of iron and vanadium was in the order FeV 2 O 4 → Fe 4 N/Fe 6 N 2−3 → Fe 4 N/Fe and FeV 2 O 4 → V 2 O 3 → VN x O y , respectively. VN x O y was a solid solution, whose O content decreased gradually as the temperature and duration time increased, whereas the N content increased correspondingly. The O content can be decreased to less than 0.10 wt.% after reduction and nitridation at 800°C to 850°C for 3 h.

Organic acid tailors anhydrous magnesium carbonate: DFT-guided dehydration mechanism and morphology engineering

Yahui Feng,Jiajun Xu,Jie Xu,Li Gao,Bingxin Liu,Chao Zhang,Shiai Xu,Yunhua Lu

Mineral carbonation into Anhydrous Magnesium Carbonate (AMC) is a promising pathway for permanent CO₂ storage, yet the strong hydration of Mg 2+ hinders its precipitation under mild conditions. To overcome this limitation, organic acids ( l -ascorbic acid (LA), citric acid (CA), malic acid (MA), and tartaric acid (TA)) are employed as dual-functional agents: carbon sources and hydration disruptors. Through combined density functional theory (DFT) calculations and experimental validation, it is revealed that organic acids weaken the hydration shell of [Mg(H₂O)₆] 2+ by forming stable coordination bonds with Mg 2+ , significantly reducing the dehydration energy barrier (e.g., ΔG ‡ ₆-₅ decreased from 180.53 kJ/mol in H₂O to 76.71 kJ/mol for LA). Systematic hydrothermal synthesis demonstrates that LA enables high-purity AMC formation at 450 K, the widest temperature window among the tested acids. At the same time, TA requires ≥525 K. Crucially, each acid directs distinct AMC morphologies, hydrangea-like (LA), cubic (CA), layered (MA), and block-like (TA), attributed to site-specific adsorption on crystal surfaces. This work provides a molecular-level blueprint for overcoming the dehydration barrier in AMC synthesis and advances strategies for accelerating sustainable CO₂ mineralization.

Synthesis, photophysical properties and TD-DFT calculation of fluorescent dyes based on pyrenylthiazoles

Tong Dingyi,Duan Haifeng,Wang Jiajun,Zhang Li,Cao Jungang,Wei Zhonglin,Lin Yingjie

Tartaric acid modified nitrogen-doped hydrothermal carbon for germanium recovery and DFT calculation

Yanhong Liu,Lihui Gao,Shulei Li,Wenfeng Pan,Hongzhao Liu,Keyi Xu,Hongyang Mao,Si Shen

The efficient recovery of germanium from complex secondary resources is a significant challenge in resource sustainability. In this study, a tartaric acid-functionalized nitrogen-doped hydrochar (NPB-TA) was synthesized for selective germanium (Ge) capture from aqueous solutions containing other metal ions. Adsorption experiments demonstrated that NPB-TA can be used in germanium solutions of varying pH and concentration, achieving a saturated adsorption capacity of 112.23 mg/g at pH = 3. The adsorption process was found to be in accordance with the Langmuir isotherm and pseudo-second-order kinetic models, indicating monolayer adsorption and chemisorption as the dominant mechanisms. Moreover, NPB-TA exhibited superior selectivity toward Ge (IV) even in binary systems with competing ions. Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Density functional theory calculations were applied to elucidate the adsorption mechanism. The mechanism involves synergistic coordination between Ge (IV) and surface-bound -OH/-COOH groups, with amino groups facilitating the formation of stable chelating rings containing C-O-Ge/C-N-Ge bonds. This study demonstrates that tartaric acid-modified N-doped biosorbent has potential for the selective recovery of germanium from aqueous solution.

Screening of catalysts based on DFT and preparation of high transmittance PET films

Yifei Ding,Wenxun Sun,Hongwei Gao,Ruiyu Zhang,Xiaobin Yang,Yongping Bai,Shuai Sun

High-transmittance polyester films are critical for advanced display technologies, yet the relationship between catalyst design and optical performance remains poorly understood. This work investigates seven metal-based catalysts and develops an economical and efficient composite catalyst accordingly. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies of these catalysts are calculated using density functional theory (DFT) method. Results demonstrate that catalysts with lower LUMO energy levels can significantly promote nucleophilic attack during polycondensation, consequently exhibiting superior catalytic efficiency. Subsequently, we prepare a composite catalyst composed of cobalt(II) acetate tetrahydrate and germanium(IV) oxide. By employing the composite catalyst, the synthesized PET films achieved promising transmittance of 91.43 % and luminosity of 92.82 %. This study provides a DFT-driven strategy for designing optical polyesters, offering a scalable approach for advanced display applications.

Polyphenols-Stabilized Black Titanium-Oxo Cluster: Crystal Structure, DFT Calculations, and Photothermal Conversion

Mei-Yu Xu,Zeng-Ni Xiang,Zhong-Mei Xian,Guang-Ming Liang,Hua-Hong Zou

The controlled synthesis of fully stable titanium-oxo clusters (TOCs) through organic ligands to obtain products with high stability and excellent light-absorption properties remains a major challenge. In this study, we report the syntheses of a polyphenols-stabilized functionalized TOCs via an in situ solvothermal strategy, formulated as [Ti8(IV)(μ3-O)4(μ2-O)2(HTBA)8(H2O)4] (Ti8-a), (H4TBA = 2,3,4-Trihydroxybenzoic acid). Interestingly, Ti8-a exhibits a striking black color, classifying it among black TOCs, and possesses an ultralow optical band gap of 1.3 eV. Owing to the comprehensive shielding by the rich intramolecular supramolecular interactions and polyphenol ligands, Ti8-a exhibits excellent stability across various media and environments, including exposure to air and immersion in different solvents. Therefore, Ti8-a was tested for its photoelectric response performance and photothermal conversion capability because of its extremely low optical band gap and excellent stability. The experimental results show that Ti8-a exhibits excellent photoresponse and photoconversion capabilities. The photothermal conversion efficiency can reach 62.24%, and it can rapidly heat the temperature of N,N-dimethylformamide (DMF) to 88.2 °C.

Interaction mechanism of calcite and four representative organic molecules: Experiments and DFT study

Rukuan Chai,Yuetian Liu,Qianjun Liu,Jing Xin

Calcite crystal-organic molecule interaction governs the wettability formation and alteration of carbonate reservoirs, and influences the oil recovery. However, its in-depth interaction mechanism in atomic scale have not been classified clearly. Regarding this, this study combines the atomic force microscopy (AFM), fourier transform infrared spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) to systemically investigate the adsorption regularities and mechanisms of four representative organic molecules of crude oil on calcite surface. AFM results illustrated that the adsorption amount of the four organic molecules on calcite surface is in the order of benzoic acid>pyridine>thiophene>toluene. FTIR and XPS results explicated that the COOR and OH functional groups are formed in the benzoic acid adsorption; the Ca of calcite surface and N of pyridine are involved in the interaction, and OH functional groups are also formed in pyridine adsorption; only the OH bond is formed in thiophene adsorption, and no bond is formed in toluene adsorption. DFT results verified the experiments results and further revealed the interaction mechanism in atomic scale. Firstly, DFT results showed that the adsorption energies of benzoic acid, pyridine, thiophene and toluene on calcite surface are −1.39 eV, −0.97 eV, −0.49 eV and −0.31 eV, respectively. Secondly, DFT results explicated that the Ca-O ionic bond and H O covalent bond are formed in benzoic acid-calcite interaction; the Ca-N ionic bond and H O hydrogen bond are formed in calcite-pyridine interaction; only the H O hydrogen bond is formed in calcite-thiophene interaction; No chemical bond is formed in calcite-toluene interaction.

Hydrogenation of 2-ethylanthraquinone with bimetallic monolithic catalysts: An experimental and DFT study

Yanyan Guo,Chengna Dai,Zhigang Lei

We studied the hydrogenation of 2-ethylanthraquinone (eAQ) over Pd/SiO 2 /COR (COR = cordierite) monometallic and Pd-M/SiO 2 /COR (M = Ni, Fe, Mn, and Cu) bimetallic monolithic catalysts, which were prepared by the co-impregnation method. Detailed investigations showed that the particle sizes and structures of the Pd-M (M = Ni, Fe, Mn, and Cu) bimetallic monolithic catalysts were greatly affected by the second metal M and the mass ratio of Pd to the second metal M. By virtue of the small particle size and the strong interaction between Pd and Ni of Pd-Ni alloy, Pd-Ni bimetallic monolithic catalysts with the mass ratio of Pd/Ni = 2 achieved the highest H 2 O 2 yield (7.5 g/L) and selectivity (95.3%). Moreover, density functional theory calculations were performed for eAQ adsorption to gain a better mechanistic understanding of the molecule-surface interactions between eAQ and the Pd(1 1 1) or PdM(1 1 1) (M = Ni, Fe, Mn, and Cu) surfaces. It was found that the high activity of the bimetallic Pd-Ni catalyst was a result of strong chemisorption between Pd 3 Ni 1 (1 1 1) and the carbonyl group of eAQ.

Synthesis and DFT studies of novel aryloxymaleimides via nucleophilic substitution of tosyloxy group

Maocai Yan,Zhen Zhang,Jinhui Zhou,Wei Li,Chunyan Zhang,Jingchang Zhang,Huannan Wang,Xuelu Yang,Shuai Fan,Zhaoyong Yang

Maleimide skeleton distributes widely in a great many substances, and maleimides are very useful building blocks in organic synthesis and many related disciplines, like bioconjugation . As an excellent leaving group, tosyloxy (-OTs) group are very popular in organic synthesis; however, reports on use of -OTs group on maleimide scaffold are very rare. In this study, 3-tosyloxymaleimide was prepared from l -tartaric acid and used to react with various phenols or naphthols under PTC condition to give 3-aryloxymaleimides through nucleophilic substitutions. Yields of the reaction were not high due to a competitive transesterification reaction; however, this reaction would be practical if the side-reaction could be suppressed by appropriate reaction conditions. The reaction mechanism was investigated by theoretical computation. The intermediates and transition states of the reaction, as well as the potential barrier and reaction free energy , were calculated using density functional theory (DFT), and influencing factors of the reaction were discussed. Theoretical computations showed that this nucleophilic substitution is favorable both kinetically and thermodynamically, while electron-withdrawing groups on phenols are harmful to such reactions. This study will provide new knowledge and insights on the chemical properties of maleimide and tosyloxy group, as well as the related chemical reactions.

Binding of triclosan and triclocarban to pepsin: DFT, spectroscopic and dynamic simulation studies

Yuanyuan Yue,Zhiyue Wang,Yanyan Zhang,Zhixian Wang,Qingzhang Lv,Jianming Liu

The use of antibacterial agents, triclosan (TCS) and triclocarban (TCC), in personal care products can result in direct human exposure. Density Functional Theory (DFT) was utilized to evaluate the electronic properties of TCS and TCC, and the determined energetically accessible transitions across the HOMO-LUMO gap. Choosing pepsin as a model protein, we explored the binding effects of TCS or TCC on pepsin by molecular docking and dynamic simulations. Titration of pepsin with TCS or TCC at pH 2.2 led to quenching of the pepsin intrinsic fluorescence via formation of a ground-state complex. The binding constants of the TCS/TCC-pepsin complexes, determined at 296 K, were (7.053 ± 0.030) × 10 4  M −1 and (6.233 ± 0.060) × 10 4  M −1 , respectively. Analysis of the thermodynamic properties of each system at various temperatures demonstrated that the binding reaction is a spontaneous process driven by hydrophobic interactions. The spectroscopic results revealed that changes in the secondary structure of pepsin are induced by TCS or TCC. The thermal stability of pepsin was evaluated, and no change in thermal stability was observed upon substrate binding. However, the binding of either TCS or TCC to pepsin effectively reduced the activity.

DFT insights into the selective NH3 sensing mechanism of two dimensional ZnTe monolayer

Xiao Chang,Xiaofang Li,Qingzhong Xue

Exploring novel NH3 sensing materials is crucial in chemical industries, fertilizing plants and medical fields. Herein, for the first time, the NH3 sensing behaviors and sensing mechanisms of two dimensional (2D) ZnTe monolayer are systematically investigated by density functional theory calculations. It is shown that 2D ZnTe monolayer exhibits excellent selective NH3 sensing properties. (220) crystal facet of ZnTe possesses a higher NH3 adsorption energy (−1.59 eV) and a larger charge transfer (0.195e) than (111) and (311) crystal facets. The positive charges could enhance NH3 sensing while the negative charges could reduce NH3 sensing. The NH3 adsorption strengths are significantly improved in O2 atmosphere while it is negligibly affected by N2 atmosphere and H2O atmosphere. Moreover, the presence of Zn vacancy and Fe, Co, Ni doping could improve the NH3 sensing of ZnTe. Additionally, the experimental results confirms that ZnTe possesses a low detection limit of 0.1 ppm NH3. These theoretical predictions and experimental results present a wide range of possibilities for the further development of ZnTe monolayer in NH3 sensing fields.