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Physical Insight for Grafting Polymer Chains onto the Substrate via Computer Simulations:Kinetics and Property

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Chinese Journal of Polymer Science 2022年第7期40卷 817-833页

作者： Chi-Xin Liang Hui Lu Bai-Ying Huang Ji-Yuan Xing feng-long gu Hong Liu School of Chemistry South China Normal UniversityKey Laboratory of Theoretical Chemistry of Environment Ministry of EducationGuangzhou510006China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun130023China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

Molecules adsorbed or attached on a surface is a quite basic phenomenon in numerous chemical or biological ***-onto is considered as a feasible way to achieve *** grafting reaction is essentially controlled by the diffusion of the molecules,thus it is more likely a physical issue,instead of a chemical *** of the experimental difficulty in measuring the properties of surface-attached molecules(e.g.,the polymeric molecules),the surface-bound molecules are often assumed as with the same properties as that of the start feeding ones in *** assumption was even used to guide further characterization,while it is proved to be invalid by different quantifying ***,an effective prediction for the properties of surface-bound molecules is still *** on a microscopic level and a dynamic perspective,the grafting process onto a flat substrate with polydisperse feeding polymeric molecules is investigated in-depth by coarse-grained Brownian dynamics simulation as well as model *** find from simulations that for the final grafting densityσ_(g)and the mean chain length of start feeding molecules,the dependence ofσ_(g)-^(γ)with the constant exponential factorγmay be a determined rule for one-end functionalized flexible linear polymer chains grafting on the flat *** grafting-onto is a multiple interplayed process,our simulation study indicates that there is an optimized initial concentration of start feeding molecules for achieving high grafting density of surface-bound *** also propose a correctional equation to quantitatively predict the molecular weight distribution(MWD)of surface-bound polymeric molecules,which may be effective for predicting the MWD of the surface-bound ones in specific *** simulation study helps to better understand the kinetics of grafting-onto process,and serves as a theoretical guide to achieve the precise design of surface modification materials vi

关键词： Grafting-onto Grafting density Polydisperse Molecular weight distribution

A TDDFT Approach for Calculating Frequency Dependent Polarizabilities and Excitation Energies with Non-Orthogonal Localized Molecular Orbitals

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A TDDFT Approach for Calculating Frequency Dependent Polariz...

The Sequential Reduction and Oxidation Mechanism for TBBPA Degradation under UV/Fenton: The Theoretical Study

第十三届全国量子化学会议

作者： Daoling Peng Liang Peng feng long gu Weitao Yang Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of Chemistry and EnvironmentSouth China Normal University Department of Chemistry Duke University

Time dependent density functional theory（TDDFT） is a useful tool to calculate molecular properties with reasonable computational costs comparing to wave function based ab initio approaches. A linear scaling TDDFT is desired for applications with very large systems. The couple perturbed Hartree-Fock（HF）[1] and TDDFT[2] approach has been reformulated based on non-orthogonal localized molecular orbitals（NOLMOs）[3] to calculate molecular frequency dependent *** NOLMOs are the most localized representation of molecular electronic orbitals, methods based on NOLMOs are potentially ideal for investigating very large systems. The NOLMO based frequency dependent coupled perturbed equations up to third order have been implemented in the PYSCF[4] program and several chemical systems are chosen to verify our approach. As shown in the following figure, we were able to calculate the molecular polarizability dispersion curve using the NOLMO based couple perturbed TDDFT approach. The singular points in the dispersion curve represent the excitation energies. But the excitation energies can be obtained more conveniently using the linear response TDDFT approach through finding the eigenvalues of a kernel matrix. We also implemented the NOLMO base linear response TDDFT method in the PYSCF program to study molecular excited states. This work represents the first step to achieve NOLMO based linear scaling TDDFT approach.

关键词： TDDFT excited states NOLMO linear scaling

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The Sequential Reduction and Oxidation Mechanism for TBBPA D...

Constructing Pr-doped CoOOH catalytic sites for efficient electrooxidation of 5-hydroxymethylfurfural

中国化学会第十二届全国量子化学会议

作者： Xiao Huang Liang Peng Shaopeng Li feng long gu School of Chemistry & Environment South China Normal University

Tetrabromobisphenol A（TBBPA）,a widely used brominated flame retardant,is harmful to human and wildlife in various aspects as an endocrine *** DFT calculations both in gaseous phase and aqueous phase are carried out to investigate the degradation mechanism of *** is found that there exist reductive process with the effect of photoelectron e CB-and oxidative process of·OH radical attacking three possible sites of TBBPA in the whole reactions,which are different from the degradation mechanism proposed by experiment（Water Res.2012,46（15）,4633-4644）.According to our calculations,the debromination process is caused by the reduction by photoelectron e CB-rather than·OH radical attacking C-Br ***,the oxidative process is due to·OH radical attacking three possible sites of TBBPA to form different *** the debromination process,the reduction by photoelectron e CB-is the most crucial step to reductive degradation of TBBPA,and the formation of tri-brobisphenol A radical（IM3）is the dominant step to form the reductive product tri-brobisphenol A（P1）.In the oxidative process,energy barriers both in gaseous and aqueous phase are very close for abstracting hydrogen atom reaction,addition reaction,and substitution reaction of the first step,and it demonstrates that these three different reactions are *** contrast,abstracting hydrogen atom by·OH radical is the most plausible reaction for forming 2,2-bis（3,5-dibromo-4-hydroxyphenyl）propane radical（IM4）,while forming 4-isopropylene-2,6-dibromophenol（P2）and 3,5-dibromophenol radical（IM5）may be difficult to occur because of high energy ***,compared to abstracting hydrogen atom reaction,the addition reaction of the second step is more likely to take place.

关键词：

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Journal of Energy Chemistry 2025年第1期100卷 234-244页

作者： Botao Fan Hao Zhang Bang gu feng Qiu Qiue Cao Wenhao Fang School of Chemical Science and Technology Yunnan UniversityKunming 650091YunnanChina National Center for International Research on Photoelectric and Energy Materials School of Materials and EnergyYunnan UniversityKunming 650091YunnanChina

Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current ***,a Pr-doped Co(OH)_(2)hexagonal sheet(Pr/Co=1/9,in mole)is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural(HMF)oxidation reaction(HMFOR)to produce 2,5-furandicarboxylic acid(FDCA).This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V(***)and requires only 1.10 V(***)to reach a current density of 10 mA cm^(-2)for HMFOR,significantly outperforming Co(OH)_(2)benchmark(i.e.,210 mV higher to reach10 m A cm^(-2)).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical *** unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward *** can be one of the most outstanding results for Co-based HMFOR catalysts to date in the *** this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.

关键词： Biomass conversion Electrocatalysis 2,5-Furandicarboxylic acid Doped Co catalyst Co3+active sites Charge transfer rate

Impact of temperature and salinity on fines detachment: AFM measurements and XDLVO theory

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Petroleum Science 2025年第1期22卷 338-347页

作者： Wei-feng Yuan Yu-long Yang Lu Yuan Ji-Rui Hou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum Unconventional Petroleum Research Institute China University of Petroleum

Fine particle detachment and subsequent migration can lead to severe pore plugging and consequent permeability decline. Therefore, it is crucial to quantify the critical condition when fine particle detachment occurs. The frequently observed deviations or even contradictions between experimental results and theoretical predictions of fines detachment arise from an insufficient understanding of adhesion force that can be highly influenced by salinity and temperature. To clarify the intrinsic influence of salinity and temperature on fines detachment, adhesion forces between carboxyl microspheres and hydrophilic silica substrates in an aqueous medium were measured at various salinities and temperatures using atomic force microscopy(AFM). The AFM-measured adhesion force decreases with increasing salinity or temperature. Trends of mean measured adhesion forces with temperature and salinity were compared with the DLVO and XDLVO theories. DLVO theory captured the trend with temperature via the impact of temperature on electric double layer interactions, whereas XDLVO theory captured the observed trend with salinity via the impact of salinity on the repulsive hydration force. Our results highlight the significance of hydration force in accurately predicting the fate of fines in porous media.

关键词： Adhesion force AFM Temperature Salinity XDLVO Hydration force

Diazo Esters as Dienophiles in Intramolecular（4+2） Cycloadditions: Computational Explorations of Mechanism

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Diazo Esters as Dienophiles in Intramolecular（4+2） Cycload...

Zincophilic and hydrophobic bifunctional PFA-COOH-CNT artificial SEI film for highly stable Zn anode

第十三届全国量子化学会议

作者： Abing Duan Peiyuan Yu Fang Liu feng long gu K.N.Houk Key Laboratory of Theoretical Chemistry of Environment Ministry of Education School of Chemistry and EnvironmentSouth China Normal University Department of Chemistry and Biochemistry University of California

The first experimental examples of Diels–Alder（DA）reactions of diazo compounds as heterodienophiles with dienes have been studied with density functional theory（DFT） using the M06-2X functional. For comparison, the reactivities of diazo esters as dienophiles or 1,3-dipoles with 1,3-dienes in intermolecular model systems have been analyzed by the distortion/interaction（D/I） model. The 1,3-dipolar cycloaddition is strongly favored for the intermolecular system. The intramolecular example is unique because the tether strongly favors the（4+2） cycloaddition.

关键词： DA 1,3-Dipolar DFT Diazo esters Diene D/I

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Nano Research 2025年第2期18卷 346-357页

作者： Lingyao Kuang Bohui Xu long Zhang Zheshuai Lin Xingxing gu Xiaolei Ren Yanglong Hou Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and ResourcesChongqing 400067China Functional Crystals Lab Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China School of Materials Shenzhen Campus of Sun Yat-Sen UniversityShenzhen 518107China Beijing Key Laboratory for Magnetoelectric Materials and Devices(BKL-MMD) School of Materials Science and EngineeringPeking UniversityBeijing 100871China

Aqueous zinc-ion batteries(AZIBs)are regarded as one of the most promising rivals in the upcoming high-energy secondary battery market because of their safety and ***,the zinc dendrites growth and hydrogen evolution corrosion of the Zn anode have seriously restricted the application of ***,to overcome these constraints,a three-dimensional(3D)porous PFA-COOH-CNT artificial solid electrolyte interface(SEl)film with high hydrophobic and zincophilic properties was constructed on Zn anode surface by in-situ polymerization of furfuryl alcohol(FA)and carboxyl carbon nanotubes(COOH-CNT).A series of in-situ,ex-situ characterizations as well as the density functional theory(DFT)calculations reveal that the formed PFA-COOH-CNT SEI film with an abundant oxygen-containing group can provide abundant zincophilic sites and induce homogeneous deposition of Zn^(2+),as well as the hydrophobic alkyl and carbon skeleton in PFA-COOH-CNT SEI film can isolate the direct contact of H_(2)O with Zn anode,and inhibit the occurrence of hydrogen evolution reaction(HER).Accordingly,the Zn anode with PFA-COOH-CNT layer can attain an ultra-long cycle life of 2200 h at 1 mA·cm^(-2),1 mAh·cm^(-2).Simultaneously,the assembled PFA-COOH-CNT@ZnllV2Os full cell can also achieve a high reversible capacity of up to 150.2 mAh•g^(-1) at 1 A·g^(-1) after 400 cycles,with a high average coulombic efficiency(CE)of 98.8%.The designed PFA-COOH-CNT artificial SEI film provides a broad prospect for highly stable zinc anode,and can also be extended to other energy storage systems based on metal anodes.

关键词： Zn anode PFA-COOH-CNT solid electrolyte interface(SEI)film zincophilic hydrophobic

Accumulation characteristics and fate modeling of phthalic acid esters in surface water from the Three Gorges Reservoir area,China

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Journal of Environmental Sciences 2025年第3期149卷 46-56页

作者： Shuai Sun Bing Zhang Junjie Hu Wen gu ZhenWang Deling Fan feng Ge Lili Shi LeiWang Nanjing Institute of Environmental Science Ministry of Ecology and Environment of the People’s Republic of ChinaNanjing 210042China Key Laboratory of Pesticide Environmental Assessment and Pollution Control Ministry of Ecology and Environment of the People’s Republic of ChinaNanjing 210042China Solid Waste and Chemicals Management Center Ministry of Ecology and Environment of the People’s Republic of ChinaBeijing 100029China

Phthalic acid esters(PAEs)are a group of compounds widespread in the *** investigate the occurrence and accumulation characteristics of PAEs,surface water samples were collected from the Three Gorges Reservoir area,*** total concentrations of∑_(11)analyzed PAEs(11PAEs)in the collected water samples ranging from 197.7 to 1,409.3 ng/L(mean±IQR:583.1±308.4 ng/L).While DEHP was the most frequently detected PAE,DnBP and DnNP were the most predominant PAEs in the analyzed water samples with a mean contribution of 63.3%of the∑_(11)*** concentrations of the∑_(11)PAEs in the water samples from the upper reaches of the Yangtze River were significantly higher than those from themiddle *** better understand the transport and fate of the PAEs,seven detected PAEs were modeled by Quantitative Water Air Sediment Interaction(QWASI).The simulated and measured values were close for most PAEs,and differences are within one order of magnitude even for the worst *** all simulated PAEs,water and particle inflow were main sources in the reservoir,whereas water outflow and degradation in water were important removal *** contribution ratios of different sources/losses varied fromPAEs,depending on their *** calculated risk quotients of DnNP in the Three Gorges Reservoir area whether based onmonitoring or simulating results were all far exceeded the safety threshold value,implying the occurrence of this PAE compound may cause potential adverse effects for the aquatic ecology of the Three Gorges Reservoir area.

关键词： Phthalic esters Surface water Transport and fate Three Gorges Reservoir area Risk assessment

CoPSe nanoparticles confined in nitrogen-doped dual carbon network towards high-performance lithium/potassium ion batteries

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Chinese Chemical Letters 2025年第1期36卷 568-573页

作者： Zhong-Hui Sun Yu-Qi Zhang Zhen-Yi gu Dong-Yang Qu Hong-Yu guan Xing-long Wu guangdong Engineering Technology Research Center for Photoelectric Sensing Materials and Devices c/o School of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou 510006China MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China

The metal ion batteries have gained widespread attention for wearable electronics due to their competitive energy density and long cycling *** the advanced anode materials is significant for next generation energy storage ***,severe electrode volume changes and sluggish redox kinetics are the critical problems for lithium/potassium ion batteries(LIBs/PIBs)towards large-scale ***,we prepare a novel anode material,which consists of reduced graphene oxide wrapping one-dimensional(1D)N-doped porous carbon nanotube with cobalt phosphoselenide(CoPSe)nanoparticles embedded inside them(r GO@Co PSe/NC).Benefited from the dual carbon decorations and ultrafine nanoparticles structure,it achieves a reversible capacity of 245 mAh/g at 5 A/g after 2000 cycles for LIBs and 215 mAh/g at 1 A/g after 500 cycles for *** pseudocapacitance and GITT measurements are used to investigate the electrochemical kinetics of r GO@Co PSe/NC for *** addition,the lithium ion full cell also shows good electrochemical performance when paired with high capacity LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) *** work provides a feasible electrode design strategy for high-efficiency metal ion batteries based on multidimensional nanoarchitecture engineering and composition tailoring.

关键词： Cobalt phosphoselenide Lithium-ion batteries Potassium-ion batteries Reduced graphene oxide Structural stability Full cell