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Journal of Environmental Sciences 2017年第7期29卷 85-92页

作者： Shaheen Shah ce hao State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China Department of Chemistry Karakorum International UniversityGilgit-Baitistan 15100Pakistan

Sulfamethoxypyridazine（SMP） is one of the commonly used sulfonamide antibiotics（SAs）.SAs are mainly studied to undergo triplet-sensitized photodegradation in water under natural sunlight with other coexisting aquatic environmental organic *** this work,SMP was selected as a representative of *** studied the mechanisms of triplet-sensitized photodegradation of SMP and the influence of selected dissolved inorganic matter,i.e.,anions（Br^-,Cl^-,and NO^-_3） and cations ions（Ca^（2＋）,Mg^（2＋）,and Zn^（2＋）） on SMP photodegradation mechanism by quantum chemical *** addition,the degradation mechanisms of SMP by hydroxyl radical（OH·） were also *** creation of SO_2 extrusion product was accessed with two different energy pathways（pathway-1 and pathway-2） by following two steps（step-I and step-II） in the tripletsensitized photodegradation of *** to low activation energy,the pathway-1 was considered as the main pathway to obtain SO_2 extrusion ***-II of pathway-1 was measured to be the rate-limiting step（RLS） of SMP photodegradation mechanism and the effect of the selected anions and cations was estimated for this *** selected anions and cations promoted photodegradation of SMP by dropping the activation energy of *** estimated low activation energies of different degradation pathways of SMP with OH·radical indicate that OH·radical is a very powerful oxidizing agent for SMP degradation via attack through benzene derivative and pyridazine derivative ring.

关键词： Sulfamethoxypyridazine Photodegradation mechanism Dissolved inorganic matter Hydroxyl radical DFT

Adsorption and Vibration of O on the Pt Stepped Surfaces

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Chinese Journal of Structural Chemistry 2005年第8期24卷 965-972页

作者： DONG Chen-Chu DIAO Zhao-Yu WANG Ze-Xin hao ce Department of Chemistry Shandong Normal University Jinan Shandong 250014 China School of Chemical Engineering Dalian University of Technology Dalian Liaoning 116024 China Department of Chemistry Binzhou University Binzhou Shandong 256600 China

The 5-parameter Morse potential （5-MP） of interaction between an adatom and metal surface cluster is put forward and performed on O-Pt stepped surface systems. We have primarily studied O/Pt（331）, O/Pt（221） and O/Pt（553） systems and drawn some conclusions from the calculated results in good agreement with experimental and theoretical information. The O atom adsorbs stably near the step, so the step is the active place in the reaction. There are two types of atomic states, β1 and β2, in the adsorbed systems, corresponding to the three-fold states and four-fold long-bridged state behind the step respectively. Moreover, the length of （Ⅲ） terrace affects weakly the properties of all critical points in these systems.

关键词： O-Pt system 5-MP adsorption vibration stepped surfaces

Multiple active components synergistically driven heteroatom-doped porous carbon as high-performance counter electrode in dye-sensitized solar cells

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Journal of Energy Chemistry 2019年第4期28卷 89-94页

作者： Hongyu Jing Danyang Wu Suxia Liang Xuedan Song Yonglin An ce hao Yantao Shi State Key Laboratory of Fine Chemicals Dalian University of Technology

A facile template-free in situ self-activation approach for the multiple active components synergistically driven porous carbon was presented via a feasible annealing *** biomass-derived carbon without additional activation reagents was fabricated using K-rich pomelo peel(PP)as the carbon source,which possesses a high electric conductivity where abundant functional hetero-metal atoms are doped into the carbon framework that playing the role of catalytic *** K^+that exists within the biomass can induce self-activation during pyrolysis apart from the activating gases during the pyrolysis *** resulting electrocatalyst of PP-850(PP was pyrolyzed at 850°C in an N_2atmosphere)with abundant heteroatoms possesses a higher power conversion efficiency(Pce)of 7.81%as the counter electrode(ce)of dye-sensitized solar cells(DSCs)compared with the ces calcinated at other temperatures and a similar Pce with Pt counterpart(8.24%)based on the liquid I_3^-/I^-*** better electrocatalytic performance is attributed to the synergistic effect between self-activation and the co-doping of nitrogen,sulfur and phosphorus all together in a carbon *** to the feasibility of large-scale production,rich heteroatom doping,the PP-derived carbon,which simplifies the procedure and decreases the cost,has a potential application for an alternative electrocatalyst for high-performance photovoltaic devices.

关键词： Counter electrode Self-activation Biomass-derived carbon Electrocatalytic performance

Selective Insertion in Copolymerization of Ethylene and Styrene Catalyzed by Half-Titanocene System Bearing Ketimide Ligand： A Theoretical Study

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Chinese Journal of Chemistry 2017年第11期35卷 1731-1738页

作者： Xiaowei Xu Gaohong He Ning-Ning Wei ce hao Yu Pan State Key Laboratory of Fine Chemicals School of Petroleum and Chemical Engineering Dalian University of Technology Panjin Liaoning 124221 China School of Life Science and Medicine Dalian University of Technology Panjin Liaoning 124221 China

The copolymerization of ethylene and styrene can be efficiently carried out by using Cp＊TiCl2（N=CtBu2）/ MAO （Cp＊=η5-C5Me5） system, yielding the poly（ethylene-co-styrene）s with isolated styrene units. In order to in- vestigate the reasons for formation of the structure, the mechanism of copolymerization, especially the selective in- sertion of ethylene and styrene, is studied in detail by density functional theory （DFT） method. At the initiation stage, insertion of ethylene is kinetically more favorable than insertion of styrene, and insertion of styrene kinet- ically and thermodynamically prefers 2,1-insertion. That is different from the conventional half-titanocene system, in which the 1,2-insertion is favorable. At chain propagation stage, the computational results suggest that the con- tinuous insertion of styrene is hard to occur at room temperature due to the high free energy barriers （28.90 and 35.04 kcal/mol for 1,2-insertion, and 29.15 and 34.00 kcal/mol for 2,1-insertion） and thermodynamically unfavora- ble factors in two different conditions. That is mainly attributed to the steric hindrance between the coming styrene and chain-end styrene or ketimide ligand. The computational results are in good agreement with the experimental data.

关键词： polymerization mechanism density functional theory (DFT) half-tianocene copolymerization selec-tive insertion

Simulation and experimental analysis of melt pool evolution in laser engineered net shaping

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Theoretical & Applied Mechanics Letters 2022年第5期12卷 332-340页

作者： Zhuangzhuang Mao Wei Feng ce hao Zhanwei Liu School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China AECC Commercial Aircraft Engine Co.Ltd. Shanghai 200241China

In this work,the evolution of melt pool under single-point and single-line printing in the laser engineered net shaping(LENS)process is ***,the basic structure of the melt pool model of the LENS process is established and the necessary assumptions are ***,the establishment process of the multi-physical field model of the melt pool is introduced in *** is concluded that the simulation model results are highly consistent with the online measurement experiment results in terms of melt pool profile,space temperature gradient,and time temperature ***,some parameters,such as the 3D morphology and surface fluid field of the melt pool,which are not obtained in the online measurement experiment,are ***,the influence of changing the scanning speed on the profile,peak temperature,and temperature gradient of the single-line melt pool is also analyzed,and the following conclusions are obtained:With the increase in scanning speed,the profile of the melt pool gradually becomes slender;The relationship between peak temperature and scanning speed is approximately linear in a certain speed range;The space temperature gradient at the tail of the melt pool under different scanning speeds hardly changes with the scanning speed,and the time temperature gradient at the tail of the melt pool is in direct proportion to the scanning speed.

关键词： Additive manufacturing Laser engineered net shaping Melt pool evolution Simulation analysis Temperature measurement

Insight into the CO2 photoreduction mechanism over 9-hydroxyphenal-1-one(HPHN) carbon quantum dots

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Journal of Energy Chemistry 2021年第1期30卷 269-276,I0009页

作者： Zhengyan Zhao Heming Zhang Xuedan Song Yantao Shi Duanhui Si Hongjiang Li ce hao State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Converting CO2 to carbon-containing fuels is an effective approach to relieving energy *** quantum dots(CQDs) have shown distinct properties and attracted tremendous interest in CO2 ***,we report a joint experimental-computational mechanistic study of photoreduction CO2 to CO on the model catalyst 9-hydroxyphenal-1-one(HPHN) CQDs with known *** theoretical calculations reveal that the rate-determining step is COOH·formation,which is closely related to the proton and electron transfer induced by hydrogen bonding in the excited *** to the calculated volcano plot,the solution we proposed is addition Zn^(2+) *** active center changed from the hydroxyl oxygen atom to the Zn atom and the barrier of the COOH·formation step is noticeably decreased when Zn^(2+) ions are *** is further confirmed by the experimental data that the activity of CO2 reduction increases 2.9 times when Zn^(2+) ions are added.

关键词： CO2 reduction DFT study Reaction mechanism Hydrogen bonding Excited state

Polyaniline-based electrocatalysts through emulsion polymerization:Electrochemical and electrocatalytic performances

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Journal of Energy Chemistry 2017年第1期26卷 182-192页

作者： Shehnaz Xuedan Song Suzhen Ren Ying Yang Yanan Guo Hongyu Jing Qing Mao ce hao State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024LiaoningChina College of Chemical Engineering Dalian University of TechnologyDalian 116024LiaoningChina

One of the major challenges associated with fuel cells is the design of highly efficient electrocatalysts to reduce the high overpotential of the oxygen reduction reaction (ORR). Here we report Polyaniline (PANI) based micro/nanomaterials with or without transition metals, prepared by the emulsion polymerization and subsequent heat treatment. PANI microspheres with the diameter of about 0.7 mu m have been prepared in basic (NH3 solution) condition, using two different types of surfactant (CTAB, SDS) as the stabilizer, ammonium persulphate (APS) as oxidant with aniline/surfactants molar ratio at 1/1 under the hydrothermal treatment. PANI nanorods, Fe-PANI, and Fe-Co-PANI have been synthesized in acidic (HCI) medium with aniline/surfactants molar ratio at 1/2 and polymerization carried out without stirring for 24 h. Products mainly Fe-Co-PANI have shown high current density with increasing sweep rate and excellent specific capacitance 1753 F/g at the scan rate of 1 mV/s. Additionally, it has shown high thermal stability by thermogravimetric analysis (TGA). Fe-PANI has been investigated for excellent performance toward ORR with four electron selectivity in the basic electrolyte. The PANI-based catalysts from emulsion polymerization demonstrate that the method is valuable for making non-precious metal heterogeneous electrocatalysts for ORR or energy storage and conversion technology. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

关键词： Emulsion polymerization Interfacial conductivity Fe-Co-PANI Non-precious metal electrocatalyst Oxygen reduction reaction

New insight into the ultra-long lifetime of excitons in organic-inorganic perovskite： Reverse intersystem crossing

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Journal of Energy Chemistry 2018年第5期27卷 1496-1500页

作者： Guanghao Meng Yantao Shi Xiangyuan Wang Wei Wang Shufeng Wang Min Ji ce hao State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 Liaoning China State Key Laboratory of Fine Chemicals Dalian University of Technology Panjin 124221 Liaoning. China State Key Laboratory for Artificial Microstructure and Mesoscopic Physics Department of Physics Peking University Beijing 100871 China

Recently, an effective exciton diffusion length L exceeding 100μm has been reported for organic- inorganic halide perovskites owing to both the high mobility and ultra-long lifetime of the excitons; however, the origin of ultra-long L is still unclear in nature. In some photoelectric materials, reverse intersystem crossing （RISC） from the triplet to the singlet state can enhance the quantum yield of pho- toluminescence greatly. In this study, our theoretical investigation indicated that the energy difference △E_st between the singlet state and the triplet state of CH_3NH_3Pbl_3 was less than 0.1 eV, which represents one crucial prerequisite for the occurrence of RISC. Meanwhile, the experimental results showed that the photoluminescence lifetime increased with the increasing temperature, a typical feature of RISC. Based on this study, we put forward the hypothesis that the ultra-long lifetime of excitons in organic-inorganic halide perovskite might be caused by the RISC process. This may provide a new insight into the important photophysical properties of such novel photovoltaic materials.

关键词： Inorganic-organic halide perovskite Photophysics Photoluminescence Reverse intersystem crossing Ultra-long lifetime

Carrier dynamics in CsPbI_3 perovskite microcrystals synthesized in solution phase

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Chinese Chemical Letters 2018年第5期29卷 699-702页

作者： Jinwen Hu Chunyi Zhao Sheng He Wenming Tian ce hao Shengye Jin State Key Laboratory of Fine Chemicals Dalian University of Technology State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences

All-inorganic cesium lead halide perovskites （CsPbX3, X=CF, Br-, I-） could provide comparableoptoelectronic properties as a promising class of materials for photovoltaic cell （PV）, photodetector andlight-emitting diode （LED） with enhanced thermal and moisture stabilities compared to organic-inorganic lead halide species. However, fabrication of CsPbI3 perovskite via facile solution process hasbeen difficult due to instability of CsPbl3 in the perovskite cubic phase in ambient air. Herein, we reportthe synthesis of CsPbl3 perovskite microcrystals by low-temperature, catalyst-free, solution-phasemethod. By applying the time-resolve spectroscopic technique, we determine the carrier diffusioncoefficient of 0.6-1.2 cm2/s, the intrinsic carrier lifetimes of 200-1300 ns and diffusion length of4-10 μm in different individual CsPbl3 perovskite microcrystals. Our results suggest the CsPbl3 perovskitemicrocrystals synthesized by solution process exhibit high quality feature and are suitable forapplications in optoelectronic devices.

关键词： Carrier dynamics CsPbl3 Solution process Perovskite

Tuned single atom coordination structures mediated by polarization force and sulfur anions for photovoltaics

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Nano Research 2021年第11期14卷 4025-4032页

作者： Hongyu Jing Zhengyan Zhao Chunyang Zhang Wei Liu Danyang Wu Chao Zhu ce hao Jiangwei Zhang Yantao Shi State Key Laboratory of Fine Chemicals Department of ChemistrySchool of Chemical EngineeringDalian University of TechnologyDalian116024China Department of Chemistry Tsinghua UniversityBeijing100084China SEU-FEI Nano-Pico center Key Laboratory of MEMS of Ministry of EducationCollaborative Innovation Center for Micro/Nano FabricationDevice and SystemSoutheast UniversityNanjing210096China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China

Impeding high temperature sintering is challengeable for synthesis of carbon-supported single-atom catalysts (C-SACs), which requires high-cost precursor and strictly-controlled procedures. Herein, by virtue of the ultrastrong polarity of salt melts, sintering of metal atoms is effectively suppressed. Meanwhile, doping with inorganic sulfur anions not only produces sufficient anchoring sites to achieve high loading of atomically dispersed Co up to 13.85 wt.%, but also enables their electronic and geometric structures to be well tuned. When served as a cathode catalyst in dye-sensitized solar cells, the C-SAC with Co-N4-S2 moieties exhibits high activity towards the iodide reduction reaction (IRR), achieving a higher power conversion efficiency than that of conventional Pt counterpart. Density function theory (DFT) calculations revealed that the superior IRR activity was ascribed to the unique structure of Co-N4-S2 moieties with lower reaction barriers and moderate binding energy of iodine on the Co center, which was beneficial to I2 dissociation.

关键词： inorganic sulfur ions coordination structure regulating anti-sintering dye-sensitized solar cells