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Nano Research 2024年第6期17卷 4961-4970页

作者： Yongpan Gu Yike Li Haoqiang Feng Yanan Han Zhongjun Li College of Chemistry Zhengzhou UniversityZhengzhou 450001China

S-scheme possesses superior redox capabilities compared with the II-scheme,providing an effective method to solve the innate defects of g-C_(3)N_(4)(CN).In this study,S-doped g-C_(3)N_(4)/g-C_(3)N_(4)(SCN-tm/CN)S-scheme homojunction was constructed by rationally integrating morphology control with interfacial engineering to enhance the photocatalytic hydrogen evolution performance.In-situ Kelvin probe force microscopy(KPFM)confirms the transport of photo-generated electrons from CN to SCN.Density functional theory(DFT)calculations reveal that the generation of a built-in electric field between SCN and CN enables the carrier separation to be more efficient and effective.Femtosecond transient absorption spectrum(fs-TAS)indicates prolonged lifetimes of SCN-tm/CN_(3)(τ1:9.7,τ2:110,andτ3:1343.5 ps)in comparison to those of CN(τ1:4.86,τ2:55.2,andτ3:927 ps),signifying that the construction of homojunction promotes the separation and transport of electron hole pairs,thus favoring the photocatalytic process.Under visible light irradiation,the optimized SCN-tm/CN_(3)exhibits excellent photocatalytic activity with the hydrogen evolution rate of 5407.3μmol·g^(−1)·h^(−1),which is 20.4 times higher than that of CN(265.7μmol·g^(−1)·h^(−1)).Moreover,the homojunction also displays an apparent quantum efficiency of 26.8%at 435 nm as well as ultra-long and ultra-stable cycle ability.This work offers a new strategy to construct highly efficient photocatalysts based on the metal-free conjugated polymeric CN for realizing solar energy conversion.

关键词： homojunction built-in electric field morphology control interfacial engineering carrier separation

morphology control of magnetic properties in cobalt nanowires

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Rare Metals 2023年第6期42卷 1994-1999页

作者： Huan-Huan Xu Qiong Wu Ming Yue Cheng-Lin Li Hong-Jian Li College of Materials Science and Engineering Beijing University of TechnologyBeijing100124China

Cobalt nanowires with different shapes and sizes were synthesized by reduction of carboxylate salts of Co^(Ⅱ) in 1,2-butanediol using a solvothermal chemical process.The well-crystallized Co nanowires with hexagonal closepacked(hep) phase are observed and the(002) crystalline direction is along the long axis of nano wires.The morphology control is strongly dependent on the reaction parameters.By varying the amount of capping agent in proper ranges,the effect of reaction parameters on controlling the size and shape of Co nanowires is demonstrated.With the amount of capping agent increasing,the aspect ratio of Co nanowires increases remarkably.However,the magnetic measurement of cobalt nanowires shows that the coercivity of the Co nanocrystals does not increase with the increase in aspect ratio monotonously,which suggests that the tip shape and micros tructure also play an important role in the magnetization reversal process of the Co nanocrystals,and the aspect ratio plays a much less role as the ratio value exceeds 11.To further understand the effect of size on the magnetic properties in the Co nanowires,micromagnetic simulations were performed,which confirms that the magnetic properties are barely affected by the aspect ratio larger than 10.The highest coercivity of624 kA·m^(-1) is obtained for ellipsoid nano wires with a mean length of 200 nm,which also displays a strong magnetic anisotropy.As a result,the highest energy product of the wires reaches 248 kJ·m^(-3).

关键词： Co nanowires morphology control Tip shape High energy product

morphology control of SrCO_3 Crystals using Complexons as Modifiers in the Ethanol-water mixtures

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Chinese Journal of Structural Chemistry 2008年第10期27卷 1223-1229页

作者：张明轩霍冀川于永生崔彩萍雷永林 Institute of Applied Chemistry Southwest University of Science and Technology College of Chemistry and Chemical Engineering Xinyang Normal University

Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlapping plate-like, hexagonal star-like, dumbbell-like, etc. can be synthesized in the ethanol-water mixtures. The samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and Fourier transform infrared spectrograph （FT-IR）. The interrelated effect mechanism is presented in the end. Results show that the modifier carboxyl groups play a significant role in controlling the SrCO3 crystal morphologies, which can alter the crystal growth unit （Sr^2＋） supply mode and induce the crystal formation with the morphologies matching their spatial configurations.

关键词： SrCO3 complexon modifier morphology control ethanol-water mixtures

morphology control of ultrafine cuprous oxide powder and its growth mechanism

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Transactions of Nonferrous Metals Society of China 2010年第S1期20卷 216-220页

作者：曹艳王岳俊周康根毕贞 School of Metallurgical Science and Engineering Central South University

Four shapes of Cu2O particles as sphere,cube,truncated octahedron and octahedron were prepared via glucose reduction of Cu(Ⅱ)under alkaline condition.The products were characterized by XRD and SEM.The effects of the precursor(CuO,Cu(OH)2), reaction temperature and glucose concentration on morphology of Cu2O particles were investigated,and the mechanism of morphology control was discussed on the basic theory of crystal nucleation and growth.It is found that the Cu+supersaturation is remarkably influenced by the precursor kind,reaction temperature and glucose concentration,and the morphology of Cu2O particles can be controlled by the Cu+supersaturation.

关键词： cuprous oxide morphology control supersaturation growth mechanism

A case study of comparing two dimerized acceptor molecules built by different branch-connected and terminal-connected approaches

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Science China Chemistry 2024年第5期67卷 1687-1696页

作者： Kangqiao Ma Huazhe Liang Yuxin Wang Tengfei He Tainan Duan Xiaodong Si Wendi Shi Guankui Long Xiangjian Cao Zhaoyang Yao Xiangjian Wan Chenxi Li Bin Kan Yongsheng Chen State Key Laboratory and Institute of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterThe Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer MaterialsInstitute of Polymer ChemistryRenewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071China School of Materials Science and Engineering National Institute for Advanced MaterialsRenewable Energy Conversion and Storage Center(RECAST)Nankai UniversityTianjin 300350China Chongqing Institute of Green and Intelligent Technology Chongqing SchoolUniversity of Chinese Academy of Sciences(UCAS Chongqing)Chinese Academy of SciencesChongqing 400015China

Dimerized small-molecule acceptors(SMAs) built by the conventional connection of terminal groups of monomers have contributed to exciting long-term stabilities of organic solar cells(OSCs). However, device efficiencies, especially fill factors(FFs), still need to be improved. This probably originates from unsymmetrical molecular structure/conformation-determined less compact/ordered molecular stackings, such as ineffective stackings of constraint terminals. Herein, an exotic dimerized SMA of BC-Th is established by bridging the branched groups(BC-type, branch coupling) of two monomers rather than conventional terminal units(TC-type, terminal coupling). Benefiting from the three-dimensional conformation and more uncurbed terminals,BC-Th exhibits multiple molecular orientations along with a larger dielectric constant and electron mobility compared with TCTh. Finally, an efficiency of 17.43% is achieved by BC-Th-based OSCs, along with the highest FF of 79.13% among all dimerized SMAs-based OSCs to date. When introducing L8-BO as the third component, overall enhanced efficiency of 18.05%and FF of 80.11% are further afforded. Contrarily, TC-Th-based OSCs exhibit much inferior PCE of 16.29% and FF of 74.81%,demonstrating the great advantages of “branch coupling” over “terminal coupling” when building dimerized SMAs.

关键词： organic solar cells dimerized acceptor molecules branch coupling morphology control stability

Manipulating Film Formation Kinetics Enables Organic Photovoltaic Cells with 19.5%Efficiency

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CCS Chemistry 2024年第1期6卷 218-229页

作者： Jianqiu Wang Pengqing Bi Yafei Wang Zhong Zheng Zhihao Chen Jiawei Qiao Wenxuan Wang Jiayao Li Cunbin An Shaoqing Zhang Xiaotao Hao Jianhui Hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049 School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing 100083 School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100

Organic photovoltaic(OPV)cells have demonstrated remarkable performance in small,spin-coated areas.Nevertheless significant challenges persist in the form of large efficiency losses due to the fact that the ideal morphology cannot be preserved in the transition of small-area cells to large-scale panels.Herein,the ternary strategy of incorporating the third component FTCC-Br into the active layer of PB2:BTP-eC9 is employed to improve absorption response,optimize morphology,and reduce charge recombination,leading to a power conversion efficiency(PCE)of 19.5%(certified as 19.1%by the National Institute of Metrology,China).Moreover,the addition of FTCC-Br can control the aggregation kinetics of the active layer during the film formation process,transferring the optimal morphology to the blade-coated large-area films.Based on the highly efficient ternary bulk heterojunction,the 50 cm^(2) OPVmodules exhibited a PCE of 15.2%with respect to the active area.Importantly,the ternary OPV cells retain 80%of its initial PCE after 4000 h under continuous illumination.Our work demonstrates that the addition of a third component has the potential to improve the efficiency and stability of large-area organic solar cells.

关键词： organic photovoltaic cells morphology control large area cells ternary strategy power conventional efficiency

morphology and strain control of hierarchical cobalt oxide nanowire electrocatalysts via solvent effect

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Nano Research 2020年第11期13卷 3130-3136页

作者： Xiuming Bu Xiongyi Liang Kingsley O.Egbo Zebiao Li You Meng Quan Quan Yang Yang Li Kin Man Yu Chi-Man Lawrence Wu Johnny C.Ho Department of Materials Science and Engineering City University of Hong KongKowloonHong Kong SARChina Department of Physics City University of Hong KongKowloonHong KongKowloonHong Kong SARChina State Key Laboratory of Terahertz and Millimeter Waves City University of Hong KongKowloonHong Kong SARChina

Designing highly efficient and low-cost electrocatalysts for oxygen evolution reaction is important for many renewable energy applications.In particular,strain engineering has been demonstrated as a powerful strategy to enhance the electrochemical performance of catalysts;however,the required complex catalyst preparation process restricts the implementation of strain engineering.Herein,we report a simple self-template method to prepare hierarchical porous Co_(3)O_(4)nanowires(PNWs)with tunable compressive strain via thermal-oxidation-transformation of easily prepared oxalic acid-cobalt nitrate(Co(NO_(3))_(2))composite nanowires.Based on the complementary theoretical and experimental studies,the selection of proper solvents in the catalyst preparation is not only vital for the hierarchical structural evolution of Co_(3)O_(4) but also for regulating their compressive surface strain.Because of the rich surface active sites and optimized electronic Co d band centers,the PNWs exhibit the excellent activity and stability for oxygen evolution reaction,delivering a low overpotential of 319 mV at 10 mA·cm^(−2)in 1 M KOH with a mass loading 0.553 mg·cm^(−2),which is even better than the noble metal catalyst of RuO_(2).This work provides a cost-effective example of porous Co_(3)O_(4)nanowire preparation as well as a promising method for modification of surface strain for the enhanced electrochemical performance.

关键词： hierarchical structure morphology control compressive strain solvent effect oxygen evolution reaction

Solution sequential deposited organic photovoltaics:From morphology control to large-area modules

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eScience 2023年第4期3卷 39-64页

作者： Jianhua Jing Yuejia Dou Shihao Chen Kai Zhang Fei Huang Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640PR China

Organic optoelectronic materials enable cutting-edge,low-cost organic photodiodes,including organic solar cells(OSCs)for energy conversion and organic photodetectors(OPDs)for image sensors.The bulk heterojunction(BHJ)structure,derived by blending donor and acceptor materials in a single solution,has dominated in the construction of active layer,but its morphological evolution during film formation poses a great challenge for obtaining an ideal nanoscale morphology to maximize exciton dissociation and minimize nongeminate recom-bination.Solution sequential deposition(SSD)can deliver favorable p–i–n vertical component distribution with abundant donor/acceptor interfaces and relatively neat donor and acceptor phases near electrodes,making it highly promising for excellent device performance and long-term stability.Focusing on the p–i–n structure,this review provides a systematic retrospect on regulating this morphology in SSD by summarizing solvent selection and additive strategies.These methods have been successfully implemented to achieve well-defined morphology in ternary OSCs,all-polymer solar cells,and OPDs.To provide a practical perspective,comparative studies of device stability with BHJ and SSD film are also discussed,and we review influential progress in blade-coating techniques and large-area modules to shed light on industrial production.Finally,challenging issues are out-lined for further research toward eventual commercialization.

关键词： Organic solar cells Organic photodetectors Solution sequential deposition Solution processed planar heterojunction morphology control

“Toolbox”for the Processing of Functional Polymer Composites

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Nano-Micro Letters 2022年第2期14卷 216-256页

作者： Yun Wei Hongju Zhou Hua Deng Wenjing Ji Ke Tian Zhuyu Ma Kaiyi Zhang Qiang Fu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065People’s Republic of China

Functional polymer composites(FPCs)have attracted increasing attention in recent decades due to their great potential in delivering a wide range of functionalities.These functionalities are largely determined by functional fillers and their network morphology in polymer matrix.In recent years,a large number of studies on morphology control and interfacial modification have been reported,where numerous preparation methods and exciting performance of FPCs have been reported.Despite the fact that these FPCs have many similarities because they are all consisting of functional inorganic fillers and polymer matrices,review on the overall progress of FPCs is still missing,and especially the overall processing strategy for these composites is urgently needed.Herein,a"Toolbox"for the processing of FPCs is proposed to summarize and analyze the overall processing strategies and corresponding morphology evolution for FPCs.From this perspective,the morphological control methods already utilized for various FPCs are systematically reviewed,so that guidelines or even predictions on the processing strategies of various FPCs as well as multi-functional polymer composites could be given.This review should be able to provide interesting insights for the field of FPCs and boost future intelligent design of various FPCs.

关键词： Toolbox Functional polymer composites Processing strategy morphology control

Advances in Green-Solvent-Processable All-Polymer Solar Cells

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Chinese Journal of Polymer Science 2022年第8期40卷 846-860,I0006页

作者： Qingqing Bai Huiliang Sun Xugang Guo Li Niu Center for Advanced Analytical Science School of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou510006China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen518055China Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou510640China

All-polymer solar cells(all-PSCs)have significantly improved long-term stability and mechanical stretchability.The power conversion efficiency(PCE)of all-PSCs has been rapidly improved from∼1%to now over∼17%,driven by rational molecular design,blend morphology optimization,and device engineering.However,most all-PSCs are generally processed with halogenated solvents,hazardous for human health and the global environment.Achieving high-performance all-PSCs with halogen-free solvent processing remains a challenge.This feature article presents recent advances in green-solvent-processable all-PSCs from the material design and morphological control perspective,and further reviews progress in using more environmentally friendly solvents(i.e.,water or alcohol)to achieve genuinely sustainable and environmentally friendly manufacturing all-PSCs.Finally,we provide an outlook on the challenges and opportunities for large-scale manufacturing of green-solvent-processable all-PSCs.

关键词： All-polymer solar cells Green solvent Molecular design morphology control