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Surface-induced Microstructure and Performance Changes in P3HT Ultrathin Films

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Chinese Journal of Polymer Science 2024年第6期42卷 805-814页

作者： Hong-Tao Shan Jia-Xin He Bing-Yan Zhu Xue-Ting Cao Ying-Ying Yan Jian-Jun Zhou Hong Huo beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing100875China

In this work,poly(3-hexylthiophene)(P3HT)ultrathin films(P3HT-T)were prepared by spin-coating a dilute P3HT solution(in a toluene:o-dichlorobenzene(Tol:ODCB)blend with a volume ratio of 80:20)with ultrasonication and the addition of the nucleating agent bicycle[2.2.1]heptane-2,3-dicarboxylic acid disodium salt(HPN-68L)on glass,Si wafers and indium tin oxide(ITO)*** electrical and mechanical properties of the P3HT-T ultrathin films were investigated,and it was found that the conductivity and crack onset strain(COS)were simultaneously improved in comparison with those of the corresponding pristine P3HT film(P3HT-0,without ultrasonication and nucleating agent)on the same substrate,regardless of what substrate was ***,the conductivity of P3HT-T ultrathin films on different substrates was similar(varying from 3.7 S·cm^(-1)to 4.4 S·cm^(-1)),yet the COS increased from 97%to 138%by varying the substrate from a Si wafer to *** grazing-incidence wide-angle X-ray diffraction(GIXRD),UV-visible(UV-Vis)spectroscopy and atomic force microscopy(AFM),we found that the solid order and crystallinity of the P3HT-T ultrathin film on the Si wafer are highest,followed by those on glass,and much lower on ***,the surface energy and roughness of three substrates were investigated,and it was found that the polar component of the surface energyγp plays a critical role in determining the crystalline microstructures of P3HT ultrathin films on different *** work indicates that the P3HT ultrathin film can obviously improve the stretchability and simultaneously retain similar electrical performance when a suitable substrate is *** findings offer a new direction for research on stretchable CP ultrathin films to facilitate future practical applications.

关键词： P3HT ultrathin film Substrate Crystalline microstructures Polar component of the surface energy Electrical and stretchable performances

Coupling interface constructions of hollow Co-Mo mixed multiple oxidation states heterostructure for high-performance aprotic Li-O_(2) battery

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Nano Research 2024年第5期17卷 4100-4107页

作者： Xingzi Zheng Mengwei Yuan Jingshen Xu Zihan Li Caiyun Nan Genban Sun beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Materials Research Beijing Normal UniversityZhuhai 519087China

Constructing interfaces in heterostructures is effective for modulating the electronic properties of *** hollow CoMoO_(4)-Co_(3)O_(4) heterostructure(HCMCH)was prepared as a bifunctional electrocatalyst for Li-O_(2) *** different components in CoMoO_(4)-Co_(3)O_(4) heterostructure presented the efficient coupling and enhanced the electrocatalytic activity for aprotic oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),in which it improved the obviously reduced overpotential of 300 mV(compared with the pure Ketjen black(KB)electrode),enhanced reversibility of 80%capacity retention after 6 full cycles and the superior cyclability of more than 200 cycles with an optimized *** battery performance of the HCMCH was not only associated with the unique hollow structure and rich active sites but also with coupling interface constructions synergetic effects attaching to the improving conductivity and optimized the discharge *** results suggested that this HCMCH electrocatalyst was a promising candidate for the Li-O_(2) battery and it gave a novel insight for high performance electrocatalyst designing.

关键词： Li-oxygen battery heterostructure electrocatalyst coupling interface

Flower-like CuS/γ-Fe_(2)O_(3) van der Waals heterostructures with highefficient electromagnetic wave absorption

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Nano Research 2024年第4期17卷 3324-3333页

作者： Na Lu Jingshen Xu Mengwei Yuan Genban Sun beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Materials Research Beijing Normal UniversityZhuhai 519087China

The escalating electromagnetic(EM)pollution issues and the demand to elevate military stealth technology make it imperative to develop cost-effective and high-performance electromagnetic wave(EMW)absorbing *** this paper,the flower-like CuS/γ-Fe_(2)O_(3) van der Waals(vdW)heterostructures have been synthesized via a facile two-step solvothermal *** flower-like CuS skeleton increases the attenuation path of EMW while reducing the material *** contents ofγ-Fe_(2)O_(3) nanoparticles anchor between the flower-like CuS nanosheets to constitute a heterogeneous structure,which enables dielectric and magnetic loss synergistically to optimize impedance matching and remarkably improve the EMW absorption *** minimum reflection loss(RLmin)is-49.36 dB with a thickness of only 1.6 mm and the effective absorption bandwidth(EAB)reaches 4.64 GHz(13.36–18 GHz).By adjusting the thickness of the absorber,the EAB can cover 96%of the GHz ***,the superior absorption of-61.53 dB at middle frequency band can be obtained by adjusting the amount of Fe_(2)O_(3) *** this study,the adjustment of EM parameters and the optimization of impedance matching have been achieved by constructing a novel vdW heterogeneous structure,which provides fresh ideas and references for the design of high-performance EMW absorbing materials.

关键词： flower-like CuS γ-Fe_(2)O_(3) van der Waals heterostructures impedance matching electromagnetic wave absorption

A novel structure of ultra-high-loading small moleculesencapsulated ZIF-8 colloid particles

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Nano Research 2024年第4期17卷 2929-2940页

作者： Pengfei Duan Yunhe An Xiaoxiao Wei Yanjie Tian Di Guan Xiangwen Liu Lanqun Mao Institute of Analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100089China college of chemistry Beijing Normal UniversityBeijing 100875China

The safety of nanoparticle-based drug delivery systems(DDSs)for cancer treatment is still a challenge,restricted by the intrinsic cytotoxicity of drug carriers and leakage of loaded ***,we propose a novel nanocarrier’s cytotoxicity avoidance strategy by synthesizing an encapsulation core–shell structure of zeolitic imidazolate framework-8(ZIF-8)-based colloid particles(CPs)with an amorphous ZIF-8 *** encapsulation structure achieves an ultra-high loading rate(LR)of 90%(i.e.,9 mg doxorubicin(DOX)per 1 mg ZIF-8)for DOX and the protection of DOX from ***,to deliver unit-dose drug,this ultra-high LR of 90%significantly reduces the usage of ZIF-8 to 1.2%(2 orders of magnitude)compared to that of DOX@ZIF-8 with a 10%LR,in which cytotoxicity of ZIF-8 could well below the safety limit and then be relatively ***,drug delivery efficacy,scale-up ability,and universality of this encapsulation structure have been further *** findings suggest the great potential of this ZIF-8-based encapsulation core–shell structure in the field of drug delivery.

关键词： metal-organic frameworks zeolitic imidazolate framework-8(ZIF-8) drug delivery nanoparticles nanostructures

Optimal geometrical configuration and oxidation state of cobalt cations in spinel oxides to promote the performance of Li-O_(2) battery

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Nano Research 2024年第1期17卷 221-227页

作者： Yu Zhang Shuting Zhang Mengwei Yuan Yufeng Li Rong Liu Caiyun Nan Chen Chen Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875China X-ray diffraction Lab Analytical and Testing CenterBeijing Normal UniversityBeijing 100875China

Co_(3)O_(4) is considered as one of promising cathode catalysts for lithium oxygen(Li-O_(2))batteries,which contains both tetrahedral Co^(2+)sites(Co^(2+)Td)and octahedral Co^(3+)sites(Co^(3+)Oh).It is important to reveal the effect of optimal geometric configuration and oxidation state of cobalt ion in Co_(3)O_(4) to improve the performance of Li-O_(2) ***,through regulating the synthesis process,Co^(2+)and Co^(3+)sites in Co_(3)O_(4) were replaced with Zn and Al atoms to form materials with a unique Co *** Li-O_(2) batteries based on ZnCo_(2)O_(4) showed longer cycle life than that of CoAl_(2)O_(4),suggesting that in Co_(3)O_(4),the Co^(3+)Oh site is a relatively better geometric configuration than Co^(2+)Td site for Li-O_(2) *** calculations revealed that Co^(3+)Oh sites provide higher catalysis activity,regulating the adsorption energy of the intermediate LiO_(2) and accelerating the kinetics of the reaction in batteries,which further leads to the change of the morphology of the discharge product and ultimately improves the electrochemical performance of the batteries.

关键词： lithium oxygen(Li-O_(2))batteries geometrical configuration oxidation state lithium peroxide

Spatially explicit reconstruction of cropland cover in Europe from AD 1800 to 2000

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Science china Earth Sciences 2024年第9期67卷 2953-2971页

作者： Jun LI Yu YE Xiuqi FANG Diyang ZHANG Zhilei WU Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China college of Geographical Science Qinghai Normal UniversityXining 810016China

One of the challenges in global change research is the significant uncertainty in global historical land use and land cover(LUCC)datasets,which are widely used as foundational *** addition to the regional cropland area reconstructions,improving the grid allocation method is another feasible way to raise the reliability of historical LUCC *** this study,an integrated reconstruction of the national cropland areas over the past 200 years was developed for 36 European *** that,the allocation algorithm was built using physiogeographic variables and historical city sites for accounting for land suitability and cultivation preferences,***,cropland data in Europe with a spatial resolution of 5′×5′at five time sections from AD 1800 to 2000 were generated using the optimal allocation algorithm in accordance with the stages of the regional *** results were as follows:(1)The dominant factors governing the distribution of croplands in Europe vary at different agricultural stages,but the results can be merged *** suitability was more optimal for allocation during the modern agricultural stage(AD 1950 and 2000);the priority index combined with land suitability and cultivation preference was more reasonable for allocation during the traditional agricultural stage(AD 1800).The average of the allocations by priority index and the land suitability could be adopted as the allocation results during the transitional stage(AD 1850 and 1900)because the grids for absolute differences within±10 and±20 percentage points between the results obtained from the above two allocations were above 80% and 95%,respectively,which means the two allocation results could be merged.(2)Over the past 200 years,the total cropland area in Europe first increased to a peak in AD 1900 and then ***,the centre of the higher cropland fraction shifted from the western part of Europe in AD 1800 to the eastern part of the continent after AD 1950.(3)

关键词： Land use and land cover change Historical cropland Gridding allocation Europe Past 200 years

Imaging plate scanners calibration and the attenuation behavior of imaging plate signals

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Chinese Physics B 2024年第6期33卷 38-44页

作者：薄楠王乃彦 college of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China china Institute of Atomic Energy Beijing 102413China

Based on previously reported work, we propose a new method for calibrating image plate(IP) scanners, offering greater flexibility and convenience, which can be extended to the calibration tasks of various scanner models. This method was applied to calibrate the sensitivity of a GE Typhoon FLA 7000 scanner. Additionally, we performed a calibration of the spontaneous signal attenuation behavior for BAS-MS, BAS-SR, and BAS-TR type IPs under the 20±1℃ environmental conditions, and observed significant signal carrier diffusion behavior in BAS-MS IP. The calibration results lay a foundation for further research on the interaction between ultra-short, ultra-intense lasers and matter.

关键词： image plate scanner ultra-short ultra-intense lasers

Scattered Co-anchored MoS_(2)synergistically boosting photothermal capture and storage of phase change materials

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Journal of Energy chemistry 2024年第8期95卷 208-215,I0005页

作者： Yang Li Panpan Liu Yan Gao Yuhao Feng Peicheng Li Xiao Chen Institute of Advanced Materials Beijing Normal UniversityBeijing 100875China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Environment Beijing Normal UniversityBeijing 100875China

Pristine phase change materials(PCMs)suffer from inherent deficiencies of poor solar absorption and photothermal ***,we proposed a strategy of co-incorporation of zero-dimensional(OD)metal nanoparticles and two-dimensional(2D)photothermal materials in PCMs for efficient capture and conversion of solar energy into thermal *** scattered Co-anchored MoS_(2)nanoflower cluster serving as photon and phonon triggers was prepared by in-situ hydrothermal growth of ZIF67 polyhedron on 2D MoS_(2)and subsequent high-temperature *** encapsulating thermal storage unit(paraffin wax),the obtained composite PCMs integrated high-performance photothermal conversion and thermal energy storage *** from the synergistic enhancement of OD Co nanoparticles with localized surface plasmon resonance effect,carbon layer with the conjugation effect and 2D MoS_(2)with strong solar absorption,composite PCMs exhibited a high photothermal conversion efficiency of 95.19%,Additionally,the resulting composite PCMs also demonstrated long-term thermal sto rage stability and durable structu ral stability after 300 thermal *** proposed collabo rative co-incorporation strategy provides some innovative references for developing next-generation photothermal PCMs in solar energy utilization.

关键词： Phase change materials Photothermal conversion Thermal energy storage

Flexible Crystal Heterojunctions of Low-Dimensional Organic Metal Halides Enabling Color-Tunable Space-Resolved Optical Waveguides

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Research 2024年第3期6卷 293-304页

作者： Yuhang Lin Shuya Liu Dongpeng Yan beijing Key Laboratory of Energy Conversion and Storage Materials and Key Laboratory of RadiopharmaceuticalsMinistry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China.

Molecular luminescent materials with optical waveguide have wide application prospects in light-emitting diodes, sensors, and logic gates. However, the majority of traditional optical waveguide systems are based on brittle molecular crystals, which limited the fabrication, transportation, storage, and adaptation of flexible devices under diverse application situations. To date, the design and synthesis of photofunctional materials with high flexibility, novel optical waveguide, and multi-port color-tunable emission in the same solid-state system remain an open challenge. Here, we have constructed new types of zero-dimensional organic metal halides (Au-4-dimethylaminopyridine [DMAP] and In-DMAP) with a rarely high elasticity and rather low loss coefficients for optical waveguide. Theoretical calculations on the intermolecular interactions showed that the high elasticity of 2 molecular crystalline materials was original from their herringbone structure and slip plane. Based on one-dimensional flexible microrods of 2 crystals and the 2-dimensional microplate of the Mn-DMAP, heterojunctions with multi-color and space-resolved optical waveguides have been fabricated. The formation mechanism of heterojunctions is based on the surface selective growth on account of the low lattice mismatch ratio between contacting crystal planes. Therefore, this work describes the first attempt to the design of metal-halide-based crystal heterojunctions with high flexibility and optical waveguide, expanding the prospects of traditional luminescent materials for smart optical devices, such as logic gates and multiplexers.

关键词： waveguide Crystal elasticity