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Insight into the mechanism of 5-hydroxymethylfurfural electroreduction to 2,5-bis(hydroxymethyl)furan over Cu anchored N-doped carbon nanosheets

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Nano Research 2024年第9期17卷 7991-7999页

作者： haoran Wu Xinwei chen haishan Xu Runlu Yang Xin Wang Junying chen Zhenbing Xie Liang Wu Yiyong Mai School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgeingShanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry Tangshan Normal UniversityTangshan 063000China

Design of non-noble metal electrocatalysts for biomass conversion to high-value chemicals and understanding the related catalytic mechanisms are of profound significance but have remained a major ***,we developed a novel biomass-derived electrocatalyst(denoted as Cu/NC),featuring with electron-deficient copper nanoparticles anchored on N-doped carbon nanosheets,for the electrochemical reduction of 5-hydroxymethylfurfural(hMF)to 2,5-bis(hydroxymethyl)furan(BhMF,a vital precursor of functional polymers).The optimized Cu/NC electrocatalyst exhibited an excellent performance with high Faradaic efficiency(89.5%)and selectivity(90.8%)of BhMF at a low concentration of hMF(18.1 mM).Even at a very high hMF concentration(108.6 mM),the Faraday efficiency and selectivity of BhMF could still reach 74.8%and 81.1%,*** performance approached those of the reported noble metal-based *** study revealed that the N doping in the Cu/NC catalyst could regulate the electronic structure of Cu,strengthening the adsorption of the hMF carbonyl group,and thus boosting the selectivity of ***,strong electronic metal-support interactions of Cu and the N-doped carbon support optimized the charge transfer rate,thus promoting the dissociation of water to the active hydrogen(h^(*))species and boosting the reaction kinetic rate of h^(*)and hMF.

关键词： biomass 5-hydroxymethylfurfural electrochemical reduction N-doped carbon materials 2,5-bis(hydroxymethyl)furan

Wavelength injection locking actively Q-switched random fiber laser based on random phase-shifted fiber Bragg grating and electro-optic modulator

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Optoelectronics Letters 2024年第3期20卷 135-141页

作者： PAN honggang ZhANG Bo SONG Dianyou chen Zhipan chen Chunqi LI Rupeng School of Integrated Circuit Science and Engineering Tianjin University of TechnologyTianjin 300384China

In this paper, an actively Q-switched wavelength injection locking random fiber laser(RFL) based on random phase-shifted fiber Bragg grating(RPS-FBG) is proposed, and the performance of the laser is verified by experiments. Within the reflection bandwidth range of RPS-FBG, spanning from 1 549.2 nm to 1 549.9 nm, different laser modes with stable central wavelength and peak power can be selectively chosen by varying the injected light wavelength. The power fluctuation within 1 h is less than 0.1 d Bm, and the central wavelength drift is less than 0.02 nm. When the pump power increases from 90 mW to 300 mW, the pulse width decreases from 3.2 μs to 1.5 μs, and the pulse repetition frequency is 20 khz. The RFL can reach a stable locking state at the lowest pump power of 100 mW and the lowest injection power of 3 d Bm. When the wavelength is locked, the output pulse is a single pulse. On the contrary, the unlocked output pulse is multi-pulse. The laser has the characteristics of high wavelength tunability in the reflection range of RPS-FBG and it can be an ideal light source in the fields of laser imaging and pulse coding.

关键词： fiber switched modulator

Reasonable design a high-entropy garnet-type solid electrolyte for all-solid-state lithium batteries

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Journal of Energy Chemistry 2024年第9期96卷 414-423页

作者： Shiyu Yu Yandi Li Jiaxin Luo Daming chen Liang Yang Yaqing Wei De Li Yuanxun Li Yong chen State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science1nd EngineeringHainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti ResourcesHainan UniversityHaikou 570228HainanChina State Key Laboratory of Electronic Thin Films1nd Integrated Devices University of Electronic Science1nd Technology of ChinaChengdu 610054SichuanChina Guangdong Key Laboratory for hydrogen Energy Technologies School of Materials Science1nd Hydrogen EnergyFoshan UniversityFoshan 528000GuangdongChina

Traditional garnet solid electrolyte(Li_(7)La_(3)Zr_(2)O_(12))suffers from low room temperature ionic conductivity,poor air stability,high sintering temperature and energy *** the development prospects of high-entropy materials with high structural disorder and strong component controllability in the field of electrochemical energy storage,herein,a novel high-entropy garnet-type oxide solid electrolyte,Li_(5.75)Ga_(0.25)La_(3)Zr_(0.5)Ti_(0.5)Sn_(0.5)Nb_(0.5)O_(12)(LGLZTSNO)was constructed by partially replacing the Li and Zr sites in Li_(7)La_(3)Zr_(2)O_(12)with Ga and Ti/Sn/Nb elements,*** experimental and density functional theory(DFT)calculation results show that the high-entropy LGLZTSNO electrolyte has preferable room temperature ion conductivity,air stability,interface contact performance with lithium anode,and the ability to suppress lithium *** to the improvement of electrolyte performance,the critical current density of Li/Ag@LGLZTSNO/Li symmetric cell was increased from 0.42 to 1.57 mA cm^(−2),and the interface area specific impedance(IASR)was reduced from 765.2 to 42.3Ωcm^(2).Meanwhile,the Li/Ag@LGLZTSNO/LFP full cell also exhibits excellent rate performance and cycling performance(148 mA h g^(−1)at 0.1 C and 124 mA h g^(−1)at 0.5 C,capacity retention up to 84.8%after 100 cycles at 0.1 C),showing the application prospects of high-entropy LGLZTSNO solid electrolyte in high-performance all solid state lithium batteries.

关键词： Garnet solid electrolyte Dual-site substitution high-entropy all solid-state lithium batteries(ASSLBs)

Application of novel constrained friction processing method to produce fine grained biomedical Mg-Zn-Ca alloy

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Journal of Magnesium and Alloys 2024年第2期12卷 516-529页

作者： Ting chen Banglong Fu Junjun Shen Uceu F.h.R.Suhuddin Björn Wiese Yuanding huang Min Wang Jorge F.dos Santos Jean Pierre Bergmann Benjamin Klusemann Solid State Materials Processing Institute of Material MechanicsHelmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany Functional Magnesium Materials Institute of Metallic BiomaterialsHelmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany Shanghai Key Laboratory of Materials Laser Processing and Modification Shanghai Jiao Tong UniversityDongchuan Road 800Shanghai 200240China Applied Materials and Manufacturing Energy and Environment DivisionPacific Northwest National LaboratoryPO Box 999RichlandWA 99352USA Production Technology Group Technisiche Universität IlmenauGustav-Kirchhoff-Platz 2Ilmenau 98693Germany Institute for Production Technology and Systems Leuphana University of LüneburgUniversitätsallee 1Lüneburg 21335Germany

In order to obtain Mg alloys with fine microstructures and high mechanical performances,a novel friction-based processing method,name as“constrained friction processing(CFP)”,was *** CFP,defect-free Mg-Zn-Ca rods with greatly refined grains and high mechanical properties were *** to the previous as-cast microstructure,the grain size was reduced from more than 1 mm to around 4μm within 3 s by a single process *** compressive yield strength was increased by 350%while the ultimate compressive strength by 53%.According to the established material flow behaviors by“tracer material”,the plastic material was transported by shear *** the base material to the rod,the material experienced three stages,*** by the tool,upward flow with additional tilt,followed by upward *** microstructural evolution was revealed by“stop-action”*** microstructural development at regions adjacent to the rod is mainly controlled by twinning,dynamic recrystallization(DRX)as well as particle stimulated nucleation,while that within the rod is related to DRX combined with grain growth.

关键词： Constrained friction processing Magnesium alloys Microstructure Mechanical properties Grain refinement Plastic deformation

Polyoxometalates for continuous power generation by atmospheric humidity

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Nano Research 2024年第3期17卷 1875-1885页

作者： Tuo Ji Weilin chen Zhenhui Kang Liming Zhang Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Northeast Normal UniversityChangchun 130024China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices DepartmentSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering Macao University of Science and TechnologyTaipaMacao 999078China Institute of Functional State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Atmospheric humidity is a sustainable low-value energy widely existing in natural environment,which is a promising candidate to solve the noncontinuous and low efficiency of low-value energy power *** the mono-substituted Dawson-type polyoxometalates are constructed to be highly dispersed organic ammonium-polyoxoanion clusters and are assembled into thin films power generators with micropores,working in atmospheric *** optimal polyoxometalates generator with the thickness of 7.2μm and the area of 0.36 cm^(2) produces a voltage of 0.68 V and a current density of 19.5μA·cm^(-2) under simulated natural environment,and works continuously and stably under almost all-natural environments(humidity 10%–90%).The highly dispersed polyoxometalate nanoclusters can form microporous in polyoxometalate films to effectively absorb atmospheric humidity and spontaneously form distribution gradient of water,which is the structural basis of power *** continuous power generation may be maintained by the effective adsorption and utilization of h_(2)O,the huge electrostatic field of organic ammonium-polyoxoanion clusters,and the reasonably designed polyoxometalates containing inorganic small ions with high *** is the first humidity generator designed with polyoxometalates,which may provide a new research direction for polyoxometalates in sustainable utilization of low-value energy.

关键词： atmospheric humidity continuous power generations nanomaterials polyoxoanions polyoxometalates

Small amount but big impact:Trace oxygen interstitially inserted PtCu alloys by microalloying for efficient oxygen reduction catalysis

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Nano Research 2024年第8期17卷 7001-7012页

作者： Qiheng Wang Zhiguo chen Jingyan Zhang Jingjun Liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

The introduction of small size non-metal elements(e.g.,oxygen)into solid solution alloys may be a promising strategy for fabricating efficient Pt-based catalysts with high activity and stability toward oxygen reduction reaction(ORR).herein,oxygen interstitially inserted PtCu(O-PtCu)alloys are firstly designed by an oxygen-microalloying strategy,through ultraviolet(UV)irradiation-assisted galvanic replacement in an aqueous solution containing h_(2)PtCl_(6)and Cu_(2)O nanowires as sacrificial *** obtained O-PtCu alloys feature a typical face-centered cubic(FCC)structure with majority Pt,Cu atoms as building bricks and trace interstitial oxygen(1.65 wt.%)existed in the octahedral sites surrounding Cu atoms,leading to a short-range disordered *** alloy reaches a recorded half-wave potential of 0.96 V(*** hydrogen electrode(RhE))and mass activity of 0.48 A·mgPt^(−1),much higher than those of commercial Pt/*** the accelerated degradation test(ADT),the mass activity lost only 4.2%after 10k cycles,while the commercial Pt/C lost 66.7%under the same *** with pure Pt and undoped PtCu alloy,the remarkably improved performance can be attributed to the lattice distortion and energy band reconstruction caused by the interstitial oxygen atoms in form of Cu–O ***,the stable Cu–O bonds delay the possible place exchange between surface Pt atoms and surface-adsorbed oxygen species,thereby hindering Pt dissolution,providing a new paradigm to address Pt degradation ***,the introduction of interstitial oxygen into Pt-based alloys may be a facile and smart strategy for the development of advanced Pt-based alloys electrocatalysts.

关键词： oxygen-microalloying platinum alloys octahedral interstices oxygen reduction reaction

Molecular packing tuning via chlorinated end group enables efficient binary organic solar cells over 18.5%

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Carbon Energy 2024年第3期6卷 196-203页

作者： Yafeng Li Zhenyu chen Xingzheng Yan Ziyi Ge Zhejiang Business Technology Institute NingboZhejiangChina Zhejiang Engineering Research Center for Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboZhejiangChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina

Designing novel nonfullerene acceptors(NFAs)is of vital importance for the development of organic solar cells(OSC).Modification on the side chain and end group are two powerful tools to construct efficient ***,based on the high-performance L8BO,we selected 3-ethylheptyl to substitute the inner chain of 2-ethylhexyl,obtaining the backbone of *** we introduced different halogen atoms of fluorine and chlorine on 2-(3-oxo-2,3-dihydro-1hinden-1-ylidene)malononitrile end group(EG)to construct efficient NFAs named BON3-F and BON3-Cl,*** donor D18 was chosen to combine with two novel NFAs to construct OSC ***,D18:BON3-Cl-based device shows a remarkable power conversion efficiency(PCE)of 18.57%,with a high open-circuit voltage(V_(OC))of 0.907 V and an excellent fill factor(FF)of 80.44%,which is one of the highest binary PCE of devices based on D18 as the ***,BON3-F-based device shows a relatively lower PCE of 17.79%with a decreased FF of 79.05%.The better photovoltaic performance is mainly attributed to the red-shifted absorption,higher electron and hole mobilities,reduced charge recombination,and enhanced molecular packing in the D18:BON3-Cl ***,we performed stability tests on two binary systems;the D18:BON3-Cl and D18:BON3-F devices maintain 88.1%and 85.5%of their initial efficiencies after 169 h of storage at 85°C in an N2-filled glove box,*** work demonstrates the importance of selecting halogen atoms on EG and provides an efficient binary system of D18:BON3-Cl for further improvement of PCE.

关键词： binary organic solar cell chlorinated end group molecular packing

Combined effect of WS_(2) and Ti_(3)C_(2)T_(x) MXene favors oil-based ultra-low friction on rough steel-steel interface at elevated temperatures

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Science China(Technological Sciences) 2024年第7期67卷 1991-2002页

作者： LIU YangQin chen Lei WANG Yang QIAN LinMao Tribology Research Institute State Key Laboratory of Rail Transit Vehicle SystemSchool of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Advanced Technologies of Materials(Ministry of Education) Research Institute of Frontier ScienceSouthwest Jiaotong UniversityChengdu 610031China

The lubrication performance of liquids is severely restricted and is degraded in high-temperature environments. Stable and reliable lubrication in high temperature environments has been a long-standing goal in various industrial fields. In this study,WS_(2)and Ti_(3)C_(2)T_(x)MXene nanoflakes were used as oil-based lubricant additives to generate ultra-low friction and even superlubricity(friction coefficient of ~0.007) at elevated temperatures(400℃), which has hitherto not been achieved by both individual pristine materials, WS_(2)and Ti_(3)C_(2)T_(x)MXene. Viscosity and thermogravimetric characterization revealed improvements in the high-temperature rheological properties and thermal stability of the lubricating base oil, indicating improved loadbearing and continuous lubrication capabilities at elevated temperatures. X-ray photoelectron spectroscopy, transmission electron microscopy, and atomic force microscopy demonstrated that the formation of an iron/titanium/tungsten-rich oxide lubricious thin film at the sliding interface reduced the interfacial shear stress, which was responsible for the observed friction and wear reductions at high contact pressures(> 1.1 GPa). Although the titanium/tungsten oxide film was gradually removed after prolonged sliding, a sufficiently thick iron oxide film maintained a low friction coefficient for at least 2 h. The improved surface quality facilitates the achievement of ultra-low friction and reduced wear. The proposed lubrication methodology has a broad utilization potential as a wear-reduction strategy across various industrial fields at elevated temperatures.

关键词： ultra-low friction high-temperature wear reduction lubricating additive tungsten disulfide MXene

Anchoring heterometallic cluster on P-doped carbon nitride for efficient photocatalytic nitrogen fixation in water and air ambient

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Chinese Chemical Letters 2024年第4期35卷 176-180页

作者： Chao-Long chen Rong chen La-Sheng Long Lan-Sun Zheng Xiang-Jian Kong Collaborative Innovation Center of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Light-driven nitrogen fixation to produce ammonia is a green and economical technology of nitrogen reduction but is still quite challenging, especially in an air atmosphere without any sacrificial ***, we demonstrate efficient photocatalytic nitrogen fixation using water and air directly by loading lanthanide–transition metal(4f–3d) cluster NdCo_(3) on two-dimensional P-doped graphitic carbon nitrides(PCN) material surface. Benefiting from the increase in the number of nitrogen vacancies(NVs) and highly matched band gap structure and excellent hole trapping ability of clusters, the NdCo_(3)/PCN photocatalyst exhibits efficient nitrogen reduction activity with 371(in air) and 825 μmol h^(-1)g^(-1)(in pure nitrogen)without any sacrificial reagents. The introduction of potassium sulfate inhibits hydrogen production and promotes nitrogen reduction activation. This work suggests that anchoring precisely structured clusters on 2D materials may enhance photocatalytic nitrogen reduction under normal temperature and pressure.

关键词： Photocatalytic Nitrogen fixation 4f-3d Cluster Air atmosphere