Tailoring crystal plane of short-process regenerated LiFePO_(4) towards enhanced rate properties

Captured by the environmental and economic value,the recycling of spent lithium iron phosphate(LFP)batteries has attracted numerous attentions.However,hydrometallurgical method still suffers from complex process,and hydrothermal method is limited by morphology control,ascribed to the strong polarity of water.Herein,supported by ethanol as crystal surface modifier,the regular(010)orientation and short b-axis are effectively tailored for regenerated LFP.As Li-storage cathode,the capacities of as-optimized LFP could reach up to 157.07 mA h g^(-1)at 1 C,and the stable capacity of 150.50 mA h g^(-1)could be remained with retention of 93.48%after 400 cycles at 1 C.Even at 10 C,their capacity could be still kept about 119.3 m A h g^(-1).Assisted by the detail analysis of adsorption energy,the clear growth mechanism is proposed,the lowest adsorbing energy(-4.66 eV)of ethanol on(010)crystal plane renders the ordered growth along(010)crystal plane.Given this,the work is expected to shed light on the tailoring mechanism of internal plane about regenerated materials,whilst providing effective strategies for highperformance regenerated LFP.

Enhancing the crystallinity and stability of perovskite solar cells with 4-tert-butylpyridine induction for efficiency exceeding 24%

Perovskite solar cells(PSCs)have emerged as a promising photovoltaic technology because of their high light absorption coefficient,long carrier diffusion distance,and tunable bandgap.However,PSCs face challenges such as hysteresis effects and stability issues.In this study,we introduced a novel approach to improve film crystallization by leveraging 4-tert-butylpyridine(TBP)molecules,thereby enhancing the performance and stability of PSCs.Our findings demonstrate the effective removal of PbI_(2)from the perovskite surface through strong coordination with TBP molecules.Additionally,by carefully adjusting the concentration of the TBP solution,we achieved enhanced film crystallinity without disrupting the perovskite structure.The TBP-treated perovskite films exhibit a low defect density,improved crystallinity,and improved carrier lifetime.As a result,the PSCs manufactured with TBP treatment achieve power conversion efficiency(PCE)exceeding 24%.Moreover,we obtained the PCE of 21.39%for the 12.25 cm^(2)module.

Mitigating kinetic hindrance of single-crystal Ni-rich cathodes through morphology modulation,nickel reduction,and lithium vacancy generation achieved by terbium doping

Single crystallization has proven to be effective in enhancing the capacity and stability of Ni-rich LiNi_(1-x-y)Co_(x)Mn_(y)O_(2)(SNCM)cathode materials,particularly at high cut-off voltages.Nevertheless,the synthesis of high-quality single-crystal particles remains challenging because of severe particle agglomeration and irregular morphologies.Moreover,the limited kinetics of solid-phase Li^(+)diffusion pose a significant concern because of the extended diffusion path in large single-crystal particles.To address these challenges,we developed a Tb-doped single-crystal LiNi_(0.83)Co_(0.11)Mn_(0.06)O_(2)(SNCM-Tb)cathode material using a straightforward mixed molten salt sintering process.The Tb-doped Ni-rich single crystals presented a quasi-spherical morphology,which is markedly different from those reported in previous studies.Tb^(4+)oping significantly enhanced the dynamic transport of Li^(+)ions in the layered oxide phase by reducing the Ni valence state and creating Li vacancies.A SNCM-Tb material with 1 at%Tb doping shows a Li^(+)diffusion coefficient up to more than 9 times higher than pristine SNCM in the non-diluted state.In situ X-ray diffraction analysis demonstrated a significantly facilitated H1-H2-H3 phase transition in the SNCM-Tb materials,thereby enhancing their rate capacity and structural stability.SNCM-Tb exhibited a reversible capacity of 186.9 mA h g^(-1)at 5 C,retaining 94.6%capacity after 100 cycles at 0.5 C under a 4,5 V cut-off.Our study elucidates the Tb^(4+)doping mechanisms and proposes a scalable method for enhancing the performance of single-crystal Ni-rich NCM materials.

Surface deterioration dependent on the crystal facets of spinel LiNi_(0.5)Mn_(1.5)O_(4) cathode active material

The spinel LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)cathode active materials(CAMs)are considered a promising alternative to commercially available cathodes such as layered and polyanion oxide cathodes,primarily due to their notable safety and high energy density,particularly in their single-crystal type.Nevertheless,the industrial application of the LNMO CAMs is severely inhibited due to the interfacial deterioration and corrosion under proton-rich and high-voltage conditions.This study successfully designed and synthesized two typical types of crystal facets-exposed single-crystal LNMO CAMs.By tracking the electrochemical deterioration and chemical corrosion evolution,this study elucidates the surface degradation mechanisms and intrinsic instability of the LNMO,contingent upon their crystal facets.The(111)facet,due to its elevated surface energy,is found to be more susceptible to external attack compared to the(100)and(110)facets.Our study highlights the electrochemical corrosion stability of crystal plane engineering for spinel LNMO CAMs.

Analyses of Reaction Mechanisms among Different Sulfonation Reagents and m-Diphenylamine and Crystal Structures of the Formed Compounds

In the traditional process, m-phenylenediamine reacts with fuming sulfuric acid at high temperature to get intermediates, and then after dehydration occurs intramolecular rearrangement to get 2,4-diaminobenzenesulfonic acid. Traditional methods need to consume a lot of fuming sulfuric acid or concentrated sulfuric acid, resulting in high industrial large-scale production cost, more waste, and posing a serious environmental pollution risk. In this thesis, three different sulfonation reagents were used for the sulfonation reaction of m-phenylenediamine, and the reaction mechanisms and crystal structures of the three pathways were investigated. The three routes are: 1) one-step synthesis of monosulfonated compound 1 from raw material and sulfur trioxide (SO3);2) rapid reaction of raw material and chlorosulfonic acid to synthesize bisulfonated compound 2;3) direct eutectic crystallization of raw material and ordinary sulfuric acid to obtain compound 3. The crystal structure of the compounds synthesized by three paths was analyzed by X-ray single crystal diffraction, and compound 1 was characterized by NMR, Fourier infrared spectra, UV-visible spectrum and Mass spectrometry. The one-step synthesis of SO3 as a sulfonation reagent has the advantages of mild reaction conditions, simple operation and low cost.

两种镍基单晶高温合金组织演变和再结晶行为

以单晶高温合金CMSX-4和DD5为研究对象,设计并制备了一种含5级平台的单晶试板铸件,选取晶体取向基本相同的铸件研究其在经1300℃/2 h和1310℃/4 h两种固溶热处理后的再结晶行为。结果表明:CMSX-4比DD5具有更强的再结晶倾向。经1300℃固溶热处理后,CMSX-4单晶试板在第2~5级平台下端转角处均出现了再结晶现象,且随着固溶热处理温度的升高,再结晶的面积越大。而DD5单晶试板经1300℃固溶热处理后并未出现再结晶现象,当固溶温度升至1310℃时,仅在第4级外侧平台发现了较小面积的再结晶。铸态和固溶热处理态的CMSX-4合金显微缩孔和共晶组织含量均大于DD5合金。更高含量的共晶组织和显微缩孔为CMSX-4铸件提供了更多的再结晶形核位置和数量,而高于γ′相溶解温度的固溶热处理减弱了粗大γ′相对再结晶长大的钉扎阻碍作用,高熔点的碳化物以及残余共晶成为阻碍再结晶长大的重要影响因素。此外,高含量的Co元素降低了CMSX-4合金的层错能,使其表现出更高的再结晶倾向。

高光束质量平-凸谐振腔Nd∶YVO_(4)激光器

采用一种由878.6 nm激光二极管(LD)端面抽运Nd∶YVO_(4)晶体,获得高光束质量的1064 nm脉冲激光输出。使用Matlab软件对晶体热透镜焦距进行模拟分析,并通过软件计算选取合适的平-凸谐振腔腔型,缓解热效应的同时获得最佳输出状态。泵浦功率为48 W时获得平均输出功率15.03 W的1064 nm连续光输出。通过磷酸钛氧铷(RTP)电光调Q的方式,在重复频率为10 kHz时获得了稳定的1064 nm脉冲激光输出,最大输出平均功率为8.78 W,动-静转化比为72.9%,脉宽为8.70 ns,光束质量因子为1.2。实验结果表明:利用波长878.6 nm作为泵浦源并采用平-凸谐振腔的方式,有利于缓解晶体的热效应、提高光束质量、获得基模脉冲激光输出。

Efficient Near-Infrared Quantum Cutting in Tm3＋/yb3＋ Codoped LiYF4 Single Crystals for Solar Photovoltaic

Downconversion （DC） with emission of two near-infrared photons about 1000 nm for each blue photon absorbed was obtained in thulium （Tm3＋） and ytterbium （Yb3＋） codoped yt- trium lithium fluoride （LiYF4） single crystals grown by an improved Bridgman method. The luminescent properties of the crystals were measured through photoluminescence excitation, emission spectra and decay curves. Luminescence between 960 and 1050 nm from yb3＋： 2Fs/2--＋2FT/2 transition, which was originated from the DC from Tm3＋ ions to Yb3＋ ions, was observed under the excitation of blue photon at 465 nm. Moreover, the energy transfer processes were studied based on the Inokuti-Hirayama model, and the results indicated that the energy transfer from Tm3＋ to Yb3＋ was an electric dipole-dipole interaction. The max- imum quantum cutting efficiency approached with 0.49mo1% Tm3＋ and 5.99mo1% Yb3＋. increasing the energy efficiency of crystalline energy part of the solar spectrum. up to 167.5% in LiYF4 single crystal codoped Application of this crystal has prospects for Si solar cells by photon doubling of the high

Synthesis,Crystal Structure and Antimicrobial Study of a New Schiff Base 2-{(2'-Benzyl)iminoethyl}-5-methoxyphenol

The Schiff base, 2-{（2′-benzyl）iminoethyl}-5-methoxyphenol （C6H4CH2N=C（CH3）C6H3- （OMe-5）OH） 1, was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in the orthorhombic system, space group Pbca with a = 8.9849（10）, b = 13.2699（15）, c = 22.975（2） A ,V= 2739.3（5） A^3, Mr= 255.31, Z= 8, F（000） = 1088, Dc = 1.238 g/cm^3, T= 293 K, μ = 0.082 mm^-1, λ = 0.71073 .A, the final R = 0.0596 and wR = 0.1575 for 1934 observed reflections with I 〉 2σ（I）. The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method, and found to be active against the four test bacterial organisms.

Syntheses and Crystal Structures of 3,5-Diiodo-salicylalidehyde and 3,5-Diiodo-salicylalidene-4-nitroaniline

The title compounds, C7H4I2O2 1 and C13H7I2N2O3 2, have been synthesized and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P21/c with a = 9.802（2）, b = 13.867（3）, c = 7.364（2） A, β = 109.74（3）°, V= 942.1（3） A^3, Dc= 2.636 g/cm^3, C7H4I2O2, Mr= 373.90, F（000） = 672, μ = 6.627 mm^-1, Z = 4, R = 0.0459 and wR = 0.1018 for 1805 observed reflections （I 〉 2 σ（I））. Compound 2 belongs to the monoclinic system, space group P21/n with a = 9.015（2）, b = 12.024（2）, c = 14.072（3） A, β = 103.91（3）°, V = 1480.6（5） A^3, Dc= 2.216 g/cm^3, C13H7I2N2O3, Mr= 494.01, F（000） = 920, p = 4.255 mm^-1, Z = 4, R = 0.0777 and wR = 0.1757 for 2896 observed reflections （I 〉 2σ（I））. Compounds 1 and 2 were assayed for antibacterial activities against three Gram positive bacterial strains （B. subtilis, S. aureus and S. faecalis） and three Gram negative bacterial strains （E. coli, P. aeruginosa and E. cloacae） by MTr method. Fortunately, compound 2 is found to show potent antibacterial activity against these six bacterial strains.

Synthesis and Crystal Structure of 2(1-Phenyl-3-methyl-5-chloro-1H-pyrazol- 4-yl)-3-(1-naphthoylamido)-4-thiazolidinone

The crystal structure of 2(1-phenyl-3-methyl-5-chloro-1H-pyrazol-4-yl)-3-(1- naphthoylamido)-4-thiazolidinone (C24H19ClN4O2S, Mr = 462.94) has been determined by single- crystal X-ray diffraction method. The crystal belongs to monoclinic, space group P21/c with a = 11.623(5), b = 11.579(5), c = 16.619(7) ? b = 90.112(8), V = 2237(2) 3, Z = 4, Dc = 1.375 g/cm3, m = 0.294 mm-1, F(000) = 960, R = 0.0492 and wR = 0.0768 for 3932 unique reflections with 1897 observed ones (I > 2s(I)). X-ray analysis reveals that there exist both intra-and intermolecular hydrogen bonds in the crystal lattice.

Synthesis,Crystal Structure and Biological Activity of N-(2,6-Difluorobenzoyl)-N'-[5-(4-trifluoromethyl-phenyl)-1,3,4-thiadiazol-2-yl]ure

The title compound N-（2,6-difluorobenzoyl）-N＇-[5-（4-trifluoromethylphenyl）-1,3,4-thiadiazol-2-yl]urea（C17H9F5N4O2S,Mr = 428.34） has been synthesized by the reaction of 2-amino-5-（4-trifluoromethylphenyl）-1,3,4-thiadiazole with 2,6-difluorobenzoyl isocyanate,and its crystal structure was determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21/n with a = 10.7316（13）,b = 10.5617（13）,c = 16.037（2） ,β = 106.408（2）°,V = 1743.6（4） 3,Z = 4,Dc = 1.632 g/cm3,μ = 0.260 mm-1,F（000） = 864,the final R = 0.0599 and wR = 0.1420 for 3467 observed reflections with I〉 2σ（I）.The urea group,which adopts a planar configuration mediated by the intramolecular N-H...O hydrogen bond,is nearly coplanar with the thiadiazole and 4-trifluoromethylbenzene rings.The title compound was found to exhibit good fungicidal activity against Rhizoctonia solani and Botrytis cinerea.

Synthesis and Crystal Structure of Calix[4]arene Bearing a 1,8-Bis(propoxy)anthracene-9,10-dione

The title complex （C50H44C14O8） was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/n with a = 19.7768（4）, b =10.2085（2）, c = 21.2721（4）A,β= 97.153（1）°, V = 4261.23（14）A^3, Z = 4, Mr = 914.65, F（000） = 1904, Dc = 1.426 g/cm^3,μ = 0.336, the final R = 0.0550 and wR = 0.1647. The compound was structurally characterized by IR and ^1H NMR. The molecules are stacked through C-H...π interactions and intermolecular C-H...O hydrogen bonds.

Hydrothermal Syntheses and Crystal Structures of Six Complexes Constructed from 1,3,5-Benzenetricarboxylic Acid and 4'-(4-Pyridyl)-2,2':6',2''-terpyridine Mixed Ligands

Six new transition metal complexes, [Zn（HBTC）（PYTPY）]n·n PYTPY（1）, [Cu（HBTC）（PYTPY）]n·n PYTPY（2）, [Co（HBTC）（PYTPY）]n·n DMF（3）, [Mn（HBTC）（PYTPY）]n·n DMF（4）, [Cd（HBTC）（PYTPY）（H2O）]n·2nH2O（5）, and [Co（HBTC）（PYTPY）（H2O）2]（6）,（H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4＇-（4-pyridyl）-2,2＇：6＇,2＇＇-terpyridine, DMF = N,N？-dimethylformamide）, have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional（3D） supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties.

Isolation and Crystal Structure of Stigmast-4-ene-3,6-diol

The title compound (C29H50O2, Mr = 430.69) was isolated from the algae Halimeda xishaensis collected from the South China Sea. Its crystal structure was determined by single-crystal X-ray diffraction for the first time. The crystal belongs to orthorhombic, space group P212121 with a = 8.1560(13), b = 10.7861(18), c = 29.973(5) ? V = 2636.8(8) 3, Z = 4, Dc = 1.085 g/cm3, F(000) = 960, (Mo-K? = 4.533 mm-1, ?= 0.71073 ? S = 1.061, (?max = 0.382 and (?min = 0.244 e/?. The structure was refined to R = 0.0561 and wR = 0.1553 for 2711 observed reflections with I > 2(I). X-ray diffraction analysis reveals that the title compound has two ?OH groups, and the side chain is saturated. There exist two intermolecular hydrogen bonds between three molecules.

Synthesis and Crystal Structure of a New Copper(II) Complex with 4-Cyanobenzoic Acid

A new Cu（Ⅱ） complex [Cu（4-cba）（1,10-phen）（H2O）2]（NO3） （4-Hcba = 4-cyanobenzoic acid） has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by single-crystal X-ray diffraction. Crystallographic data： C20H16CuN4O7, Mr= 487.91, triclinic, space group PI, a = 7.8420（2）, b = 9.1070（2）, c = 15.1140（6） A, a = 76.889（9）, β = 81.332（11）, γ = 74.844（ 11）°, V = 1009.89（5） A^3, Z = 2, Dc = 1.605 g/cm^3, F（000） = 498, μ = 1.134 mm^-1, the final R = 0.0379 and wR = 0.0865 for 2977 observed reflections with 1 〉 2σ（Ⅰ）. The Cu（Ⅱ） atom is coordinated by two terminal water molecules, one chelating 1,10-phen molecule and one monodentate 4-cba ligand to form a slightly distorted square pyramid. The title complex molecules are connected through hydrogen bonds and π-π stacking interactions to generate a 2D layered network. The thermogravimetric analysis of the title complex has also been discussed.

Syntheses, Crystal Structures and Properties of Two Cd(Ⅱ) Coordination Polymers with Mixed Ligands of 2,5-Di(pyridin-4-yl)benzaldehyde and Carboxylates

A new ligand 2,5-di（pyridin-4-yl）benzaldehyde （L） was synthesized by the reaction of pyridin-4-yl-boronic acid with 2,5-dibromobenzaldehyde. Two novel CdII coordination polymers, [CdL（BDC）].DMF （1） and [CdL（BPDC）].4H2O （2） （BDC = 1,4-benzenedicarboxylate, BPDC = 4,4′-biphenyldicarboxylate）, have been constructed based on the mixed ligands of L and dicaboxylic acid via solvothermal synthesis, and characterized by IR, microanalysis, TGA, single and power X-ray diffraction, and their fluorescence properties were also investigated. 1 crystallizes in orthorhombic space group Pcca with a = 15.8236（3）, b = 16.0038（3）, c = 20.2207（3） A, V = 5120.64（16） A3, Z = 8, Mr = 633.83, Dc = 1.644 g/cm3, F（000） = 2528, GOOF = 1.130, the final R = 0.0568 and wR = 0.1513 for 4108 observed reflections with I〉 2σ（I）. 2 crystallizes in orthorhombic space group Pbcn with a = 29.1148（1）, b = 16.0120（6）, c = 16.7097（7） A, V = 7789.8（5） A3, Z = 8, Mr = 675.88, Dc = 1.153 g/cm3,/7（000） = 2712, GOOF = 1.088, the final R = 0.0670 and wR = 0.1805 for 6047 observed reflections with I〉 2σ（I）. The dinuclear Cd2（CO2）4 unit is linked by BDC in 1 to form a 2D sheet that is further pillared by L to create a 3D metal-organic framework, which possesses a parallelogram channel with diagonal distances of-13.3 × 17.6 A along the b direction. 2 is structurally similar to 1, but has larger diagonal distances of-14.0 × 26.7 A. due to the elongated auxiliary ligand BPDC compared with the BDC ligand in 1. They are both thermally stable and exhibit strong photoluminescence in the visible region.

Hydrothermal Synthesis,Crystal Structure and Magnetic Properties of a Novel Cobalt Complex Based on Biphenyl-3,3',4,4'-tetracarboxylate

A novel cobalt complex,[Co2（bptc）（bix）1.5]（1,H4bptc=3,3＇,4,4＇-biphenyltetra-carboxylic acid,bix = 1,4-bis（imidazol-1-ylmethyl）benzene）,has been hydrothermally prepared and characterized by IR spectroscopy,elemental analysis and single-crystal X-ray diffraction.The crystal is of triclinic system,space group P1 with a=10.770（7）,b=12.245（8）,c=13.514（9）,α=102.829（8）,β=107.734（8）,γ=98.833（9）°,C37H27N6O8Co2,Mr=801.51,V=1607.5（18）3,Dc=1.656g/cm3,F（000）=818,μ=1.100mm-1,Z=2,the final R = 0.0694 and wR = 0.1543 for 3034 observed reflections（I2σ（I））.In the title complex,the two Co（Ⅱ） ions are in different coordination environments with distorted octahedral and trigonal bipyramidal geometries,respectively.The Co atoms are linked together through hexadentate bptc ligands,giving rise to 2D layers which are bridged by the bix ligands into a 3-D supramolecular network.Magnetic susceptibilities of 1 reveal weak antiferromagnetic exchange interactions between the adjacent Co（Ⅱ） ions.

Synthesis and Crystal Structure of 2-Ethoxy-3-n-butyl-benzofuro [2,3-d]pyrimidin-4(3H)-one

The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4（3H）-one （C16H18N2O3, Mr = 286.32） has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167（14）, b = 13.113（1）, c = 8.378（1） A, β = 98.992（2）^o, V = 1488.4（3） A^3, Z = 4, Dc = 1.278, F（000） = 608, μ = 0.089 mm^-1, MoKa radiation （2 = 0.71073）, R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar.

Synthesis,Crystal Structure and Biological Activity of 2-(Anthracen-9-yl)-5-p-tolyl-1,3,4-oxadiazole

A novel compound,2-（anthracen-9-yl）-5-p-tolyl-1,3,4-oxadiazole（C23H16N2O）,has been synthesized by the condensation of 4-methylbenzohydrazide and anthracene-9-carbaldehyde in an ethanol solution with chloramine-T.The compound was characterized by 1H-NMR,13C-NMR,MS and single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P with a = 7.7817（4）,b = 8.8544（5）,c = 12.4726（8） ,β = 92.8520（10）°,Z = 2,V = 826.58（8） 3,Dc = 1.352 g/cm3,Mr = 336.38,λ（MoKα） = 0.71073 ,μ = 0.084 mm-1,F（000） = 352,R = 0.0381 and wR = 0.1099.The dihedral angle between anthracene skeleton and phenyl ring is 64.19°.A total of 6354 unique reflections were collected,of which 3172 with I 〉 2σ（I） were observed.X-ray analysis indicated an offset face-to-face π-π stacking interaction between anthracene skeletons and an offset face-to-face π-π stacking interaction between phenyl ring planes.The novel compound molecules are connected through the offset face-to-face π-π stacking interactions to generate a three-dimensional network.The preliminary bioassay results showed that the novel compound exhibited significant insect growth inhibitory activity against Spodoptera litura Fabricius larvae.