Deciphering the potassium storage phase conversion mechanism of phosphorus by combined solid-state NMR spectroscopy and density functional theory calculations

Phosphorus is the potential anode material for emerging potassium-ion batteries(PIBs)owing to the highest specific capacity and relatively low operation plateau.However,the reversible delivered capacities of phosphorus-based anodes,in reality,are far from the theoretical capacity corresponding to the formation of K3P alloy.And,their underlying potassium storage mechanisms remain poorly understood.To address this issue,for the first time,we perform high-resolution solid-state31P NMR combined with XRD measurements,and density functional theory calculations to yield a systemic quantitative understanding of(de)potassiation reaction mechanism of phosphorus anode.We explicitly reveal a previously unknown asymmetrical nanocrystalline-to-amorphous transition process via rP←→(K_(3)P_(11),K_(3)P_(7),beta-K_(4)P_(6))←→(alpha-K4P6)←→(K_(1-x)P,KP,K_(4-x)P3,K_(1+x)P)←→(amorphous K4P3,amorphous K3P)that are proceed along with the electrochemical potassiation/depotassiation processes.Additionally,the corresponding KP alloys intermediates,such as the amorphous phases of K_(4)P_(3),K_(3)P,and the nonstoichiometric phases of“K_(1-x)P”,“K_(1+x)P”,“K_(4-x)P_(3)”are experimentally detected,which indicating various complicated K-P alloy species are coexisted and evolved with the sluggish electrochemical reaction kinetics,resulting in lower capacity of phosphorus-based anodes.Our findings offer some insights into the specific multi-phase evolution mechanism of alloying anodes that may be generally involved in conversion-type electrode materials for PIBs.

The adsorptive properties of UiO-66 towards organic dyes: A record adsorption capacity for the anionic dye Alizarin Red S.

In order to decisively determine the adsorption selectivity of zirconium MOF(UiO-66) towards anionic versus cationic species, the adsorptive removal of the anionic dyes(Alizarin Red S.(ARS), Eosin(E), Fuchsin Acid(FA)and Methyl Orange(MO)) and the cationic dyes(Neutral Red(NR), Fuchsin Basic(FB), Methylene Blue(MB),and Safranine T(ST)) has been evaluated. The results clearly reveal a significant selectivity towards anionic dyes. Such an observation agrees with a plethora of reports of UiO-66 superior affinity towards other anionic species(Floride, PO_4^(3-), Diclofenac sodium, Methylchlorophenoxy-propionic acid, Phenols, CrO_4^(2-), SeO_3^(2-), and AsO_4^-). The adsorption process of ARS as an example has been optimized using the central composite design(CCD). The resultant statistical model indicates a crucial effect of both pH and sorbent mass. The optimum conditions were determined to be initial dye concentration 11.82 mg.L^(-1), adsorbent amount 0.0248 g, shaking time of 36 min and pH 2. The adsorption process proceeds via pseudo-second order kinetics(R^2= 0.999). The equilibrium data were fit to Langmuir and Tempkin models(R^2= 0.999 and 0.997 respectively). The results reveal an exceptional removal for the anionic dye(Alizarin Red S.) with a record adsorption capacity of400 mg·g^(-1). The significantly high adsorption capacity of UiO-66 towards ARS adds further evidence to the recently reported exceptional performance of MOFs in pollutants removal from water.

Synthesis and Application of Oil-Soluble Red Dyes Derived from p-n-Alkyl Aniline

In this study, the azo red dyes derived from p-n-alkyl aniline by the introduction of different alkyl groups having high solubility in dodecane were synthesized. Results indicated that the elementary properties of red oil inks were 1) non-polarity;2) low viscosity (<3.0 cps);3) specified surface tension (<30 mN/m);4) intensity of visible absorption covering 480 - 540 nm;5) hue close to standard red (CIE(x, y) = 0.67, 0.33). We can conclude that these azo red dyes are applicable for electrowetting displays.

Ecological toxicity of reactive X-3B red dye and cadmium acting on wheat (Triticum aestivum)

Ecological toxicity of reactive X\|3B red dye and cadmium in both their single form and their combined form on wheat was studied using the experimental method of seed and root exposure. The single factor exposure indicated that the inhibitory rate of wheat root elongation was significantly increased with the increase in the concentration of the dye in the cultural solution, although seed germination of wheat was not sensitive to the dye. The toxicity of cadmium was greatly higher than that of the dye, but low concentration cadmium (<40 mg/L) could promote the germination of wheat seed. Interactive effects of the dye and cadmium on wheat were complicated. There was no significant correlation between the inhibitory rate of seed germination and the concentrations of the dye and cadmium. Low concentration cadmium could strengthen the toxicity of the dye acting on root elongation. On the contrary, high concentration cadmium could weaken the toxicity of the dye acting on root elongation.

Adsorption behavior of Azo Dye C. I. Acid Red 14 in aqueous solution on surface soils

Azo dyes have received considerable attention because of their association with various human health problems. The aim of the investigation is to determine the adsorption behavior ofazo dyes in aqueous solution on DG06, GSE17200, and GSE17201 soils using C. I. Acid Red 14 （AR14） as example. The experimental results indicate that the Freundlich model expresses the adsorption isotherm better than the Langmuir model and the pseudo-second-order model achieves adsorption of AR14 on the three soils well. Based on the pseudo-second-order model, the adsorption thermodynamic of AR14 on DG06 soil have been studied and the thermodynamics parameter of AGO is determined and AGO value shows the adsorption process of AR14 on DG06 is mainly physical in nature. Furthermore, the effects of temperature, pH and salinity （NaC1） on adsorption have been investigated. The decrease in pH or the increase in salinity enhances the adsorption of AR14 by DG06, GSE17200, and GSE17201.

Effects of adsorption interferents on removal of Reactive Red 195 dye in wastewater by chitosan

Reactive Red 195, which is an azoic anionic dye characterized by the presence of five sulfonic groups and one azoic group, is efficiently removed using chitosan. The increasing chitosan dose had a dramatic positive impact on the achieved color removal, there was approximately a linear relationship between chitosan dose and color removal of dye before color removal reach maximum. Also, the increase of dye concentration led to the increase of chitosan dosage in order to get the same color remova l.92 mg/L of chitosan dosage was sufficient to achieve complete remove of dye at initial concentration of dye at 200 mg/L. For the higher concentrations of dye, high dosages were necessary to reach complete color removal. On the other hand, the use of adsorption interferents（Fe^2＋ , Na^＋ , HCO3^- and others） can be interesting, addition of ions had effect on the color removal of Reactive Red 195. Comparing with blank, addition of chemical species approximately decreased the color removal except Na^＋ and combination of Fe^2＋ ＋ HCO3^- . However, comparing with Fe^2＋ alone and HCO3^- alone, combination of Fe^2＋ ＋ HCO3^- increased the color removal.

Synthesis and characterization of carboxymethyl cellulose/organic montmorillonite nanocomposites and its adsorption behavior for Congo Red dye

A series of carboxymethyl cellulose/organic montmorillonite （CMC/OMMT） nanocomposites with different weight ratios of carboxymethyl cellulose （CMC） to organic montmorillonite （OMMT） were synthesized under different conditions. The nanocomposites were characterized by the Fourier transform infrared （FT-IR） spectrophotometer, X-ray diffraction （XRD） method, transmission electron microscope （TEM）, scanning electron microscope （SEM）, and thermal gravimetric （TG） analysis. The results showed that the introduction of CMC may have different influences on the physico-chemical properties of OMMT and intercalated-exfoliated nanostructures were formed in the nanocomposites. The effects of different reaction conditions on the adsorption capacity of samples for Congo Red （CR） dye were investigated by controlling the amount ofhexadecyl trimethyl ammonium bromide （CTAB）, the weight ratio of CMC to OMMT, the reaction time, and the reaction temperature. Results from the adsorption experiment showed that the adsorption capacity of the nanocomposites can reach 171.37 rag/g, with the amount of CTAB being 1.0 cation exchange capacity （CEC） of MMT, the weight ratio of CMC to OMMT being l：l, the reaction time being 6 h, and the reaction temperature being 60~C. The CMC/OMMT nanocomposite can be used as a potential adsorbent to remove CR dye from an aqueous solution.

Synthesis and Investigation of Phenol Red Dye Doped Polymer Films

The optical properties of the pure polymer film and polymer films doped with Phenol Red dye at different concentrations were investigated. The films were prepared using the casting technique. Poly (methyl-methacrylate) (PMMA) polymer was doped with the Phenol Red dye dissolved in a mixture of chloroform and little quantity of methanol, used as suitable solvent for both the dye and the polymer. The spectral absorption measurements of these films were carried out at different dye concentrations using UV-Vis double-beam spectrophotometer in the wavelength range 300 - 800 nm. The optical parameters of the prepared Phenol Red dye doped polymer films, absorption coefficient (α), extinction coefficient (κ), refractive index (n), optical and electrical conductivities (σopt and σelect), and optical energy band gap (Eg), were determined. The results showed that the Phenol Red dye doped polymer film is a good candidate for photonic applications such as, solar cells, optical sensors, and other photonic devices.

Enhancement of modulation depth of an all-optical switch using an azo dye-ethyl red film

The polymethyl methacrylate （PMMA） film doped with an azo dye ethyl-red （ER） film is employed to demonstrate the properties of an all-optical switch by its photoinduced dichroism and birefringence. We show how to enhance remarkably the modulation depth of all-optical switches almost to 100% by using two linear polarization beams： one beam is inclined at 45° with respect to the probing beam and serves as a pumping beam, and the other beam is perpendicular to the probing beam and used as an erasing beam. Furthermore, a maximum-to-minimum output intensity ratio of 2000：1 is achieved in experiment, which is very useful and important for optical storages and image displays.

Detailed analysis of ultrathin fluorescent red dye interlayer for organic photovoltaic cells

The influence of an ultrathin 4-（dicyanomethylene）-2-t-butyl-6-（1,1,7,7-tetramethyljulolidyl-9-enyl）-4H-pyran （DCJTB） fluorescent dye layer at donor/acceptor heterojunction on the performance of small-molecule organic photovoltaic （OPV） cell is studied. The structure of OPV cell is of indium-tin oxide （ITO）/copper phthalocyanine （CuPc）/DCJTB/fullerene （C60）/bathophenantbroline （Bphen）/Ag. The results show that open circuit voltage （Voc） increases to 0.57 V as the film thickness of DCJTB layer increases from 0.2 to 2.0 nm. By using an equivalent circuit model, the enhancement of VOC is found to be attributed to the reduced reverse saturation current density （Js） which is due to the lower highest occupied molecular orbital （HOMO） level in DCJTB than that in CuPc. Also, the short circuit current density （JSC） is affected when the DCJTB layer becomes thicker, resulting from the high series resistance RsA due to the low charge carrier mobility of fluorescent red dye.

Dyeing Thermodynamics and Supramolecular Structure of Lac Red on Protein Fibers

The dyeing temperature of natural dye lac red on two kinds of natural protein fibers was studied, and the interaction between dyestuff and fiber was discussed through thermodynamic study and density functional theory (DFT) calculation. The optimum temperature for lac red dyed silk was 60˚C and wool showed a better response at 90˚C. The thermodynamics study revealed good Nernst isotherm and Freundlich adsorption models respectively, and the lac dye adsorption processes were both spontaneous and exothermic. The potential interaction of Laccaic acid A with the external environment by electrostatic potential and atomic charge distribution was first explored. With molecular simulation, Laccaic acid A and glycine composed 8 stable complexes. Then, typical hydrogen bonds, bond length, and binding energy, etc. were analyzed. The results revealed lac red on silk and wool fabric mainly depended on the weak hydrogen bonds and van der Waals force which determined the low dye fastness.

Dyeing PET Textile with C.I.Disperse Red 60 and C.I. Disperse Orange 25 in Supercritical CO_2

For a better understanding of the feasibility of supercritical fluid dyeing(SFD)and more available information for the process development,the experiments of dyeing PET textile with C.I.disperse red 60(anthraquinone type)and C.I.disperse orange 25(azo type)in supercritical CO2 were carried out with a high-pressure dyeing apparatus at temperatures from 80 to 130℃ and pressure up to 31 MPa.The effect of operating conditions on color yield(K/S)was investigated in SFD experiment,and the optimum operating conditions for the above two disperse dyes were obtained as follows:the temperature 120℃,the pressure 25 MPa and the dyeing time 100 min.As compared with SFD,the conventional water dyeing(CWD)was carried out with the same dyes and textile.The results show that the better fastness,levelness and apparent color can be achieved in SFD and the SFD process has many significant advantages over the CWD process.

Spectroscopic and calorimetric studies of congo red dye-amyloid peptide complexes

Thermodynamic properties of complexes of Con ?go Red (CR) dye with amyloid ? (A?) peptides were studied by both absorption spectroscopy and isothermal titration calorimetry (ITC). Based on the absorption spectrum for the formation of CRAβ complexes in phosphate buffered saline solution (pH 7.4), van’t Hoff plots over a temperature range of 10oC to 70oC were created for CRAβ140, Aβ1228, and Aβ142. The plot for CR Aβ1228 complex showed a relatively linear feature within the given temperature range with ?H = –10.1 ?0.6 kJ/mol and ?S = + 0.128 ? 0.002 kJ/(mol K). However, the plot for CRAβ140 and CRAβ142 complexes exhibited two distinct linear regions with opposite slopes centered at a specific temperature, Ts, which was 54.7 ? 0.2℃ and 34.8 ? 0.2℃, respectively. The ITC experiments conducted at 25℃in water exhibited quite a different situation from the above mentioned spectroscopic approach. The ITC studies yielded a ?H of –85.3 ? 0.2 kJ/mol for the CRAβ1228 complex with negative entropy change –0.152 kJ/mol K). For CRAβ140, the ITC studies indicated the presence of two binding sites with ?H1 = –81.8 ? 0.3 kJ/mol and ?H2 = –119.5 ? 0.2 kJ/mol with K1 = 5.5 ? 0.7 ? 106 M1 and K2 = 6.9 ? 2.4 ? 108 M1, respectively. These binding constants are consistent with the model suggested by several studies. Both binding sites showed negative entropy changes suggesting that the formation of the complex is enthalpically driven. The disagreement in thermochemical values between two different methods confirmed that the enthalpy and entropy are heavily dependent on temperature and buffer/salt environment, and may involve inherently different reaction paths.

包覆交联法提升玫瑰茄红上染真丝织物色牢度的应用

文章以甲基丙烯酸甲酯、丙烯酸丁酯、2-羟基乙基甲基丙烯酸酯和甲基丙烯酰氧丙基三(三甲基硅氧烷基)硅烷为原料,合成了聚丙烯酸酯类高分子,再将整理后的织物浸于戊二醛溶液中,以达到化学接枝交联的目的,并将其作为纤维包覆材料应用于天然玫瑰茄红色素染色的真丝织物。实验结果表明:整理后真丝织物的色牢度明显提升,湿摩色牢度从2~3级提升到4级,皂洗色牢度从1~2级提到3~4级,并且整理后织物表现出较好的防水效果,水接触角从接近0°提到125°;机械性能显著改善,断裂强度从8.73 MPa提高到26.37 MPa。

海藻酸钠固定漆酶复合淀粉处理模拟印染废水的应用

采用固定漆酶的海藻酸钠-钙离子交联水凝胶球与阳离子淀粉按质量比1∶1形成新型复合吸附剂,用于对模拟刚果红染料废水的研究。考察如吸附剂投加量、反应时间、pH值等条件对模拟印染废水吸附效果的影响。结果表明,在体积50 mL、转速125 r·min^(-1)的条件下,吸附剂用量为0.6 g、吸附时间30 min、pH值在6~7、反应温度为30℃、刚果红溶液初始浓度为100 mg·L^(-1),脱色率达到96.11%,吸附量为164.2 mg·g^(-1)。对比Freundlich吸附等温方程(R^(2)=0.9899)和Langmuir吸附等温方程(R^(2)=0.9982),表明此处理过程等温拟合模型更符合Langmuir吸附模型,为单层吸附。

沸石咪唑酯骨架-8的制备及其对刚果红的吸附性能

为制备印染废水的吸附材料,以六水合硝酸锌和2-甲基咪唑为原材料,以去离子水作溶剂,采用水溶剂法制备沸石咪唑酯骨架-8(ZIF-8)材料。借助扫描电子显微镜、红外光谱仪、X射线衍射仪等探究ZIF-8材料的结构,测试其对阴离子刚果红染料的吸附性能,并分析其吸附机制。结果表明:ZIF-8颗粒大小均匀,表面光滑,呈多面体结构;其热裂解温度为258℃,具有良好的热稳定性;ZIF-8对刚果红的吸附更符合准二级动力学模型和Langmuir吸附等温线模型,即以化学吸附为主且吸附位点等效;吸附过程为自发进行的放热反应,低温有利于吸附;在温度为20℃、pH值为7的条件下,ZIF-8对95 mg/L的刚果红溶液的吸附效果最佳,吸附量可达671.41 mg/g。

改性蚕丝织物的胭脂虫红染色工艺探析

为使胭脂虫红上染蚕丝织物效果好,采用壳聚糖季铵盐(HACC)对蚕丝织物改性后,用胭脂虫红色素直接染色,探讨改性工艺。研究表明,最佳改性工艺条件为改性温度70℃,改性时间40 min,pH=5,HACC质量浓度4%。胭脂虫红对改性蚕丝织物进行直接染色,得出优化的染色工艺条件为染色温度80℃,染色时间40min,pH=7,染液质量浓度6%。在最佳的工艺条件下,对未改性及改性蚕丝织物进行直接染色和后媒染,用环保的氯化镧稀土为媒染剂,对染色织物的染色性能、色牢度进行测试。结果表明,HACC改性试样经过后媒染法染色,其染色性能、色牢度最好,对生态染整技术发展提供积极的意义。

桑叶茶与小叶紫檀对汉麻纤维套染性能的研究

为扩展天然染料染色的色谱范围,采用桑叶茶和小叶紫檀对汉麻纤维进行套染,分析了桑叶茶染液的质量分数、媒染剂的质量分数、小叶紫檀染液的质量分数对套染汉麻纤维K/S值的影响,以及套染后汉麻纤维的耐摩擦色牢度、耐汗渍色牢度和耐皂洗色牢度。结果表明,桑叶茶与小叶紫檀套染的汉麻纤维可以获得颜色较深的紫红色。综合分析正交试验和单因素试验结果,得到桑叶茶与小叶紫檀对汉麻纤维套染的优化工艺条件如下:桑叶茶染液质量分数60%,媒染剂质量分数10%,小叶紫檀染液质量分数100%。在该条件下所套染汉麻纤维的耐摩擦色牢度和耐汗渍色牢度符合国家服用性能标准,耐皂洗色牢度有待提高。

活性赤泥-聚吡咯复合材料对活性黄-145染料的吸附研究

染料是一种结构复杂、具有剧毒的有机化合物,对人体毒害作用大。本研究制备了一种基于活性赤泥(activated red mud,ARM)和聚合吡咯(polypyrrole,PPy)的吸附剂,并应用于水溶液中染料的吸附脱除。通过吸附实验研究了溶液pH、吸附剂种类、吸附时间、添加量和染料初始浓度对吸附过程的影响,并对ARM-PPy复合材料进行分析表征,阐明了活性黄染料-145(RYD-145)的吸附作用机制。RYD-145在ARM-PPy上的吸附过程与三种吸附等温线关联极好(R2>0.99),其中Langmuir吸附最合适。根据Langmuir吸附模型的拟合结果,RYD-145的最大吸附量是442.5 mg/g。热力学研究表明,RYD-145分子在ARM-PPy的吸附过程中,焓变(ΔH)和熵变(ΔS)均增加,这表明该过程为吸热过程,且表面RYD-145分子排列具有随机性。研究表明,ARM-PPy具有高效处理阴离子和阳离子染料污染废水的能力,且具有较好的成本效益。

双羟基染料改性有色水性聚氨酯的制备与性能

为了探究双羟基染料不同引入方式对水性聚氨酯(WPU)乳液及其成膜性能的影响,采用异佛尔酮二异氰酸酯、聚四氢呋喃(PTMG)、2,2-二羟甲基丙酸和1,4-丁二醇(BDO)合成了WPU乳液。将酸性红87作为扩链剂部分替代BDO制备了有色化学共聚聚氨酯(ARWPUA-1~3)乳液;将酸性红87作为软段部分替代PTMG制备了有色化学共聚聚氨酯(ARWPUB-1~3)乳液;将酸性红87与WPU共混制备了WPU/AR。采用FTIR、1HNMR和UV-Vis对样品的结构进行了表征;考察了不同有色WPU的贮存稳定性、耐溶剂性、颜色特征值、耐干/湿摩擦色牢度以及力学性能,并对其进行了分子动力学模拟。结果表明,由n(酸性红87)∶n(BDO)=1∶4制备的ARWPUA-2具有优异的贮存稳定性;在不同溶剂中均不会发生溶解脱色现象;具有良好的耐干/湿摩擦色牢度和较高的力学性能,其拉伸强度22.6MPa,断裂伸长率为810%。