E-pH diagram of ZnS-H_2O system during high pressure leaching of zinc sulfide

The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and different temperatures were drawn through thermodynamical calculation.With the temperature increasing,the stable regions of S and Zn(Ⅱ) in the E-pH diagrams become gradually larger,but the amplification decreases over 150℃.The impacts of leaching parameters,such as temperature,liquid to solid ratio,initial acidic concentration,leaching time,oxygen partial pressure and stirring speed on the leaching rate of Zn(Ⅱ) and conversion rate of S in the single factor of high pressure leaching experiment of ZnS in autoclave,were studied.The leaching residue was examined by X-ray fluorescence(XRF) chemical composition identification and X-ray diffraction(XRD) phase identification,and the content of the leaching solution was tested by inductively coupled plasma-atomic emission spectrometry(ICP).The experimental results indicate that the leaching rate of zinc increases from 60.05% to 97.85% and the conversion rate of sulfur increases from 38.90% to 80.92% with the temperature increasing from 110℃ to 150℃,5:1 of liquid-to-solid ratio,150 g/L of initial acidic concentration,120 min of leaching time,0.8 MPa of oxygen partial pressure,and 480 r/min of stirring speed,which tend to be stable over 150℃.The experimental results correspond with theoretical calculation.

以Spiro-OMeTAD作为空穴传输层的ZnS/SnS太阳能电池模拟研究

硫化亚锡(SnS)因其合适的电学和光学特性而被作为太阳能电池的吸收层进行研究。Spiro-OMeTAD常用作空穴传输层以提高太阳能电池性能。本文采用wxAMPS软件对SnS基太阳能电池ZnS/SnS/Spiro-OMeTAD进行模拟研究。主要研究分析Spiro-OMeTAD空穴传输层对太阳能电池性能的影响,其中包括:开路电压、短路电流密度、填充因子、光电转换效率及量子效率。研究结果表明:在加入Spiro-OMeTAD空穴传输层后,ZnS/SnS/Spiro-OMeTAD太阳能电池的开路电压(V_(OC))增加至0.958 V,短路电流(J_(SC))增加到32.96 mA/cm^(2),填充因子(FF)和光电转换效率(PCE)分别达到了79.26%和25.07%,电池性能取决于电池各层厚度、掺杂浓度、缺陷态密度及工作温度。通过研究表明Spiro-OMeTAD作为空穴传输层,有利于提高太阳能电池的各性能,并且ZnS/SnS/Spiro-OMeTAD是一种十分具有发展潜力的光伏器件结构。

Effect of ammonium sulfate on the formation of zinc sulfide species on hemimorphite surface and its role in sulfidation flotation

Effectively strengthening the surface sulfidation is essential for recovering hemimorphite by froth flotation.In this work,inductively coupled plasma optical emission spectrometer(ICP-OES)measurements,Visual MINTEQ calculation,X-ray photoelectron spectroscopy(XPS)analysis,time of flight secondary ion mass spectrometry(ToF-SIMS)analysis,and micro-flotation experiments were explored to systematically investigate the effect of ammonium sulfate((NH_(4))_(2)SO_(4))on the formation of zinc sulfide species on hemimorphite surface and its role in sulfidation flotation.The results showed that(NH_(4))_(2)SO_(4)exhibited a positive influence on hemimorphite sulfidation flotation.It was ascribed to the number of zinc components in the form of Zn^(2+)and[Zn(NH_(3))_(i)]^(2+)(i=1–4)increased in the flotation system after hemimorphite treatment with(NH_(4))_(2)SO_(4),which was beneficial to its interaction with sulfur species in solution,resulting in a dense and stable zinc sulfide layer generated on the hemimorphite surface.[Zn(NH_(3))_(i)]^(2+)participated in the sulfidation reaction of hemimorphite as a transition state.In addition the sulfidation reaction of hemimorphite was accelerated by(NH_(4))_(2)SO_(4).Thus,(NH_(4))_(2)SO_(4)presents a vital role in promoting the sulfidation of hemimorphite.

Electrodeposition of Zn(O,S)(zinc oxysulfide)thin films:Exploiting its thermodynamic and kinetic processes with incorporation of tartaric acid

Zn（O,S）（zinc oxysulfide） is an important chalcogenide material recently reported to be potentially applied as electrode buffers in thin film solar cells. Both vacuum and solution approaches have enabled the fabrication of Zn（O,S） films. However they either require extreme conditions and high energy consumption for synthesis, or suffer from lack of controllability mainly due to the thermodynamic and kinetic distinction between Zn O and Zn S during film growth. Here we demonstrated an effective electrodeposition route to obtain high-quality Zn（O,S） thin films in a controllable manner. Importantly, tartaric acid was employed as a secondary complexing agent in the electrolyte to improve the film morphology, as well as to adjust other key properties such as composition and absorption. To elucidate the vital role that tartaric acid played, thermodynamic and kinetic processes of electrodeposition was investigated and discussed in detail. The accumulative contribution has shed light on further exploit of Zn（O,S） with tunable properties and optimization of the corresponding electrodeposition process, for the application in thin film solar cells.

不同硫压退火对溅射沉积ZnS薄膜性能的影响

ZnS作为一种宽带隙半导体,以其优异的光电性能近年来受到广泛关注,在太阳能电池、光催化剂以及传感器方面有着广阔的应用前景.本文首先以射频磁控溅射方法沉积了ZnS薄膜,然后在600℃温度和不同硫压下进行退火,通过X射线衍射、扫描电子显微镜、能量散射X射线谱、紫外-可见透射光谱以及慢正电子多普勒展宽谱对ZnS薄膜的晶体结构、表面形貌、晶粒尺寸、成分、透光率以及缺陷进行分析.结果表明:硫气氛后退火能够改善ZnS薄膜结晶性,退火后ZnS薄膜光学带隙为3.43—3.58 eV.当硫压高于0.49 atm(1 atm=1.01×10^(5)Pa)时,ZnS内部硫间隙原子以及表面单质硫降低了薄膜在可见光区的透光率.慢正电子多普勒展宽谱结果还表明,ZnS薄膜的缺陷浓度由表层到内层逐渐降低,薄膜缺陷随着硫压增加而降低.同时,3γ湮没证明了薄膜内部较为致密,硫化会导致薄膜开孔率增加.吸附硫通过内扩散占据了晶体中硫空位缺陷的位置,导致缺陷浓度降低,进而改善了薄膜质量.

具有ZnS负载富羧基PVDF复合膜的制备及乳液分离和光催化染料降解

含大量有机染料的含油废水对环境的污染日益严重。超润湿材料具有特殊的润湿性,在膜分离技术中得到了广泛的应用,其优异的乳液分离性能与特定的表面形貌有关。本研究先通过溶液转化法制备了聚偏氟乙烯/乙烯-co-马来酸酐共聚物(PVDF/PEMA)膜,后依次进行酸碱处理制备出富羧基离子的PVDF复合膜,最后在膜表面原位沉积ZnS微纳米颗粒。制备的复合膜在水中表现出超疏油性,对含植物油的水包油乳液的分离效率达到97%以上。此外,该膜具有自洁性和抗污染性。对亚甲基蓝降解效率高达98%以上,重复5次吸附-降解实验表面该膜具有优异的可重复使用性。因此,该膜在乳液分离和染料降解方面具有潜在的应用前景。

Manipulating Horizontal Zn Deposition with Graphene Interpenetrated Zn Hybrid Foils for Dendrite-Free Aqueous Zinc Ion Batteries

Aqueous zinc ion batteries(ZIBs)with intrinsic safety have great potentials in portable devices,but suffer from limited cycling life mainly caused by serious dendrite growth and unavoidable side reactions of Zn anodes.Herein,graphene interpenetrated Zn(GiZn)hybrid foils are developed for dendrite-free and long-term Zn anodes for high-performance ZIBs.The GiZn anode is prepared by interfacial assembly of reduced graphene oxide(rGO)on the skeletons of zinc foams,followed by mechanical compression into hybrid foils and drying process.The presence of the rGO nanosheets in the GiZn hybrid foils provides abundant zincophilic sites to induce horizontal Zn deposition for Zn metal anodes without the growth of dendrites.Meanwhile,the uniform distribution of rGO nanosheets endows the hybrid foils with superior conductivity and wetting ability with electrolytes for reduced interfacial resistances.As a result,GiZn-based symmetric cells exhibit a small voltage hysteresis of 30.4 mV and remarkable areal capacity of 30 mAh cm^(-2)at 0.5 mA cm^(-2).Further,GiZn anodes also enable the corresponding aqueous Zn||MnO_(2)batteries with high capacity of 168.5 mAh g^(-1)at 8 C,superior to the counterpart with pure Zn foil anodes(72.7 mAh g^(-1)).Therefore,GiZn hybrid foil anodes will shed light on the rational construction of 2D material-interpenetrated Zn hybrid foil anodes for high-performance ZIBs.

Pressure acid leaching of zinc sulfide concentrate

Effects of particle size of the zinc sulfide concentrate,leaching temperature,solid-to-liquid ratio and additive amount on pressure acid leaching process of the zinc sulfide concentrate were studied.The results indicate that the additive can improve the reaction kinetics and the conversion rate.And sulfur can be successfully separated from the zinc sulfide concentrate as elemental sulfur.The reasonable experiment parameters are obtained as follows:the leaching temperature 150℃,oxygen partial pressure 1 MPa,additive amount 1%,solid-to-liquid ratio 1:4,leaching time 2 h,initial sulfuric acid concentration 15%,and particle size less than 44μm.Under the optimum conditions,the leaching rate of the zinc can reach 95%and the reduction rate of the sulfur can reach 90%.

Influence of low-temperature sulfidation on the structure of ZnS thin films

ZnS thin films were prepared by sulfuring zinc thin films at different sulfuration temperatures. The crystal structure,surface morphology, defects, and optical properties of the thin films were characterized by x-ray diffraction(XRD), scanning electron microscopy(SEM), positron annihilation Doppler broadening, and UV-Vis spectrophotometer, respectively.It was found that the(200)-plane preferred orientation of the ZnS thin films changed to(111)-plane with increasing sulfidation temperature. Moreover, a number of large holes were generated at 420?C and eliminated at 440?C. The concentration of defects was lowest when the sulfuration temperature was 440?C. The optical transmission of all samples was maintained at 60%–80% in the wavelength range of 400 nm–800 nm, and the band energy of the ZnS thin films was approximately3.5 e V for all treatment temperatures except 430?C.

Reaction behaviors of Pb and Zn sulfates during reduction roasting of Zn leaching residue and flotation of artificial sulfide minerals

To evaluate the feasibility of recovering Pb and Zn sulfides and Ag-containing minerals from Zn leaching residue by the process of reduction roasting followed by flotation,the reaction behaviors of Pb and Zn sulfates during this process were investigated.Chemical analysis showed that the transformation ratios of PbSO4 and ZnSO4 could reach 65.51%and 52.12%,respectively,after reduction roasting,and the introduction of a sulfidation agent could improve the transformation ratios of these sulfates.scanning electron microscopy-energy dispersive spectroscopy(SEM-EDS)revealed that temperature obviously affects the particle size,crystal growth,and morphology of the artificial Pb and Zn sulfide minerals.Particle size analysis demonstrated that the particle size of the materials increases after roasting.Flotation tests revealed that a flotation concentrate composed of 12.01wt%Pb,27.78wt%Zn,and 6.975×10^(−2)wt%Ag with recoveries of 60.54%,29.24%,and 57.64%,respectively,could be obtained after roasting.

A review of major non-sulfide zinc deposits in Iran

The numerous non-sulfide zinc ore deposits were the historical basis for the development of zinc mining in Iran.They include the Mehdiabad,Irankouh and Angouran world-class deposits,as well as the Zarigan and Haft-har deposits.These deposits were formed by supergene oxidation of primary sulfide minerals during the complex interplay of tectonic uplift,karst development,changes in the level of the water table,and weathering.Zn(Pb)carbonates,Zn-hydrosilicates and associated hydrated phases directly replace the primary ore bodies or fill cavities along fractures related to uplift tectonics.Direct replacement of primary sulfides is accompanied by distal precipitation of zinc non-sulfide minerals in cavities or internal sediments filling.The mineralogy of the non-sulfide mineralization in all six deposits is generally complex and consists of smithsonite,hydrozincite,and hemimorphite as the main economic minerals,accompanied by iron and manganese oxy-hydroxides and residual clays.Commonly,non-sulfide minerals in these deposits consist of two types of ore:red zinc ore(RZO),rich in Zn,Fe,Pb-(As)and white zinc ore(WZO),typically with very high zinc grades but low concentrations of iron and lead.Typical minerals of the RZO are Fe-oxyhydroxides,goethite,hematite,hemimorphite,smithsonite and/or hydrozincite and cerussite.Common minerals of the WZO are smithsonite or hydrozincite and only minor amounts of Fe-oxyhydroxides and hemimorphite.

REE Geochemistry of Sulfides from the Huize Zn-Pb Ore Field, Yunnan Province: Implication for the Sources of Ore-forming Metals

REE abundances in sulfides from the Huize Zn-Pb ore field were determined with the ICPMS after preconcentration. The REE abundances in 26 sulfide samples （including pyrite, galena and sphalerite） are very low, with the ~REE ranging from 1.6×10^-9 to 166.8×10^-9. Their LREE/HREE ratios range from 7.6 to 98, showing LREE enrichment relatively. The JEu values are below 1, indicating that they were deposited from an Eu-depleted and reducing fluid-system. Similar to the ore-hosting carbonate strata, calcite separates from carbonate veinlets filling in the fractures or faults crosscutting the carbonate strata also show clear Eu-depletion. This indicates that the carbonate veinlets and their parent fluid was possibly sourced from the strata and inherited the REE geochemical features of the strata. Therefore, REE-geochemical characteristics of both the sulfides and calcites, which were deposited from an ore-forming hydrothermal system, are similar to those of carbonate strata, and strongly suggest that the ore metals were mainly sourced from carbonate strata.

ZnO_(1–x)S_(x)异质结光催化降解有机染料的综合实验设计

围绕能源和环境催化领域的前沿研究热点,设计了一个科教融合的综合化学实验项目——ZnO_(1-x)S_(x)异质结光催化降解有机染料。该项目以光催化剂的水热合成、结构/形貌表征、性能测试和数据分析为主线,模拟了科学研究的全过程。通过参与该实验项目,学生能够自主探索ZnO_(1-x)S_(x)异质结的组分比例对其结构、光学性质和光催化性能的影响规律,并初步推断异质结界面光生载流子的转移路径。该实验项目训练了学生对多种化学学科知识的理解与综合运用,有助于培养他们的自主创新意识、实践应用能力和批判性思维,教学质量大大提高。

Zn^(2+)掺杂硫化物/氢氧化物异质结构的性能

为提升硫化物的倍率性能和循环稳定性,采用两步电沉积法制备过渡金属硫化物/氢氧化物异质结构复合电极。在碳布上电沉积镍层,改良活性物质与碳布的接触活性;在硫代乙酰胺中添加Zn(NO3)2·7H_(2)O,制备Zn^(2+)掺杂的过渡金属硫化物/氢氧化物异质结构(NCS-Zn-2)。NCS-Zn-2在1 A/g电流下,比电容达到2 703 F/g,在150 A/g高电流下的比电容是1 A/g的40.8%,具有较好的倍率性能。NCS-Zn-2与活性炭组装的工作电压为1.6 V高电压水系非对称超级电容器,在794 W/kg的比功率下,具有79.9 W·h/kg的比能量,以20 A/g电流在0~1.6 V循环20 000次,电容保持率为98.7%。

ZnS/TiO_(2)催化剂光催化CO_(2)的还原性能

利用光催化技术将CO_(2)转化为有用化学品或太阳能燃料是解决能源和环境问题的有效方法之一.通过水热法制备了ZnTi-LDH,并通过0.1 mol·L^(−1)Na_(2)S溶液对其进行硫化处理,制备了不同硫化时间的ZnS/TiO_(2)光催化剂.采用XRD、TEM、UV-vis DRS、化学工作站等方法,详细分析了硫化时间对光催化剂的组成、结构、光吸收性能和电化学质以及光催化H2O还原CO_(2)性能的影响.与ZnTi-LDH相比,硫化处理得到的ZnS/TiO_(2)光催化CO_(2)还原性能均有明显提高,其中ZnS/TiO_(2)/S-1 h的样品具有最高的光催化活性,其CO和H_(2)的产率分别为25.35μmol·(g·h)^(−1)和15.54μmol·(g·h)^(−1),是未硫化样品的4倍和1.5倍.硫化后样品光催化性能的改善可归因于,硫化样品较好的可见光吸收性能、较高的电子空穴分离效率以及其光电子还原能力的提高.

Recent Advances in Aqueous Zn||MnO_(2)Batteries

Recently,rechargeable aqueous zinc-based batteries using manganese oxide as the cathode(e.g.,MnO_(2))have gained attention due to their inherent safety,environmental friendliness,and low cost.Despite their potential,achieving high energy density in Zn||MnO_(2)batteries remains challenging,highlighting the need to understand the electrochemical reaction mechanisms underlying these batteries more deeply and optimize battery components,including electrodes and electrolytes.This review comprehensively summarizes the latest advancements for understanding the electrochemistry reaction mechanisms and designing electrodes and electrolytes for Zn||MnO_(2)batteries in mildly and strongly acidic environments.Furthermore,we highlight the key challenges hindering the extensive application of Zn||MnO_(2)batteries,including high-voltage requirements and areal capacity,and propose innovative solutions to overcome these challenges.We suggest that MnO_(2)/Mn^(2+)conversion in neutral electrolytes is a crucial aspect that needs to be addressed to achieve high-performance Zn||MnO_(2)batteries.These approaches could lead to breakthroughs in the future development of Zn||MnO_(2)batteries,off ering a more sustainable,costeff ective,and high-performance alternative to traditional batteries.

Nucleation and Growth of Zinc Sulfide Nanoparticles in Ultrathin Polymer Films by Layer-by-Layer Polyionic Assemblies

In this work, zinc sulfide (ZnS) nanoparticles were formed by nucleation and growth in ultrathin films of polydiallyldi-methylammonium chloride (PDDA)–polystyrenesulfonate sodium salt (PSS) film produced by the Layer-by-Layer (LbL) deposition technique. Multilayer thin film assemblies, fabricated by sequential adsorption of polyelectrolytes on a quartz substrate, were used as a supramolecular reaction template to study the in-situ nucleation and growth of ZnS nanoparticles. ZnS nanoparticles were nucleated within the polymeric supramolecular structure through cyclic expo-sure to the solutions of Zn(NO3)2 and thiourea. The growth and nucleation of nanoparticles were accomplished by a cyclic repetition of reductive hydrolysis reactions. The growth of a thin film on a flat substrate via LbL was monitored by ultraviolet-visible (UV-Vis) spectroscopy. Analysis of the UV-visible absorption spectra of the films revealed that the nanoparticles grew with increasing number of cycles. The presence of ZnS nanoparticles were verified by transmission electron microscopy (TEM). Selected area electron diffraction (SAED) showed that the ZnS has a cubic spheralite structure.

医用可降解Zn-Sn-Cu合金的力学及腐蚀性能研究

可生物降解锌及其合金具有良好的生物相容性和降解速率,在生物医用材料领域具有广阔的应用前景。但纯锌的力学性能不足,如强度低、可塑性差,限制了其临床应用。在此,采用重力铸造制备了新的三元Zn-3Sn-x Cu(x=0,1,2,3wt%)合金,旨在通过与铜(Cu)的微合金化来获得良好的耐腐蚀性和生物相容性,并提高力学性能。通过金相分析、拉伸试验、显微硬度测试以及电化学和浸泡试验,分析其微观结构、力学性能及耐蚀性能。结果表明,Cu的加入,使得合金具有更高的强度和硬度;体外降解试验表明:Zn-3Sn-x Cu(x=0,1,2,3wt%)合金的降解速率较Zn-3Sn合金有较幅的提升,满足可降解医用材料的标准,有望成为一种新型可降解医用材料。

Structural and Characteristics of Manganese Doped Zinc Sulfide Nanoparticles and Its Antibacterial Effect against Gram-Positive and Gram-Negative Bacteria

The Manganese doped zinc sulfide nanoparticles of the cubic zinc blende structure with the average crystallite size of about 3.56 nm were synthesized using a coprecipitation method using Thioglycolic Acid as an external capping agent for surface modification. The ZnS:Mn2+ nanoparticles of diameter 3.56 nm were manufactured through using inexpensive precursors in an efficient and eco-friendly way. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy are used to examine the structure, morphology and chemical composition of the nanoparticles. The antimicrobial activity of (ZnS:Mn2+) nanocrystals was investigated by measuring the diameter of inhibition zone using well diffusion mechanism versus two various bacterial strains. The technique of microorganism inactivation was considered as sorts-dependent. Bacillus subtilis showed the largest antibacterial sensitivity (35 mm) to ZnS: Mn2+ nanoparticles at a concentration (50 mM) whereas Escherichia coli offered maximum zone of inhibition (20 mm) at the same concentration. In this study, the results indicated that ZnS:Mn2+ nanoparticles were found to have significant antibacterial activity against Gram-negative (E. coli) and Gram-positive (Bacillus subtilis) bacteria.

火焰喷涂纯锌和Zn-Al合金涂层的耐腐蚀性能

在6061-T6铝合金表面制备了火焰喷涂纯锌、Zn-15Al合金和Zn-30Al合金涂层,研究了不同涂层的微观形貌、耐中性盐雾腐蚀性能和电化学性能。结果表明:纯锌、Zn-15Al合金和Zn-30Al合金涂层截面结构致密,孔隙率依次降低,与基体呈机械结合;经中性盐雾腐蚀后,纯锌、Zn-15Al合金与Zn-30Al合金涂层的腐蚀质量增加和腐蚀速率依次减小,Zn-30Al合金涂层表现出最好的耐中性盐雾腐蚀性;在人工海水溶液中,3种涂层的开路电位均低于铝合金基体,可以对基体进行牺牲阳极保护;相比纯锌涂层,Zn-15Al合金和Zn-30Al合金涂层的自腐蚀电流密度更小,自腐蚀电位更高,腐蚀速率更小,腐蚀倾向更低;随着浸泡腐蚀时间延长,Zn-15Al合金涂层的耐腐蚀性能无显著变化,Zn-30Al合金涂层的耐腐蚀性能逐渐增强。Zn-30Al合金涂层表现出最好的耐电化学腐蚀性。