In-situ interfacial passivation and self-adaptability synergistically stabilizing all-solid-state lithium metal batteries

The function of solid electrolytes and the composition of solid electrolyte interphase(SEI)are highly significant for inhibiting the growth of Li dendrites.Herein,we report an in-situ interfacial passivation combined with self-adaptability strategy to reinforce Li_(0.33)La_(0.557)TiO_(3)(LLTO)-based solid-state batteries.Specifically,a functional SEI enriched with LiF/Li_(3)PO_(4) is formed by in-situ electrochemical conversion,which is greatly beneficial to improving interface compatibility and enhancing ion transport.While the polarized dielectric BaTiO_(3)-polyamic acid(BTO-PAA,BP)film greatly improves the Li-ion transport kinetics and homogenizes the Li deposition.As expected,the resulting electrolyte offers considerable ionic conductivity at room temperature(4.3 x 10~(-4)S cm^(-1))and appreciable electrochemical decomposition voltage(5.23 V)after electrochemical passivation.For Li-LiFePO_(4) batteries,it shows a high specific capacity of 153 mA h g^(-1)at 0.2C after 100 cycles and a long-term durability of 115 mA h g^(-1)at 1.0 C after 800 cycles.Additionally,a stable Li plating/stripping can be achieved for more than 900 h at 0.5 mA cm^(-2).The stabilization mechanisms are elucidated by ex-situ XRD,ex-situ XPS,and ex-situ FTIR techniques,and the corresponding results reveal that the interfacial passivation combined with polarization effect is an effective strategy for improving the electrochemical performance.The present study provides a deeper insight into the dynamic adjustment of electrode-electrolyte interfacial for solid-state lithium batteries.

Synergistic defect passivation and strain compensation toward efficient and stable perovskite solar cells

Rational interface engineering is essential for minimizing interfacial nonradiative recombination losses and enhancing device performance.Herein,we report the use of bidentate diphenoxybenzene(DPOB)isomers as surface modifiers for perovskite films.The DPOB molecules,which contain two oxygen(O)atoms,chemically bond with undercoordinated Pb^(2+) on the surface of perovskite films,resulting in compression of the perovskite lattice.This chemical interaction,along with physical regulations,leads to the formation of high-quality perovskite films with compressive strain and fewer defects.This compressive strain-induced band bending promotes hole extraction and transport,while inhibiting charge recombination at the interfaces.Furthermore,the addition of DPOB will reduce the zero-dimensional(OD) Cs_4PbBr_6 phase and produce the two-dimensional(2D) CsPb_(2)Br_5 phase,which is also conducive to the improvement of device performance.Ultimately,the resulting perovskite films,which are strain-released and defect-passivated,exhibit exceptional device efficiency,reaching 10.87% for carbon-based CsPbBr_(3) device,14.86% for carbon-based CsPbI_(2)Br device,22,02% for FA_(0.97)Cs_(0.03)PbI_(3) device,respectively.Moreover,the unencapsulated CsPbBr_(3) PSC exhibits excellent stability under persistent exposure to humidity(80%) and heat(80℃) for over 50 days.

Nonlinear Doping, Chemical Passivation and Photoluminescence Mechanism in Water-Soluble Silicon Quantum Dots by Mechanochemical Synthesis

A series of boron- and phosphorus-doped silicon wafers are used to prepare a series of doped silicon nanocrystals （nc-Si） by high-energy ball milling with carboxylic acid-terminated surface. The sizes of the nc-Si samples are demonstrated to be 〈 S nm. The doping levels of the nc-Si are found to be nonlinearly dependent on the original doping level of the wafers by x-ray photoelectron spectroscopy measurement. It is found that the nonlinear doping process will lead to the nonlinear chemical passivation and photoluminescence （I3L） intensity evolution. The doping, chemical passivation and PL mechanisms of the doped nc-Si samples prepared by mechanochemical synthesis are analyzed in detail.

In-situ Chemical Age of the Sandstone-hosted Uranium Deposit in Ningdong Area on the Western Margin of the Ordos Basin, North China

Objective The Ordos Basin located in the westem part of the North China Craton bears various energy resources such as oil, gas, coal and uranium. It is one of the richest uranium-bearing basins in China. Since the discovery of the large-scale Dongsheng, Hangjinqi and Daying uranium deposits in the north of the Ordos Basin, a new breakthrough of uranium exploration has been achieved in the Ningdong area （eastern Ningxia） on the western margin of the Ordos Basin （WMOB） in the past two years （Wang Feifei et al., 2017）.

In-situ wafer bowing measurements of GaN grown on Si(111) substrate by reflectivity mapping in metal organic chemical vapor deposition system

In this work, the wafer bowing during growth can be in-situ measured by a reflectivity mapping method in the 3×2 Thomas Swan close coupled showerhead metal organic chemical vapor deposition（MOCVD） system. The reflectivity mapping method is usually used to measure the film thickness and growth rate. The wafer bowing caused by stresses（tensile and compressive） during the epitaxial growth leads to a temperature variation at different positions on the wafer, and the lower growth temperature leads to a faster growth rate and vice versa. Therefore, the wafer bowing can be measured by analyzing the discrepancy of growth rates at different positions on the wafer. Furthermore, the wafer bowings were confirmed by the ex-situ wafer bowing measurement. High-resistivity and low-resistivity Si substrates were used for epitaxial growth. In comparison with low-resistivity Si substrate, Ga N grown on high-resistivity substrate shows a larger wafer bowing caused by the highly compressive stress introduced by compositionally graded Al Ga N buffer layer. This transition of wafer bowing can be clearly in-situ measured by using the reflectivity mapping method.

<i>In-Situ</i>Monitoring of Chemical Vapor Deposition from Trichlorosilane Gas and Monomethylsilane Gas Using Langasite Crystal Microbalance

Using the langasite crystal microbalance (LCM), the trends in film thickness produced by means of the chemical vapor deposition using trichlorosilane gas, monomethylsilane gas and their mixed gas were observed at 600?C and evaluated by comparison with the information from a transmission electron microscope (TEM). The crystalline silicon film thickness from trichlorosilane gas was comparable to that of an amorphous silicon carbide film from monomethylsilane gas. The film obtained from the gas mixture was amorphous and was the thinnest in this study. Because the thickness trend obtained by the LCM agreed with that by the TEM, the LCM is shown to be a convenient evaluation tool for the behavior of various film deposition.

Electrochemical characteristic of chemical-mechanical polishing of copper with oxide passive film

Electrochemical behavior of chemical mechanical polishing of copper with oxide passive film was studied by electrochemical measurement technologies. Dependences of polarization curves and electrochemical parameters, the rate of formation or removal of passive film of copper on film modifier KClO 3 were investigated. The rules of dependences of corrosion potentials and corrosion current densities on polishing pressure and rotation rate were obtained. It is discovered that the rates of formation and removal of passive film of copper are enhanced, while the polishing pressure and rotation rate are reduced. The experiments show that the CMP processes decrease Tafel slope, increase electron transfer coefficient of anode reaction and decrease the activation energy of corrosion reaction of copper, thereby the corrosion processes are accelerated. The results indicate that CMP slurry recipe, which is composed of NaAc NaOH medium, using KClO 3 as passive film modifier and nano sized γ Al 2O 3 as abrasive, is feasible and reasonable. The technological conditions are 100 r/min, 16 kPa.

Chemical leaching mechanism of chalcopyrite with difference mineralization

This paper presents the effect of mineralization on chalcopyrite chemical leaching in very simple H2SO4 solution systems at pH 1.0, with 5 % chalcopyrite con- centrate at 65 ~C. The copper extractions after 12 days leaching of marine volcanic and porphyry chalcopyrite were 85.7 and 66.6 %, respectively. It was found that sulphur element formed on the surface of two samples as a result of XRD and SEM-EDAX, which was very porous that did not inhibit chemical leaching reaction. Meanwhile, （Cu, Fe）12As4S13 formed on the surface of porphyry type chalcopyrite, which may cause low leaching ratio of por- phyry type chalcopyrite as passivation. （Cu, Fe）12As4S13 may be one kind of the polysulphide compounds.

Geochemical characteristics of Holocene sediments from Chuadanga district, Bangladesh: Implications for weathering, climate, redox conditions, provenance and tectonic setting

The present research deals with the geochemical characteristics of the Holocene sediments from Alamdanga area, Chuadanga district, Bangladesh. Main goals of the study are to delineate source rock characteristics, degree of chemical weathering and sorting processes and behavior of redox conditions during deposition of the sediments. Geochemical characteristics of the sediments show comparatively a wide variation in accordance with stratigraphy in their major element contents(e.g. Si O2 69.46–82.13, Al2O3 2.28–8.88 in wt%), reflecting the distinctive provenance and in part an unstable period in terms of tectonic activity. Geochemical classification of the sediments shows mostly sub-arkose with few sub-litharenites. Some major and trace elements display comprehensible correlation with Al2O3 confirming their possible hydraulic fractionation. The chemical index of alteration(CIA*), W* index, index of compositional variability(ICV), plagioclase index of alteration(PIA*) values and the ratio of Si O2/Al2O3, suggest low degrees of chemical weathering in the source areas as well as immature to moderately mature the sediments. The sediments suggest semi-arid climatic trends within oxic deltaic depositional conditions during the Holocene, at 3–12 ka. Whole rock geochemistry and discrimination diagrams demonstrate the continental signature derivatives, which might have been derived from the felsic to intermediate igneous rocks(granitic plutonic rocks) as well as from quartzose sedimentary/metamorphic provenance. These typical sources are present in a vast region of the Himalayan belt and catchment areas of Ganges. The tectonic setting of the sediments demarcates typically passive margin with slightly continental arc system.

Surface passivation in n-type silicon and its application in silicon drift detector

Based on the surface passivation of n-type silicon in a silicon drift detector(SDD), we propose a new passivation structure of SiO2/Al2O3/SiO2 passivation stacks. Since the SiO2 formed by the nitric-acid-oxidation-of-silicon(NAOS)method has good compactness and simple process, the first layer film is formed by the NAOS method. The Al2O3 film is also introduced into the passivation stacks owing to exceptional advantages such as good interface characteristic and simple process. In addition, for requirements of thickness and deposition temperature, the third layer of the SiO2 film is deposited by plasma enhanced chemical vapor deposition(PECVD). The deposition of the SiO2 film by PECVD is a low-temperature process and has a high deposition rate, which causes little damage to the device and makes the SiO2 film very suitable for serving as the third passivation layer. The passivation approach of stacks can saturate dangling bonds at the interface between stacks and the silicon substrate, and provide positive charge to optimize the field passivation of the n-type substrate.The passivation method ultimately achieves a good combination of chemical and field passivations. Experimental results show that with the passivation structure of SiO2/Al2O3/SiO2, the final minority carrier lifetime reaches 5223 μs at injection of 5×10^(15) cm^(-3). When it is applied to the passivation of SDD, the leakage current is reduced to the order of nA.

利用电化学和显色检测法分级评估316L不锈钢钝化膜完整性

针对核电和航天工程不锈钢设备服役在高温高盐海洋环境中钝化和损伤的质检评估,提出显色检测图像分析钝化膜完整性分级的方法。以不同钝化及其损伤状态的316L不锈钢为研究对象,通过显色检测的红色色度图像分析与电化学腐蚀行为检测,建立显色色度与耐蚀性的关系,并获得分级范围。结果表明,显色色度随钝化膜损伤程度增加而增大,随自钝化时间的延长而减小;二次局部损伤在直方图中具有双峰特征;色度百分比和面积百分比呈现双对数线性二阶段特征;动电位极化和阻抗表明,点蚀电位和界面反应阻抗随损伤程度的增加而减小;耐蚀性随显色色度的增加而下降;最终获得了316L不锈钢钝化膜完整性的三个色度等级范围。这可为不锈钢钝化膜质检分级评估提供理论基础。

In-situ homogeneous synthesis of carbon nanotubes on aluminum matrix and properties of their composites

Using nickel catalyst supported on aluminum powders, carbon nanotubes （CNTs） were successfully synthesized in aluminum powders by in-situ chemical vapor deposition at 650 ℃. Structural characterization revealed that the as-grown CNTs possessed higher graphitization degree and straight graphite shell. By this approach, more homogeneous dispersion of CNTs in aluminum powders was achieved compared with the traditional mechanical mixture methods. Using the in-situ synthesized CNTs/Al composite powders and powder metallurgy process, CNTs/Al bulk composites were prepared. Performance testing showed that the mechanical properties and dimensional stability of the composites were improved obviously, which was attributed to the superior dispersion of CNTs in aluminum matrix and the strong interfacial bonding between CNTs and matrix.

脂质体的制备方法及应用的研究进展

目的综述脂质体的制备方法及应用的研究进展,旨在为脂质体的进一步研究与开发新功能提供思路。方法查阅近年来国内外关于脂质体研究的相关文献,并对其进行整理、归纳与总结。结果脂质体作为近几十年发现的一种高效载体,可由人工合成的磷脂化合物来制备,且制备方法日益完善,可根据药物的不同特性对脂质体进行结构修饰,在医药、基因工程、食品、化妆品等领域起着越来越重要的作用。结论脂质体在药物治疗及生活中有着重要的研究意义与应用前景。

Influences of chemical reactions on polysulfide reduction reaction process on promotor surface in Li-S batteries

Polar promotors have been proven effective in catalyzing the polysulfide(PS)reduction reaction(PSRR)process in lithium-sulfur(Li-S)batteries.However,the promotor surface tends to be poisoned due to the accumulation of insoluble discharging products of lithium disulfide(Li_(2)S_(2))and lithium sulfide(Li_(2)S)during Li-S battery operation.Herein,we investigate the detailed PSRR mechanism on the surface of manganese sulfides(MnS)as a representative promoter by performing in-situ Raman mapping measurements.The catalytic ability of MnS enables thorough electrochemical reduction of PSs to Li_(2)S_(2) and Li_(2)S on the MnS surface.The generated Li_(2)S_(2) and Li_(2)S then adsorb the dissolved PSs via chemical reactions among sulfur species during the subsequent PSRR process.This phenomenon mitigates promotor poisoning and continuously improves the reversible capacity.Consequently,the assembled Li-S cell demonstrates excellent electrochemical performance after introducing a conductive interlayer containing a thin piece of carbon nanotube film and MnS promotors.

Remote plasma enhanced cyclic etching of a cyclosiloxane polymer thin film

The continuous evolution of chip manufacturing demands the development of materials with ultra-low dielectric constants.With advantageous dielectric and mechanical properties,initiated chemical vapor deposited(iCVD)poly(1,3,5-trimethyl-1,3,5-trivinyl cyclotrisiloxane)(pV3D3)emerges as a promising candidate.However,previous works have not explored etching for this cyclosiloxane polymer thin film,which is indispensable for potential applications to the back-end-of-line fabrication.Here,we developed an etching process utilizing O2/Ar remote plasma for cyclic removal of iCVD pV3D3 thin film at sub-nanometer scale.We employed in-situ quartz crystal microbalance to investigate the process parameters including the plasma power,plasma duration and O2 flow rate.X-ray photoelectron spectroscopy and cross-sectional microscopy reveal the formation of an oxidized skin layer during the etching process.This skin layer further substantiates an etching mechanism driven by surface oxidation and sputtering.Additionally,this oxidized skin layer leads to improved elastic modulus and hardness and acts as a barrier layer for protecting the bottom cyclosiloxane polymer from further oxidation.

重金属污染土壤化学钝化修复材料研究进展

土壤重金属污染严重威胁着人类的健康和生存环境。一直以来,由于土壤重金属污染的潜伏性、滞后性和复杂性,使之成为环境治理的重大挑战。在诸多土壤重金属污染修复治理技术中,化学钝化修复技术无疑是具有极大研究价值和实际应用价值的修复治理技术手段之一。本文综述了近些年来各类无机、有机、无机-有机复合以及新型化学钝化修复材料的研究进展,为进一步发展重金属土壤污染治理领域化学钝化修复材料的研究提供参考。

High-brightness green InP-based QLEDs enabled by in-situ passivating core surface with zinc myristate

The performance of red InP and blue ZnTeSe-based quantum dots(QDs)and corresponding QD light emitting diodes(QLEDs)has already been improved significantly,whose external quantum efficiencies(EQEs)and luminances have exceeded 20%and 80000 cd m-2,respectively.However,the inferior performance of the green InP-based device hinders the commercialization of full-color Cd-free QLED technology.The ease of oxidation of the highly reactive InP cores leads to high non-radiative recombination and poor photoluminescence quantum yield(PL QY)of the InP-based core/shell QDs,limiting the performance of the relevant QLEDs.Here,we proposed a fluoride-free synthesis strategy to in-situ passivate the InP cores,in which zinc myristate reacted with phosphine dangling bonds to form Zn–P protective layer and protect InP cores from the water and oxygen in the environment.The resultant InP/ZnSe/ZnS core/shell QDs demonstrated a high PL QY of 91%.The corresponding green-emitting electroluminescence devices exhibited a maximum EQE of 12.74%,along with a luminance of over 175000 cd m^(-2)and a long T50@100 cd m^(-2)lifetime of over 20000 h.

钙钛矿太阳能电池化学钝化的研究进展

钙钛矿太阳能电池(PSCs)的钙钛矿薄膜为多晶态,其中不可避免地存在大量缺陷态,这些缺陷态会引起载流子非辐射复合、离子迁移等问题,导致PSCs的效率降低,寿命缩短。通过化学的方法将缺陷钝化,可以有效解决这些问题。概述了钙钛矿薄膜中的缺陷态分类,综述了近期PSCs化学钝化的发展,并对PSCs化学钝化进行了展望。

管式PECVD制备原位掺杂多晶硅的性能研究

报道了管式等离子体增强化学气相沉积(PECVD)的各项沉积参数对硅太阳电池重掺杂多晶硅钝化接触(SiO_(x)/Poly-Si(n^(+)))的影响。TOPCon太阳电池的掺杂多晶硅是通过对沉积的非晶硅高温晶化来实现的,通过改变PECVD的沉积温度、Ar和PH_(3)的流量、沉积功率等沉积参数,可获得不同厚度、结晶度和掺杂浓度的掺杂非晶硅(a-Si(n^(+)))薄膜,然后通过高温退火得到不同的Poly-Si(n^(+))薄膜,从而导致SiO_(x)/Poly-Si(n^(+))钝化接触在钝化质量和载流子选择性等方面的不同特性。最后在沉积温度480℃、Ar流量8 L/min、PH_(3)流量0.8 L/min、沉积功率12000 W、退火温度920℃的条件下获得最佳双面SiO_(x)/Poly-Si(n^(+))/SiN_(x)钝化接触,少子寿命达到6445μs,隐含开路电压(iV_(oc))达到742.7 mV以上,单面饱和电流密度J_(0)低至4.2 fA/cm^(2)。

硫化亚铁钝化清洗剂在芳烃重整装置中的应用

在原油的加工、炼制和储存过程中,都会产生容易自燃的硫化亚铁。在设备检修过程中,当设备处于开放状态时,附着于设备表面的硫化亚铁及油垢就会与空气中的氧气接触,发生强烈的化学反应造成自燃。针对硫化亚铁的自燃问题,研发了一种复合型硫化亚铁钝化清洗剂,并在芳烃重整装置预加氢汽提塔及回流罐中实现了工业应用。装置钝化清洗情况及废液排放情况表明,所研发的硫化亚铁钝化清洗剂不仅对硫化亚铁垢层具有较好的清洗作用,而且能够满足安全环保要求。通过对钝化清洗剂的生产及清洗过程进行总结,明确了下一步的研发方向,并提出了合理化建议。