会泽铅锌矿伴生稀散金属锗的选矿富集行为分析

会泽铅锌矿为特高品位富锗银铅锌多金属矿,伴生稀散金属锗的赋存状态可能以类质同象的形式进入矿物的晶格、吸附形式存在于有机质中和以独立矿物的形式存在,锗主要赋存在锌矿物中,闪锌矿、硅锌矿、菱锌矿中的锗合计占总锗的95.72％.在选矿生产中,锗主要富集在锌精矿中,锌精矿中锌的回收率为94.65％,但锗回收率为78.89％,锌...     

柔性单晶锗PIN二极管在关态下的建模研究

介绍了柔性单晶锗纳米薄膜（GeNM ）PIN 二极管的制备方法和反向偏置下对应不同弯曲状态下的射频特性。为了定量研究在反向偏置下机械弯曲对柔性PIN二极管射频特性的影响，分别搭建了不同弯曲半径下的等效电路模型。通过研究不同机械应力作用下模型中的各个参数的变化得到二极管内部电阻，寄生电感，p＋ p-结的电阻以及p-n＋结的电容为影响其射频特性的主要因素，机械弯曲使这些参数值单调变化，导致柔性单晶锗PIN二极管关态下的射频特性变好。这在应变测量领域显示出很大的发展应用潜力。     

离子注入对单晶锗力学性能影响的分子动力学研究

为改善单晶锗的硬脆力学特征，用分子动力学模拟方法研究了3种不同剂量的离子注入对单晶锗表面的改性机理。分析结果表明，离子注入对锗基体造成了非晶相损伤，纳米压痕过程表现为晶格演化。纳米压痕结果揭示了非晶相的存在能够降低单晶锗的硬度和脆性，提高塑性。此外，锗基体的非晶相损伤程度和硬度与离子剂量有关。随着剂量的增加，非晶损伤程度加深，硬度降低。     

单晶锗纳米尺度二次划痕特性北大核心

现有的单一划痕法磨削机理研究不能反映多个磨粒随机分布所引起的多次划痕之间的相互作用,为了阐明单晶锗磨削过程中多次划痕相互作用对材料去除机理的影响,采用Cube压头对单晶锗进行了不同刻划力的多次刻痕实验。结合Cube压头的几何形状与刻划表面的弹性回复,建立了划痕硬度模型,并对二次刻划中的划痕深度、应力场、弹性回复率、划痕硬度和摩擦特性进行分析,研究第一次刻划时载荷变化对于后续刻划的影响。结果表明:随着第一次刻划载荷的增大,二次刻划时单晶锗的脆塑转变的临界载荷、临界深度、弹性回复率和划痕硬度均在减少,幂函数对于切向力、法向力与刻划深度的拟合准确度降低;最大主应力增加,导致裂纹不断扩展,最终造成材料发生脆性断裂。     

Progress and Perspectives of Lithium Aluminum Germanium Phosphate-Based Solid Electrolytes for Lithium Batteries

Solid-state lithium batteries are considered promising energy storage devices due to their superior safety and higher energy density than conventional liquid electrolyte-based batteries. Lithium aluminum germanium phosphate (LAGP), with excellent stability in air and good ionic conductivity, has gained tremendous attention over the past decades. However, the poor interface compatibility with Li anode, slow Li-ion conduction in thick pellets, and high-temperature sintering procedure limit the further development of LAGP solid electrolytes in practical applications. This review comprehensively summarizes the crystal structure, Li-ion conducting mechanism, and various synthesis methods, especially the latest thin-film preparation approach. The underlying reason for Li/LAGP interfacial instability is identified, followed by several advanced interface engineering strategies, for example, introducing a functional interlayer. The integration design of LAGP-based solid electrolytes and cathode is also highlighted to enable high-loading cathodes. Additionally, recent progress of lithium-oxygen and lithium-sulfur batteries with LAGP-based solid electrolytes is discussed. Moreover, the different Li-ion migration pathways, preparation procedures, and electrochemical performance of polymer-LAGP composite solid electrolytes in Li-ion batteries are introduced. Lastly, the remaining challenges and opportunities are proposed to encourage more efforts in this field. This review aims to provide fundamental insights and promising directions toward practical LAGP-based solid-state batteries.     

Self-Assembly of Mixed-Dimensional GeS1−xSex (1D Nanowire)–(2D Plate) Van der Waals Heterostructures

The integration of dissimilar materials into heterostructures is a mainstay of modern materials science and technology. An alternative strategy of joining components with different electronic structure involves mixed-dimensional heterostructures, that is, architectures consisting of elements with different dimensionality, for example, 1D nanowires and 2D plates. Combining the two approaches can result in hybrid architectures in which both the dimensionality and composition vary between the components, potentially offering even larger contrast between their electronic structures. To date, realizing such heteromaterials mixed-dimensional heterostructures has required sequential multi-step growth processes. Here, it is shown that differences in precursor incorporation rates between vapor–liquid–solid growth of 1D nanowires and direct vapor–solid growth of 2D plates attached to the wires can be harnessed to synthesize heteromaterials mixed-dimensional heterostructures in a single-step growth process. Exposure to mixed GeS and GeSe vapors produces GeS_1−xSe_x van der Waals nanowires whose S:Se ratio is considerably larger than that of attached layered plates. Cathodoluminescence spectroscopy on single heterostructures confirms that the bandgap contrast between the components is determined by both composition and carrier confinement. These results demonstrate an avenue toward complex heteroarchitectures using single-step synthesis processes.     

Ultrasonication-Assisted Seed Screening Enables Oriented and Efficient Low-Dimensional Crystal-Structural Thin-Film Photovoltaics

Ultrasonication-assisted liquid exfoliation of layered materials is widely used to produce a large number of 2D nanosheets due to its simplicity, universality, and mass production. Here, the utility of ultrasonication is extended from liquid exfoliation to seed screening in the case of layered GeSe and GeS. It is found that the ultrasonic stripping force can also be used to selectively remove the lying seeds interacting with substrate through weak van der Waals (vdW) forces while retaining the standing seeds connected with substrate via tightly covalent bonds. The standing seeds then induce the growth of 2D crystal-structural films with standing orientation. This thereby enables efficient carrier transport within covalently bonded layers, instead of poor transport between layers held together by vdW forces. The resulting standing-oriented GeSe films exhibit a 21-times increase in carrier mobility compared to lying-oriented films. As a result, this study demonstrates the highest power conversion efficiencies of 6.1% and 10.5% under AM1.5G 1- and 0.01-sun illumination reported for GeSe solar cells, respectively.     

提高锗精矿质量

低锗单宁锗采用"盐酸+盐浸出脱杂—三段水逆流洗涤—煅烧"工艺可以明显提高锗精矿的品质。在液固比(4.0～4.5)∶1、浸出脱杂温度40～60℃、浸出脱杂时间120～180min时,杂质Ca、Pb、Zn和Fe脱除率分别约为90%、95%、92%和80%,脱杂单宁锗中含Ge约4%,产率约45%。煅烧产率约15%,Ge收率>95%,煅烧锗精矿含Ge约27%。