POLYMER ENGINEERING AND SCIENCE
·
2024
·Vol. 64
·期 7
·2988-3002
·
IF 3.2
Sun Yun,Xuefeng Pan,Feng Zhang,Xuelian He
The cavitation process of high-performance HDPE/UHMWPE blends with a uniform dispersion of UHMWPE during cold stretching was investigated. It was observed that incorporating a small amount of UHMWPE into the HDPE matrix resin can serve as a nucleating agent, increasing the number of contact sites and accelerating the crystallization rate. This leads to the formation of thicker lamellar crystals and tethered molecules, ultimately enhancing the mechanical properties of the HDPE matrix. Furthermore, the relationship between the natural tensile ratio and strain-hardening modulus was confirmed. Microstructural changes within the blends were also explored. As the drawing tangles in the middle, the cavities subsequently evolve by collapsing and merging to align parallel to the tensile direction, culminating in tensile damage forming a large crack in the final macroscopic form. As a result, the presence of more tethered molecules in the later stages of stretching inhibits further cavity growth. Highlights The HDPE/UHMWPE blends were prepared by solution blending and ultrasound-assisted twin-screw extrusion. The mechanisms underlying the formation and evolution of cavities in HDPE/UHMWPE blends, which lead to stress whitening during tensile damage, were examined by using DSC and SAXS/WAXD. The relationship between microstructure and mechanical properties was analyzed by cold-drawing the molded blended sheets at room temperature.
研究领域:
材料科学
·
高分子物理
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 22
·5405
·
IF 3.1
Wenjie Li,Zhe Li,Fang-Yuan Zeng,Qi Zhang,Liwei Guo,Dan Li,Yong-Hui Ma,Zhi-Quan Liu
With the advancement of high-integration and high-density interconnection in chip manufacturing and packaging, Cu bumping technology in wafer- and panel- level packaging is developed to micrometer-sized structures and pitches to accommodate increased I/O numbers on high-end integrated circuits. Driven by this industrial demand, significant efforts have been dedicated to Cu electroplating techniques for improved pillar shape control and solder joint reliability, which substantially depend on additive formulations and electroplating parameters that regulate the growth morphology, crystal structure, and impurity incorporation in the process of electrodeposition. It is necessary to investigate the effect of an additive on Cu pillar electrodeposition, and to explore the Kirkendall voids formed during the reflowing process, which may result from the additive-induced impurity in the electrodeposited Cu pillars. In this work, a self-synthesized polyquaterntum (PQ) was made out with dual suppressor and leveler effects, and was combined with prototypical accelerator bis- (sodium sulfopropyl)-disulfide (SPS) for patterned Cu pillar electroplating. Then, Sn96.5/Ag3.0/Cu0.5 (SAC305) solder paste were screen printed on electroplated Cu pillars and undergo reflow soldering. Kirkendall voids formed at the joint interfaces were observed and quantified by SEM. Finally, XRD, and EBSD were employed to characterize the microstructure under varying conditions. The results indicate that PQ exhibits significant suppressive and levelled properties with the new structure of both leveler and suppressor. However, its effectiveness is dependent on liquid convection. PQ and SPS work synergistically, influencing the polarization effect in various convective environments. Consequently, uneven adsorption occurs on the surface of the Cu pillars, which results in more Kirkendall voids at the corners than at the center along the Cu pillar surface.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Sustainable Energy & Fuels
·
2023
·Vol. 8
·期 3
·604-609
·
IF 5.6
Jinhui Zhang,Chuanhe Ma,Haixuan Gao,Jinchun Jiang,Hailong Wang
An over-thick MoSe2 layer and numerous voids at the absorbing layer inside and backside lead to a relatively low Jsc and PCE of CZTSSe solar cells. In previous studies, MoO2 and MoO3 sacrificial layers have been commonly used to eliminate those voids and reduce the thickness of MoSe2 layers. However, there is still no clarity about which one is more effective. In this work, we prepared MoO2 and MoO3 sacrificial layers on the surface of Mo-coated SLG substrates by air annealing and ammonia (NH3·H2O) etching, respectively. J–V testing shows that both MoO2 and MoO3 can effectively improve the Jsc and PCE of CZTSSe solar cells, wherein MoO3 is more effective. Comparative analysis shows that the electrical mechanism of Jsc and PCE improvement lies in the significant reduction of device series resistance (Rs). SEM images and XRD pattern results indicate that the reason for Rs decreasing is void elimination and MoSe2 layer thickness reduction from 600 nm to 270 nm after applying MoO3. With the aid of the MoO3 sacrificial layer, the PCE of the CZTSSe device increases from 7.51% to 9.58% (total area 0.21 cm2) without the MgF2 anti-reflection layer.
研究领域:
材料科学
·
太阳能
·
光伏技术
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产品关联
DOI
高影响因子
RARE METALS
·
2025
·
IF 11
Zhang Qi,Zhang Zhiqiang,Zeng Fangyuan,Li Wenjie,Liu Jinhao,Ai Shubo,Zheng Yun,Li Zhe,Shao Huaiyu,Liu Zhi-Quan
Kirkendall voids (KVs) at the Cu/Sn interface are a typical failure in integrated circuits, leading to solder joint cracking and electrical disconnection. Although the formation of KVs has been attributed to the difference in atomic diffusion rates at the Cu/Sn interface, the role of Cu intrinsic "quality" parameters (crystal defects) in this process remains unclear. This work systematically investigated the effects of Cu crystal defects on KVs: Cu substrates with different lattice defects and grain boundaries were prepared using proprietary electrodeposition additives, and the number of defects was quantitatively characterized by micro-strain, geometric dislocation density, and geometric phase analysis. The thermal aging experiments further showed that the formation of intermetallic compounds and KVs was related to crystal defect energy. When the grain boundary energy was higher than the lattice energy, the additional driving force resulted in short-circuit diffusion, causing local Cu depletion and voids. The low-crystal-defect samples maintained the local Cu/Sn interdiffusion equilibrium, resulting in fewer voids after 1000 h. This study emphasizes that regulating the crystal defects can reduce KVs and provides a new insight for improving the integrated solder joint’s reliability.
研究领域:
材料科学
·
微电子学
·
固体物理
·
应用物理学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2018
·
IF 4.484
Jialun Tang,Sheng Huang,Zhaohan Li,Huaibin Shen,Zhao Lv,Haizheng Zhong
In this work, we reported the morphology evolution (formation of voids & size reduction) of gradient-alloyed CdxZn1–xSeyS1–y@ZnS quantum dots under electron irradiation during transmission electron microscopy observation. By investigating the correlations between shell gradients and morphology evolution, the formation of voids can be explained by the continuous electron irradiation-induced atomic movement under interfacial strain. On the other hand, the size reduction can be attributed to the elastic scattering-enabled sputtering of surface atoms. The as-formed voids of CdxZn1–xSeyS1–y@ZnS quantum dots with CdS-rich cores are much larger than those of ZnSe-rich ones, and the sizes of voids decreased with the increasing of shell thickness. The comparison of the morphology evolution of CdxZn1–xSeyS1–y@ZnS core–shell quantum dots with different composition gradients demonstrated that the size and shape of as-formed voids illustrate the strain characteristics of shell gradient. This provides a guideline to understand the strain effects in gradient-alloyed core–shell quantum dots through transmission electron microscopy measurement. We believe the deep insights into gradient-alloyed CdxZn1–xSeyS1–y@ZnS core–shell quantum dots would push forward their optimization toward commercialized light-emitting technology.
研究领域:
材料科学
·
纳米技术
·
物理学
✓ 已验证
DOI
高影响因子
Science Advances
·
2025
·Vol. 11
·期 14
·
IF 12.5
Haowen Gao,Chen Lin,Yuanpeng Liu,Jiashun Shi,Bowen Zhang,Zhefei Sun,Zhao Li,Yu Wang,Menghao Yang,Yong Cheng,Ming-Sheng Wang
The formation of interface voids, peculiar to the solid-solid contact between metal anodes and solid electrolytes (SEs), has become a fundamental obstacle for developing practical lithium metal solid-state batteries (SSBs). Addressing this issue requires the operando observation of void evolution with high spatio-temporal resolution and the direct linkage of voids to solid-state electrochemistry. Here, we present such an attempt by visualizing both the stripping and plating interfaces of a micron-sized SSB cycled in galvanostatic mode in a transmission electron microscope. Various voltage responses in the charge/discharge curves are well correlated to the nucleation, growth, and refilling of single voids. Notably, two distinct modes of Li stripping, namely, void-growth stripping and void-free stripping, are experimentally identified. We unveil the roles of stack pressure and current density on void evolutions, which suggests a mechanism of void suppression without involving plastic deformation of Li metal. Furthermore, Li|SE|Li symmetric SSBs enabling repeated void-free cycling without stack pressure are in situ demonstrated.
研究领域:
材料科学
·
电化学
·
纳米技术
·
储能
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2023
·
IF 17.1
Shuxian Zhang,Jianchao Chen,Chunyan Zhu,Qingyuan Liu,Qingyu Li,Renbo Liu,Xiaobo Jiang,Yijie Yan,Shengjian Sun,Longwei Yin,Rutao Wang
All-solid-state batteries (ASSBs) with a Li metal anode are expected to be one of the most promising energy storage systems to achieve high energy density. However, the interfacial instability between the Li metal anode and solid-state electrolyte (SSE) limits the rate capability and cycling stability of ASSBs. The main issue is the formation of voids at the Li/SSE interface during Li stripping due to the slow diffusion of Li within the bulk Li metal, then increasing internal cell resistance and inducing the formation of lithium dendrites. To address these issues, a composite Li anode (LAO) composed by Li–Ag alloy and Li2O is constructed by mixing the stoichiometric metal Li and Ag2O directly. LAO anode is capable of improving bulk Li diffusion kinetics and inhibiting the formation of interfacial voids effectively, achieving a high critical current density over 1.5 mA cm–2 and long stable cycling over 1000 h at 1 mA cm–2. The ASSBs, employing LAO as the anode, Li6PS5Cl as the SSE, and LiCoO2 as the cathode, exhibit superior rate capability and stable cycling over 4000 cycles at 5 C. Moreover, ASSBs can operate stably with a high LiCoO2 loading of 17.8 mg cm–2 for more than 100 cycles at 0.2 C.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2021
·Vol. 31
·期 41
·2104863
·
IF 18.808
Yang Liu,Haowen Liu,Yitao Lin,Yuxing Zhao,Hua Yuan,Yipeng Su,Jifang Zhang,Shuaiyang Ren,Haiyan Fan,Yuegang Zhang
Although employing solid polymer electrolyte (SPE) in all-solid-state lithium/sulfur (ASSLS) batteries is a promising approach to obtain a power source with both high energy density and safety, the actual performance of SPE-ASSLS batteries still lag behind conventional lithium/sulfur batteries with liquid ether electrolyte. In this work, combining characterization methods of X-ray photoelectron spectroscopy, in situ optical microscopy, and three-electrode measurement, a direct comparison between these two battery systems is made to reveal the mechanism behind their performance differences. In addition to polysulfides, it is found that the initial elemental sulfur can also dissolve into and diffuse through the SPE to reach the anode. Different from the shuttle effect that causes uniform corrosion on the anode in a liquid electrolyte, dissolved sulfur species in SPE unevenly passivate the anode surface and lead to the inhomogeneous Li + plating/stripping at the anode/SPE solid-solid interface. Such inhomogeneity eventually causes void formation at the interface, which leads to the failure of SPE-ASSLS batteries. Based on this understanding, a protection interlayer is designed to inhibit the shuttling of sulfur species, and the modified SPE-ASSLS batteries show much-improved performance in cycle life.
研究领域:
材料科学
·
电化学
·
储能
·
电池技术
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2024
·
IF 5.5
Yue Zhang,Junye Chen,Yuanrong Cheng,Shuo Han,Fei Xiao
The void-free deposition of small-sized and high-aspect ratio interconnect structures requires stronger suppressors than conventional polyethers. In this work, thioether was introduced into polyether to develop novel suppressors with improved adsorption on electrode. The structure of thioether-modified polyether can be easily tailored by choosing proper polyether and thiol compound, thus providing a simple way to regulate electrochemical properties of the suppressor. The electrochemical and copper filling performance related to the molecular structure of novel suppressors were systematically investigated. Thioether-modified polyether, which retains the strong polarizability of typical suppressor and exhibits high resistance to accelerator desorption, can significantly suppress copper deposition on feature sidewalls. This enabled defect-free filling of narrower features at a concentration much lower than the typical usage concentration of suppressor. The modified polyethers with ethylene-propylene-ethylene (EPE) oxide triblock ether chains exhibited higher polarization strength and concentration dependence, facilitating the higher deposition current at the bottom during filling. The length and block ratio of ether chain further influenced the anti-desorption ability of the modified polyether, thereby impacting their suppression on sidewalls, which is crucial in filling process. The convenient structural adjustments for thioether-modified polyether, combined with the derived structure-property relationship, contribute to the development of new suppressors with strong adsorption performance.
研究领域:
材料科学
·
电化学
·
半导体制造
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Muneeb Ahmed,Lisheng Zhong,Fei Li,Rui Sui,Ming Wu,Jinghui Gao
This research investigates the transition from a micropinned to a polymeric alloy structure in crosslinked-polyethylene-polystyrene (XLPE-PS). Incorporating 2 wt% 10 μm PS particles into low-density polyethylene (LDPE) and crosslinking with 2 wt% dicumyl peroxide (DCP) forms XLPE-PS structures. The polymeric alloy structure, formed at 220°C extrusion, contrasts with the micropinned formed at 150°C. Morphological, thermo-structural, chemical, and crystal properties are examined to understand their impact on electrical properties and charge transport mechanisms. Results indicate that the polymeric alloy effectively resolves void/crack issues, whereas the micropinned exhibits phase separation. Both structures exhibit a benzene-crosslinked network, and variations in these structures lead to significant changes in thermo-structural, chemical, and crystalline properties. The polymeric alloy XLPE-PS shifts the polyethylene (PE) hkl crystal planes, confirming phase shift and optimal alloying. The structural alterations reveal deeper traps and higher densities in the polymeric alloy XLPE-PS, leading to significantly improved electrical properties, including reduced DC conductivity by up to 1.3 and 0.7 decades at 30 and 90°C, and increased DC breakdown strength by up to 40.34% and 16.17% at 30 and 90°C, respectively, compared with micropinned XLPE-PS. This research offers insights into stable high-voltage insulation development.
研究领域:
材料科学
·
电气工程
·
高分子化学
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·Vol. 37
·期 20
·2418720
·
IF 26.8
Jianhui Liu,Lina Wang,Yong Cheng,Minyi Huang,Longze Zhao,Chenxi Zheng,Wangqin Li,Haowen Gao,Zhao Li,Zhenhai Wen,Guangfu Luo,Zhengliang Gong,Yong Yang,Ming-Sheng Wang
Solid-state lithium metal batteries (SSLMBs) are now under intensive research for their high energy density and excellent safety. However, the Li transport limitation in Li metal anode (LMA) leads to mass/stress accumulation, dendrite initiation and void formation at the interface, which seriously hinders the development of SSLMBs. Herein, it is demonstrated through in situ electron microscopies that a mixed ionic-electronic conducting (MIEC) 3D host can promote the Li transport in LMA by increasing the diffusion pathways along the carbonaceous framework, carbon/Li interface and Li metal surface, enabling a fast and long-distance (nearly 100 µm) diffusion of Li atoms in LMA. Consequently, the spatio-temporal sequence of Li plating/stripping can be fundamentally changed. Specifically, both deposition and dissolution can occur far away from the interface, thereby mitigating the dendrite and void issues. Impressively, the resulting cells with carbonaceous hosts can achieve excellent cyclability and the highest capacity (28.8 mAh cm −2 ) so far. This work provides valuable insight for understanding Li transport and deposition/dissolution mechanisms in MIEC host-based LMAs, and a feasible solution for tackling the interface issues without involving stack pressure in SSLMBs.
研究领域:
材料科学
·
储能技术
·
电化学
·
纳米科技
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-11
·
IF 14.7
Gao Ziyao,Zhao Chenglong,Zhou Kai,Wu Junru,Tian Yao,Deng Xianming,Zhang Lihan,Lin Kui,Kang Feiyu,Peng Lele,Wagemaker Marnix,Li Baohua
Nickel-rich layered oxide cathodes promise ultrahigh energy density but is plagued by the mechanical failure of the secondary particle upon (de)lithiation. Existing approaches for alleviating the structural degradation could retard pulverization, yet fail to tune the stress distribution and root out the formation of cracks. Herein, we report a unique strategy to uniformize the stress distribution in secondary particle via Kirkendall effect to stabilize the core region during electrochemical cycling. Exotic metal/metalloid oxides (such as Al 2 O 3 or SiO 2 ) is introduced as the heterogeneous nucleation seeds for the preferential growth of the precursor. The calcination treatment afterwards generates a dopant-rich interior structure with central Kirkendall void, due to the different diffusivity between the exotic element and nickel atom. The resulting cathode material exhibits superior structural and electrochemical reversibility, thus contributing to a high specific energy density (based on cathode) of 660 Wh kg −1 after 500 cycles with a retention rate of 86%. This study suggests that uniformizing stress distribution represents a promising pathway to tackle the structural instability facing nickel-rich layered oxide cathodes.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）