SURFACE & COATINGS TECHNOLOGY
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2025
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IF 6.1
Pengxing Yu,Ruoyun Wang,Kai Wang,Huabing Liu,Biyou Peng,Hongjian Huang,Junwu Xiang,Haiyang Zhou,Tong Zhou
To enhance the long-term corrosion resistance of 3D-printed AlSi10Mg alloy, this work designed a two-step micro-arc oxidation (MAO) strategy. Given the difficulty of triggering micro-arc discharge in high-Si Al alloys, an intermediate transition layer was first prepared through one-step MAO in a silicate electrolyte. Subsequently, a two-step MAO treatment was performed in a phosphate electrolyte with the addition of K 2 ZrF 6 to seal the ablation holes formed during the one-step MAO process, achieving a self-sealing effect of the MAO coating. Ultimately, a dense ZrO 2 /Al 2 O 3 ceramic coating with Si-W-Zr-P gradient distribution was obtained on the AlSi10Mg surface after the two-step MAO. Electrochemical tests reveal that the two-step MAO coating exhibits exceptional corrosion resistance, with a remarkably low corrosion current density (I corr ) of 3.42 × 10 −9 A·cm −2 , along with a protective efficiency (η p ) of up to 99.8 %. Moreover, no obvious macroscopic corrosion signs are observed on the ZrO 2 /Al 2 O 3 coating after prolonged immersion, and its I corr remains stable at 9.26 × 10 −9 A·cm −2 , indicating durable protective performance. This study offers a novel and controllable strategy for the design of anti-corrosive coatings on 3D-printed high-Si Al alloys.
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
·
IF 6.3
Zhangqiao Zhou,Qi Li,Xian Wang
As third-generation semiconductors advance toward higher frequencies, soft magnetic composites (SMCs) for extreme conditions require concurrent low-loss properties and environmental stability. The Fe-Cr-Si-B-C alloy offers inherent corrosion resistance over other soft magnetic alloys but requires modification for salt spray environment. Insulating coatings are critical for SMCs to meet high-frequency demands. Here, Fe-Cr-Si-B-C powder, engineered via powder atomic layer deposition (PALD), are coated with a nanoscale amorphous Al 2 O 3 layer that provides electrical insulation, physical separation, and enhanced environmental stability while maintaining minimal loss. The PALD-modified SMCs achieve a core loss of 433.3 mW/cm 3 (20 mT, 1 MHz) and 99.7 % corrosion inhibition efficiency. This work proposes a design strategy for high-frequency SMCs combining low loss and extreme environmental durability.
研究领域:
材料科学
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纳米技术
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电磁材料
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腐蚀工程
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半导体技术
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产品关联
DOI
高影响因子
SOLID STATE IONICS
·
2019
·
IF 2.886
Fan Deng,Yongmin Wu,Weiping Tang,Shufeng Song,Zhaoyin Wen,Masashi Kotobuki,Li Lu,Jianyao Yao,Ning Hu,Janina Molenda
The use of garnet-type conductors as electrolytes for safe lithium solid-state batteries is impeded by the lack of critical processing strategy to stabilize and densify the cubic lithium garnets. The synthesis and processing of dense cubic lithium garnets are typically depending on solid state reaction as a result of unintentional Al contamination from the alumina crucibles at temperatures up to 1230 °C. High Al concentration is also believed to induce the sluggish migration of lithium ions . Here, we demonstrate an ultrathin, conformal γ-Al 2 O 3 surface coating on garnet solids by a hybrid microemulsion solid-state method for accomplishing rational and controllable synthesis and processing of dense cubic garnets with low Al concentration. The γ-Al 2 O 3 coating demonstrates fast-ion conducting Al-doped Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 phase with low Al concentration (~0.17 mol per formula unit), low tetragonal-to-cubic phase transformation temperature of 500 °C, and total conductivity of ~4.4 × 10 − 4 S cm − 1 . Specifically, the desired microstructures of the sintered pellets with uniform grains are revealed. As a proof-of-concept, we demonstrate that the nanoscale γ-Al 2 O 3 modification garnet conductor Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 is available to suppress lithium dendrites in symmetric Li/γ-Al 2 O 3 coating Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 /Li cells during lithium plating/stripping at room temperature, with current densities of 0.026 to 0.5 mA cm − 2 . The Li/γ-Al 2 O 3 coating Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 /LiNi 0.5 Co 0.2 Mn 0.3 O 2 cell delivered a high initial discharge capacity of ~164.2 mAh g − 1 , more importantly, an outstanding cycling performance with a capacity retention of 90.16% after 30 cycles at 0.1C and room temperature. This new synthesis route and the utilization of nanoscale γ-Al 2 O 3 surface modification could open up new avenue to lithium garnet conductors with reliable synthesis for all-solid-state lithium batteries application.
研究领域:
材料科学
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电化学
·
固态离子学
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能源存储
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纳米材料
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电池技术
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DOI
高影响因子
ENERGY & FUELS
·
2024
·
IF 5.2
Zhiyuan Kong,Sibao Liu,Hongwang Liu,Guozhu Liu
Endothermic hydrocarbon fuel is the most utilized coolant in regenerative cooling technology for the high-speed aircraft, but it is challenged by the limited heat sink and severe coke deposition. In this study, we propose liquid ammonia as a promising carbon-free fuel with high heat sink for advanced vehicles or aircrafts. The chemical heat sink originates from the endothermic decomposition reaction of ammonia. A series of Ru/CeO2–Al2O3 catalytic coatings were fabricated on stainless-steel tubes using the washcoating method to catalyze the ammonia decomposition reaction and enhance chemical heat sink. The catalytic performance of these Ru/CeO2–Al2O3 coatings for ammonia decomposition was evaluated using an electrically heated tubular reactor. With the Ru/CeO2–Al2O3 coatings of 19 μm, ammonia conversion reaches up to 65%, and a remarkable high heat sink of 5.9 MJ/kg was achieved at 800 °C and 5 MPa. This value is ca. 68% higher than that of the typical hydrocarbon fuel JP-7. This work shows that liquid ammonia can serve as a novel generation high heat sink fuel for advanced engines and aircrafts.
研究领域:
航空航天工程
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材料科学
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化学工程
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产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2019
·
IF 6.864
Shiyong Chu,Xiaojuan Jia,Jie Wang,Kaiming Liao,Wei Zhou,Yong Wang,Zongping Shao
Considering the abundance and low price of sodium , sodium-ion batteries (SIBs) are of particular attractiveness for large-scale electrochemical energy storage . Layered P2–Na 2/3 Mn 1/2 Fe 1/4 Co 1/4 O 2 (NMFC) is a promising cathode material for SIBs because of its large theoretical capacity, however, its high air sensitivity and poor cycling stability seriously limits the practical use. Here, we report nanometre-thick Al 2 O 3 coating of NMFC electrode through atomic layer deposition (ALD) technique can effectively alleviate such deficiencies to obtain an air-insensitive electrode, which was realized by effectively preventing the direct exposure of NMFC to H 2 O and CO 2 present in the air atmosphere. Interestingly, the ultrathin Al 2 O 3 coating did not cause a block for sodium ion intercalation, and a high capacity of 217.9 mA h g −1 at a high cut-off potential of 4.5 V was achieved. More attractively, a capacity retention rate as high as 84.8% was obtained after cycling at a current density of 0.5C over 100 cycles, demonstrating improved electrochemical stability. Based on CV and EIS characterizations, such good cycling stability is associated with the use of the Al 2 O 3 coating layer as well, which effectively avoided the side reactions at the interface of the liquid electrolyte and the active material under high potential.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 36
·16781-16787
·
IF 6.97
Na Li,Zheng Yi,Ning Lin,Yitai Qian
The application of Si-based anode materials is hindered by their extreme volume change, poor cycling stability, and low coulombic efficiency. Solving these problems generally requires a combination of strategies, such as nanostructure designing or surface coating. However, these strategies increase the difficulty of the fabrication process. Herein, a simple and one-pot replacement reaction route was designed to produce an Al2O3 layer anchored on mesoporous Si nanospheres (Si@Al2O3) by employing Al nanospheres with a naturally formed Al2O3 layer as a reducing agent and self-sacrificial template. The obtained Si@Al2O3 was mesoporous, with enough porous space to buffer the volume change and provide a fast lithium ion transfer channel. Furthermore, the coated Al2O3 layer could stabilize the structure and SEI layer of the mesoporous Si nanospheres, endowing the Si@Al2O3 nanospheres with improved initial coulombic efficiency, cycling performance and rate capability. As a result, a high capacity of 1750.2 mA h g−1 at 0.5 A g−1 after 120 cycles and 1001.7 mA h g−1 at 2 A g−1 after 500 cycles were delivered for lithium ion batteries. The good performance could be attributed to the mesoporous structure and the outer-coated Al2O3 layer.
研究领域:
材料科学
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电化学
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纳米技术
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能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Tong Wei,Kai Lian,Jiaqi Tao,Hu Zhang,Da Xu,Jiachen Han,Chao Fan,Zihui Zhang,Wengang Bi,Chun Sun
Luminescent solar concentrators (LSCs) can be used as large-area sunlight collectors, which show great potential in the application of building-integrated photovoltaic areas. Achieving highly efficient LSCs requires the suppression of reabsorption losses while maintaining a high photoluminescence quantum yield (PLQY) and broad absorption. Perovskites as the superstar fluorophores have recently emerged as candidates for large-area LSCs. However, highly emissive perovskites with a large Stokes shift and broad absorption have not been obtained up to now. Here, we devised a facile synthetic route to obtain Mn-doped multiple quantum well (MQW) Br-based perovskites. The Br-based perovskite host ensures broad absorption. Efficient energy transfer from the exciton to the Mn dopant produces a large Stokes shift and high PLQY simultaneously. By further coating the perovskites with Al2O3, the stability and PLQY are greatly elevated. A large area of liquid LSC (40 cm × 40 cm × 0.5 cm) is fabricated, which possesses an internal quantum efficiency (ηint) of 47% and an optical conversion efficiency (ηopt) reaching 11 ± 1%, which shows the highest value for large-area LSCs.
研究领域:
材料科学
·
可再生能源
·
太阳能
·
光子学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）