Journal of Advanced Ceramics
·
2021
·Vol. 10
·期 5
·1129-1139
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IF 6.707
Wu Pengfei,Shi Benyang,Tu Huibin,Guo Changqing,Liu Anhua,Yan Guan,Yu Zhaoju
Severe volume expansion and inherently poor lithium ion transmission are two major problems of silicon anodes. To address these issues, we proposed a pomegranate-type Si/C composite anode with highly dispersed tiny silicon particles as the core assisted by small amount of SiC. Skillfully exploiting the high heat from magnesiothermic reduction, SiC can assist the good dispersion of silicon and provide good interface compatibility and chemical stability. The silicon anchored to the carbon shell provides multipoint contact mode, that together with the carbon shell frame, significantly promoting the transfer of dual charge. Besides, the pomegranate-type microcluster structure also improves the tap density of the electrode, reduces the direct contact area between active material and electrolyte, and enhances the electrochemical performance.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Zhuqing Zhao,Muya Cai,Yan Zhao,Hongwei Xie,Yan Xin Zhuang,Huayi Yin
The choice of SiO2 precursor plays an important role in designing and synthesizing specific nanostructured Si materials with improved Li-storage performance. Herein, various SiO2 precursors are used to prepare nanostructured Si spheres via zincothermic reduction and their effects on the reduction process are systematically investigated. It is found that the size and structure of SiO2 precursors have a significant effect on the zincothermic reduction process. Among various precursors, nano-SiO2 and bio-SiO2 (e.g., SiO2 derived from rice husk (RH-SiO2) and bamboo leaves (BL-SiO2)) are successfully reduced to Si spheres, while crystalline bulk SiO2 (i.e., micro-SiO2) cannot be reduced. The ease of zincothermic reduction of nano- and bio-SiO2 is due to the high surface area of SiO2 that allows sufficient and facile chlorination–reduction reactions. In addition, the hollow Si spheres prepared from nano-SiO2, RH-SiO2, and BL-SiO2 are used as anode materials for lithium-ion batteries, all of which exhibit good electrochemical performances, delivering the specific discharge capacities of 947.6, 1130.7, and 1050 mAh g–1 over 300 cycles at 1 A g–1, respectively. Overall, this work offers a deeper understanding of zincothermic reduction and demonstrates the broad applicability of zincothermic reduction for the preparation of nanostructured Si from a variety of Si sources.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yifan Zhang,Yangyang Guo,Shanshan He,Honglin Guo,Lei Luo,Mengran Li,Tingyu Zhu,Tao Guo,Yanxi Deng
CO 2 capture from blast furnace gas is of great significance for carbon reduction. 13X zeolites are frequently employed as CO 2 adsorbents. Nevertheless, their large-scale utilisation in industrial applications is impeded by the presence of H 2 O and H 2 S in blast furnace gas. To develop CO 2 adsorbents suitable for carbon capture from blast furnace gas, a series of Faujasite (FAU) zeolites were prepared in this study by modulating Si/Al. The findings revealed that the separation coefficients of CO 2 /N 2 and CO 2 /CO increased by 72 % and 144 %, respectively, and that the H 2 O adsorption decreased by 23 % when Si/Al was increased from 1.45 to 2.93. Furthermore, breakthrough experiments demonstrated that enhancing the Si/Al ratio of FAU zeolite can effectively reduce the dynamic adsorption capacity of H 2 O and H 2 S. Physicochemical characterizations of the zeolite before and after H 2 S adsorption were performed: CO 2 and N 2 adsorption isotherms, thermogravimetry, In-situ FT-IR and XPS. The present study investigates the effect of H 2 S adsorption on zeolites with varying Si/Al ratios. When combined with DFT calculations, the results demonstrate that the elevated Si/Al ratio of the zeolite results in a significant increase in sulfur resistance and easier deposition of H 2 S in the form of sulfate on the zeolite surface. It indicates that the modulation of Si/Al ratio is an effective method to improve the water and sulfur resistance of zeolites, and provides core material support for the practical application of large-scale carbon capture technology for blast furnace gas.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Jia Ding,Yuanhao Wu,Shurong Wu,Shengyu Zhou,Yulong Li,Chao Fan,Hanxiao Liu,Penghui Ren,Shengwei Deng,Jianguo Wang
The direct carbonylation of glycerol with CO 2 is an alternative route to produce high-valued glycerol carbonate, which however faces challenges like low catalytic conversion due to the thermodynamic equilibrium limitation. In this work, ZSM-5 membranes with different Si/Al molar ratios were prepared by hydrothermal method, and coupled with Ce–La–Co mixed metal oxide (CeLaCo-MMO) catalysts for enhancing the glycerol carbonylation performance by in situ water separation. The Si/Al ratio of ZSM-5 showed significant influences on the water permeance, separation selectivity, and catalytic performance for glycerol carbonylation, due to the precise concentration control of Na + gated water transport channels. The reaction-separation coupling process achieved a glycerol conversion of 40.1 %, which was about 4.5 times higher than the conventional batch reactor. The as-synthesized ZSM-5 membrane also exhibited good reusability performance in the cycling test. This work provides a new in-situ water separation strategy for boosting glycerol carbonylation performance without consuming chemical or physical dehydrating agents as compared to the investigations in the literature.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Chuanhui Zhang,He Huang,Genqin Li,Lei Wang,Liang Song,Xuebing Li
Series of 10% MnO x /HZSM-5 catalysts with different zeolitic Si/Al ratios were prepared by an incipient impregnation method and evaluated for the catalytic oxidation of toluene. Characterization results indicated that all catalysts exhibited similar textural and redox properties but variable surface acidity. Catalytic testing results showed that the catalytic activities over these catalysts followed a descending order of 10% MnO x /HZSM-5-25 > 10% MnO x /HZSM-5-50 > 10% MnO x /HZSM-5-75, where 10% MnO x /HZSM-5-25 exhibited the optimum catalytic activity and excellent catalytic durability under dry condition and good water-resistant ability under humid condition. A good linear relationship between the toluene conversion efficiency (TOF Mn ) and the total acidity over MnO x /HZSM-5 catalysts was obtained, which revealed the crucial role and promotional effect of zeolitic acidity acting as a promoter on the catalytic activity for toluene oxidation.
研究领域:
催化化学
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环境科学
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2018
·Vol. 20
·期 40
·6351-6357
·
IF 3.304
Kui-Suo Yang,Yi-Lian Li,Yang-Yang Ma,Li-Na Feng,An-Ping Wu,Yan Qiao,Jin-Rong Bao,Wen-Xian Li,Xiao-Wei Zhu,Ran-Bo Yu
A novel core–shell–shell SiO2@CePO4:Tb@SiO2 submicro-sphere was controllably synthesized by a bridging ligand organosilane HOOCC6H4N(CONH(CH2)3Si(OCH2CH3)3)2 (MABA-Si) connecting the silica core and rare earth ions. The as-synthesized samples were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (IR). It is found that SiO2@CePO4:Tb@SiO2 has a ∼25 nm outermost shell, a ∼4 nm intermediate shell, and a ∼200 nm core. SiO2@CePO4:Tb@SiO2 exhibits stable photoluminescence properties in aqueous solution: its photoluminescence intensity was unquenched even after 15 days. The core–shell–shell submicro-spheres were found to have better photoluminescence than the core–shell submicro-spheres because the SiO2 shell protected the phosphor materials and then improved its photoluminescence intensity and biocompatibility. A formation mechanism of the core–shell–shell SiO2@CePO4:Tb@SiO2 submicro-spheres was proposed. Thus, the low-cost preparation of the core–shell–shell SiO2@CePO4:Tb@SiO2 submicro-spheres could be rationally achieved using SiO2.
研究领域:
材料科学
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纳米技术
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光学
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化学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Zihan Zhou,Yunwen Wu,Silin Han,Tao Hang,Huiqin Ling,Jie Guo,Su Wang,Ming Li
3D NAND is one of the most promising storage devices due to its high storage density and low energy consumption. Selective wet etching of Si 3 N 4 by hot-concentrated phosphoric acid (PA) solution is a key process for 3D NAND fabrication. However, the channel material, polycrystalline silicon (poly-Si), is unexpectedly dissolved due to its inevitable exposure to the PA etching solution, which causes device failure and thus limits the stacking density of 3D NAND. Herein, to avoid the detrimental dissolution of poly-Si, we unveil the mechanism of poly-Si dissolution in PA solution from kinetic and thermodynamic perspectives. We find that the etch process shows a two-stage reaction, in which H 2 O plays a key role in lowering the activation barrier for poly-Si etching. Further thermodynamic analysis demonstrates that poly-Si prefers to be oxidized by H 2 O to suboxide rather than to SiO 2 . Combined with surface chemistry characterization, we propose the dissolution mechanism as a two-stage process involving the dissolution of suboxide interface and bulk poly-Si, where the nucleophilic substitution of Si–H with Si–OH on bulk poly-Si surface determines the overall etch rate. This study advances the 3D NAND development by establishing a theoretical foundation for identifying and implementing efficacious strategies to impede detrimental dissolution.
研究领域:
半导体器件
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材料科学
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纳米技术
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化学工程
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2015
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IF 4.504
Yonghai Song,Li Zuo,Shouhui Chen,Jiafeng Wu,Haoqing Hou,Li Wang
Novel porous cage-like carbon (C)/nano-Si nanocomposites as anode materials for lithium-ion batteries (LIBs) was prepared based on nano-Si@zeolitic imidazolate frameworks (ZIF-8)-templated method. In this strategy, p-aminobenzoic acid was initially grafted onto nano-Si to form benzoic acid-functionalized nano-Si, and then nano-Si@ZIF-8 was constructed by alternately growing Zn(NO 3 ) 2 ·6H 2 O and 2-methylimidazolate on benzoic acid-functionalized nano-Si under ultrasound. The novel porous cage-like nano-Si/C nanocomposites were fabricated by pyrolyzing the resulted nano-Si@ZIF-8 and washing with HCl to remove off ZnO. Scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, Raman spectra and N 2 adsorption/desorption isotherms were employed to characterize the porous cage-like nano-Si/C nanocomposites. The resulted nano-Si/C nanocomposites as anode materials for LIBs showed a high reversible capacity of ∼1168 mA h g −1 at 100 mA g −1 after 100 cycles, which was higher than many previously reported Si/C nanocomposites. The porous nanostructure, high specific surface area and good electrical conductivity of the cage-like nano-Si/C nanocomposites contributed together to the good performance for LIBs. It might open up a new way for application of silicon materials.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
·
IF 9.4
Xiaochen Zhang,Fengjun Deng,Ze Liu,Yingjian Yu
Si-air batteries have a high energy density, high theoretical voltage, and long lifetime, but they present a low anode utilization rate in a potassium hydroxide electrolyte. In this work, a ZIF-8 protective layer was prepared and modulated by a secondary growth method and then applied to protect the Si flat and Si nanowire (NW) anodes of a Si-air battery. By adjusting the conversion ratio, particle size, and crystallinity of ZIF-8 on the Si surface, the contact mode of the Si anode with water and OH – was controlled, thus achieving long-term corrosion and passivation resistance. Si NWs@ZIF-8 exhibited the highest average discharge voltage of 1.16 V, and the Si flat@ZIF-8 anode achieved the longest discharge time of 420 h. This work confirms that ZIF-8 acts as an anode protective layer to improve the properties of Si-air batteries and also provides valuable insights into the protection of Si anodes by MOFs.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2021
·
IF 4.094
Yixin Li,Li Liu,Xiaoyang Liu,Yi Feng,Beichen Xue,Liyun Yu,Lijie Ma,Yanchao Zhu,Yimin Chao,Xiaofeng Wang
The comprehensive utilization of Si-rich biomass is restrained by macromolecular lignin and a large amount of ash. In this study, rice husks (RHs) are treated as a representative by alkali extraction and acid precipitation, and the obtained lignin-SiO 2 composite is modified by carbonazation, ball milling, magnesiothermic reduction and additives. Through these processes, a Si/C composite with excellent electrochemical properties is obtained and performs stable cycling performance with high specific capacity retention of 572 mA h g −1 at 1 A g −1 after 1000 cycles. This introduced method provides a potential for utilizing Si-rich biomass comprehensively and preparing desirable Si/C anode materials from Si-rich biomass derived lignin-SiO 2 composites.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2024
·
IF 5.3
Tongguo Huo,Dan Zhu,Jianxin Zheng,Yuan Lin,Yu Dai,Jian Wu
This study systematically investigated for the first time the effects of varying the temperature, pressure, C/Si molar ratio, and H 2 /Si molar ratio on β-SiC coatings produced via chemical vapor deposition (CVD) using the SiCl 4 –CH 4 –H 2 –N 2 system. Thermodynamic theoretical calculations were performed using the HSC Chemistry software. The temperature and C/Si molar ratio considerably affected the morphology, phase, and composition of β-SiC coatings. High-quality β-SiC coatings along the (111) crystal plane exhibiting a uniform surface, high density, low roughness, and good crystallinity were successfully synthesized at 1523.15 K and 200 Pa with a C/Si molar ratio of 1.0 and H 2 /Si molar ratio of 6.5. Additionally, when N 2 was used as the dilution gas instead of Ar, the resulting β-SiC coatings demonstrated reduced roughness, fewer free carbon, increased hardness (37.05 GPa vs. 39.19 GPa), enhanced modulus of elasticity (237.26 GPa vs. 264.24 GPa), and superior coating adhesion (16.48 MPa vs. 18.29 MPa).
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
OPTIK
·
2021
·
IF 2.443
Beiping Dong,Yanan Gao,Juncheng Liu
High transmittance and strong dust-removing film has a broad potential application prospect in architectural glass, solar photovoltaic glass, automotive glass, etc. In this paper, SnO 2 is used as the antistatic agent, and SiO 2 as the matrix. The effects of Sn/Si molar ratio on the structure and properties of the SnO 2 -SiO 2 film prepared on quartz glass substrate with sol-gel dipping were studied. The film was analyzed by X-ray diffractometer (XRD), Fourier transform infrared (FTIR) spectroscopy and Scanning electron microscopy (SEM). Ultraviolet-Visible-Near Infrared Spectrometer (UV–VIS–NIR) and Hall effect instrument tested the photoelectric properties. Falling dust experiment was used to determine the film’s dust-removing property. The results show that the SnO 2 -SiO 2 film is composed of nano particles of SnO 2 tetragonal rutile phase and amorphous SiO 2 , and has antistatic dust-removing property. With the increase of Sn/Si molar ratio, the crystallization quality and average grain size of the film increases, while the square resistance decreases continuously. The visible transmittance fluctuates with an amplitude of no more than 1.2%, and obtained the minimum value 87.246% at Sn/Si molar ratio of 2:1. Moreover, the film’s dust-removing performance improves continuously, which obtained the best, 50%, at Sn/Si molar ratio of 2:1.
研究领域:
材料科学
·
光学工程
·
表面科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）