JOURNAL OF ALLOYS AND COMPOUNDS
·
2014
·
IF 2.726
Dong Yan,Ying Bai,Caiyan Yu,Xiaoge Li,Weifeng Zhang
Nanoscaled Si is successfully wrapped with different contents of nano-TiO 2 (the molar ratios of Si/TiO 2 composites are 1:1, 1:2, 1:3, 1:4 and 1:5, respectively) to form a novel pineapple structure. X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM) are utilized to characterize the structure, component, chemical environment and morphology of the composite. The investigation in cycling performances demonstrates that Si/TiO 2 with molar ratio of 1:4 exhibits the best cycling stability, with specific capacity of 593 mA h g − 1 after 50 cycles at 0.1 C, much higher than those of the other composites and the pristine material. Cyclic voltammetry (CV) profiles are also measured and compared. It is believed that the outside TiO 2 particles act as buffer against the huge volume change of Si during repeated alloying and de-alloying, which explains the improved electrochemical performances.
✓ 已验证
产品关联
DOI
高影响因子
INORGANICA CHIMICA ACTA
·
2013
·
IF 1.687
Yan-Jing Gu,Bing Yan
The synthesis of organics 9-hydroxyphenalenone (HPO), 2-methyl-9-hydroxyphenalenone (MHPO), 6-hydroxybenz[de]anthracen-7-one (HBAO), 5-amino-1,10-phenanthroline (phen-NH 2 ) and its functionalized mesoporous MCM-41 by covalent band are reported, as well as those of Europium (III) hybrid mesoporous materials, EuL 3 phen-MCM-41 (L = HPO, MHPO, HBAO). The photoluminescence and microstructural properties are characterized, and the XRD and BET results revealed that all of these hybrid materials have uniformity in the mesostructure. It is worth noting that the excitation spectra of these hybrid materials have a broad absorption, which occupies from UV to visible region (250–475 nm). Upon ligand-mediated excitation with the visible light, the low efficient energy transfer exhibit between the organic ligands and europium(III) ion under visible excitation, but the maximum wavelength (456 nm/457 nm/451 nm) located at blue light region, which is in consistent with the blue LED light, then might be a feasible alternative in producing time-resolved luminescence under LED-excitation.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2013
·
IF 4.675
Lu Yue,Lingzhi Zhang,Haoxiang Zhong
Carboxymethyl chitosan (C-chitosan) is investigated as a new water soluble binder for Si anode of Li-ion batteries. The Fourier transformation infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) measurements reveal that the strong hydrogen bonding is formed between the hydroxylated Si surface and the polar groups (–OH, –COOH and –NH 2 ) of C-chitosan. The Si/C-chitosan anode (Si:carbon black:C-chitosan = 62:30:8 in weight ratio) exhibits a high first discharge capacity (4270 mAh g −1 ) with a first coulombic efficiency of 89%, and maintains a capacity of 950 mAh g −1 at the current density of 500 mA g −1 over 50 cycles.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2024
·
IF 8.1
Wenhui Geng,Xinmeng Hu,Qinhua Zhou,Yinhang Zhang,Bin He,Zhiliang Liu,Kuikui Xiao,Dong Cai,Shuo Yang,Huagui Nie,Zhi Yang
Silicon (Si) has been regarded as a candidate for high-energy-density lithium-ion batteries (LIBs) because of its excellent specific capacity. Binders, as an essential component in Si anodes, play a key role in enhancing the electrochemical performance of LIBs. In this study, a multifunctional binder named LP19 simultaneously possessing high electron conductivity, high Li-ion conductivity as well as ameliorative mechanical performances was synthesized by assembling the lithiated PAA (LiPAA) and highly conductive PEDOT:PSS molecules. The lithiation treatment of PAA is conducive to the transport of lithium ions, while the double conductive network constructed by conductive PEDOT:PSS and Super P guarantees the stable electric connectivity during lithiation and delithiation processes. Moreover, the optimization of the internal configuration of the molecules realizes the structural and cycling stability of the Si anode. As a consequence, the Si anode utilizing this binary and multifunctional conductive binder demonstrated pronounced cycling stability (2165 mAh g −1 after 200 cycles) and rate performance (1750 mAh g −1 at 8.0 A g −1 ). This work provided a novel design strategy of polymeric binders to promote progress toward high-performance LIBs.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Yingjun Qiao,Yuxin Hu,Zhiqiang Qian,Meizhen Qu,Zhong Liu
The yolk-shell architecture offers a promising solution to the challenges of silicon (Si) anodes in lithium-ion batteries (LIBs), particularly in addressing the significant volume changes that occur during charge and discharge cycles. However, traditional construction methods often rely on sacrificial templates and acid or alkali etching, which limits industrial applicability. In this work, we successfully constructed a silicon/carbon (Si/C) composite with a multicore yolk-shell structure using scalable spray drying technology and in-situ growth of metal–organic frameworks (MOFs) at room temperature. By controlling the spray drying parameters and the size of the MOF, we achieved a controllable adjustment of cavity size and shell integrity without the need for sacrificial templates, facilitating large-scale preparation. Electrochemical characterization shows that the composites exhibit impressive performance, achieving a reversible specific capacity of 1,054.5 mAh g −1 after 100 cycles at 0.5 A g −1 , and retaining 734.8 mAh g −1 after 400 cycles at 1 A g −1 . Moreover, finite element analysis (FEA) revealed another reason why the yolk-shell structure improves the performance of Si anodes: the presence of cavities promotes ion diffusion processes. This study provides a new synthetic paradigm for preparing Si-C composite materials with yolk shell structure and offers new insights into the improvement mechanism of this structure.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Defence Technology
·
2024
·
IF 5
Zhanjun Yang,Hao Liu,Li Mi,Xiaoqian Wang,Oisik Das,Zhong xuan Han,Lin Jiang
To investigate the differences in combustion and energy release characteristics of metastable intermolecular composite materials composed of aluminum alloys and polyvinylidene fluoride (PVDF) with different compositions, two types of alloys were selected: Al-Mg and Al-Si. Pure aluminum powder of the same size was also chosen for comparison. The PVDF-coated metal particle composites and the mixtures of PVDF with metal particles were prepared using electrospray (ES) and physical blending methods (PM), respectively. A systematic study was conducted on the morphology, compositional structure, combustion performance, energy release characteristics, and thermal reactivity of the fabricated composites and their combustion products through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), combustion performance experiments, closed vessel pressure tests, and simultaneous thermogravimetric-differential scanning calorimetry (TG-DSC). The experimental results indicated that the PVDF-coated metal particles prepared by the electrospray method exhibited a distinct core-shell structure, with the metal particles in close contact with the PVDF matrix. Compared to the PM blended materials, the ES composites demonstrated superior combustion performance and energy release characteristics during combustion. Analysis of different metal fuel systems under identical preparation conditions revealed that Al-Mg and Al-Si fuels modulate the combustion and energy release properties of aluminum alloy-PVDF MICs through two distinct pathways.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2024
·Vol. 20
·期 50
·2406489
·
IF 13
Yijun Gao,Shanshan Song,Fei He,Xianglong Kong,Zhong Xiao,Xianchang Cui,Linbo Cao,Yumeng Zhang,Zhiliang Liu,Piaoping Yang
Silicon (Si) has attracted considerable attention as a promising alternative to graphite in lithium-ion batteries (LIBs) because of its high theoretical capacity and voltage. However, the durability and cycling stability of Si-based composites have emerged as major obstacles to their widespread adoption as LIBs anode materials. To tackle these challenges, a hollow core–shell dodecahedra structure of a Si-based composite (HD-Si@C) is developed through a novel double-layer in situ growth approach. This innovative design ensures that the nano-sized Si particles are evenly distributed within a hollow carbon shell, effectively addressing issues like Si fragmentation, volume expansion, and detachment from the carbon layer during cycles. The HD-Si@C composite demonstrates remarkable structural integrity as a LIBs anode, resulting in exceptional electrochemical performance and promising practical applications, as evidenced by tests in pouch-type full cells. Notably, the composite shows outstanding cycling stability, retaining 85% of its initial capacity (713 mAh g −1 ) even after 3000 cycles at a high current rate of 5000 mA g −1 . Additionally, the material achieves a gravimetric energy density of 369 W h kg −1 , showcasing its potential for efficient energy storage solutions. This research signifies a significant step toward realizing the practical utilization of Si-based materials in the next generation of LIBs.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Qiang Zhang,Hongjuan Zhao,Xingyu Liu,Rui Li,Tian Xia,Yue Ma,Yuren Wang,Kang Chen,Jiujiang Wang,Penghui Zeng,Honghai Liu,Chaowei Liu,Xionghou Gao,Chunming Xu,Baojian Shen
It's a dream to make zeolites more stable so as to keep the activity and stability of the catalyst. Phosphorus modification is an effective method, however, the known post-modification predominantly presents as non-framework P, and the P-loss is a big trouble in application. We have discovered that in the reaction of PCl 3 or SiCl 4 + PCl 3 with NaY zeolite, a portion of P enters the framework of the zeolite, forming a PO 4 -AlO 4 structure. Further investigations revealed that P cannot be incorporated into the framework through P for Al isomorphous substitution, but rather through isomorphous substitution with Si(4Al). PCl 3 exhibits two effects in reaction: at lower quantities, it mainly undergoes isomorphous substitution with Si(4Al); at higher quantities, it leads to zeolite dealumination generating aluminum vacancies, which disrupt the zeolite framework or promotes Si for Al isomorphous substitution. After hydrothermal aging at 800 °C for 4 h, the stable presence of framework PO 4 -AlO 4 implies that the weakest site Si(4Al) becomes the more stable site P(4Al) in the Y zeolite framework. Compared with the JPY (prepared by impregnating (NH 4 ) 2 HPO 4 solution to high silica Y zeolite) sample, after 10 cycles of hydrothermal and water washing treatment, the P 2 O 5 loss rate of DPY (prepared by SiCl 4 + PCl 3 with NaY) zeolite ranged from 0.4 % to 3.5 %, significantly lower compared to the range of 18.7 % to 25.9 % observed in the JPY sample. This indicates that in DPY zeolite, the interaction between P and the zeolite is stronger and less prone to loss. Moreover, P is more uniformly distributed on the surface and bulk phase of DPY than JPY sample.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
ECS Journal of Solid State Science and Technology
·
2025
·
IF 2.2
zehao Yue,Chong Luo,Chenwei Wang,Jianwei Zhou,Wenbo Liu
As a third-generation semiconductor, silicon carbide (SiC) is extensively utilized in photovoltaic power generation, 5G communication, and new energy vehicles. However, the current method for the chemical mechanical polishing of SiC exhibits low material removal rates (MRRs) and suboptimal surface quality postpolishing. To address these challenges, we developed in this study a slurry that reduced the surface roughness of SiC–Si facets from 3.55 to 0.048 nm, achieving a MRR of 169 nm/h. The core removal mechanism involves a V2O3-catalyzed Fenton-like reaction to convert H2O2 into ·OH radicals for the rapid oxidation of the SiC–Si facets, which produces a softer oxide layer that is subsequently removed by the mechanical action of abrasives. Consequently, ultrasmooth SiC–Si facets with no visible scratches were obtained. On the basis of ultraviolet–visible spectral photoluminescence and X-ray photoelectron spectroscopy analyses, we propose a catalytic oxidation mechanism leading to high-quality surfaces on the SiC–Si facets. In addition, the identification of the active sites of the reaction by means of simulations further validates the polishing mechanism.
研究领域:
材料科学
·
半导体技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2024
·
IF 5.4
Bo Pei,Yinmei Li,Shenhui Ma,Yuyu Bu
The photoelectrochemical (PEC) water splitting performance of Si-based PEC devices is usually restricted by low stability and weak photogenerated carrier transport ability. Herein, a micropyramid array structure (p-SiMPs)/p-Cu2O/PhC2Cu/Pt photocathode device with a p-p-n heterojunction structure is developed. In this tandem PEC device, a p-p heterojunction of p-SiMPs/p-Cu2O is achieved, endowing a higher interface electric field and stronger energy of photoinduced electrons for PEC water reduction. In addition, a stable n-type PhC2Cu protective layer is prepared on the surface of the PEC device by the photoassisted polymerization method, which can improve the stability of PEC water reduction largely. After Pt cocatalytic layer deposition, the p-SiMPs/p-Cu2O/PhC2Cu/Pt tandem photocathode can achieve a saturation photocurrent density of −30 mA/cm2 at −0.9 V (vs RHE) and a photocurrent threshold voltage of −0.1 V for water reduction. This work provides a silicon-based p-p-n heterojunction tandem structure for the PEC water splitting; meanwhile, it indicates that PhC2Cu is a potential material to improve the stability of silicon-based PEC devices.
研究领域:
材料科学
·
能源转换技术
·
半导体物理
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Xiaonan Huang,Yulian Chen,He Jiang,Jiajun Hu,Xi Guo,Yanjuan Zhang,Jianzhang Li,Weisheng Sun,Yi Zhang
The development of melamine-formaldehyde (MF) resin-impregnated paper has great significance in the decoration and construction industries. However, the MF-impregnated paper is prone to cracking and burning due to the inherent brittleness and poor flame retardancy of MF resin, restricting its wide application. Herein, we report a hyperbranched polysiloxane (HBPSi@EP) containing a flexible Si–O–C skeleton and tailored terminal epoxy using a simple, low-cost, and easily controlled ester exchange strategy to modify MF resin for fabricating high-performance and multifunctional impregnated paper. The break elongation of MF/HBPSi@EP impregnated paper increased by 186.5% since the energy dissipation of the hyperbranched structure and lubrication of the Si–O–C skeleton enhance its toughness. The tough MF/HBPSi@EP impregnated paper displayed outstanding cracking resistance during the thermal–cooling cycle. Meanwhile, the tensile strength of MF/HBPSi@EP impregnated paper reached 10 MPa, owing to the formation of a dense cross-linked structure by the hyperbranched epoxy in the HBPSi@EP. Notably, this impregnated paper exhibited good flame retardancy (B1-level in GB 8624-2012), cigarette burn resistance (Level 4 in GB/T 17657-2013), and wear resistance (1305.5 r). This facile and effective strategy can promote the development of tough, strong, and versatile coatings, film materials, and multifunctional composites.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-14
·
IF 15.7
Chen Wei,Wang Danhao,Wang Weiyi,Liu Xin,Liu Yuying,Wang Chao,Kang Yang,Fang Shi,Yang Xudong,Gu Wengang,Luo Dongyang,Luo Yuanmin,Qu Zongtao,Zuo Chengjie,Kang Yi,Cheng Lin,Yan Wensheng,Hu Wei,Long Ran,He Jr-Hau,Liang Kang,Liu Sheng,Xiong Yujie,Sun Haiding
The development of an efficient and durable photoelectrode is critical for achieving large-scale applications in photoelectrochemical water splitting. Here, we report a unique photoelectrode composed of reconfigured gallium nitride nanowire-on-silicon wafer loaded with Au nanoparticles as cocatalyst that achieved an impressive applied bias photon-to-current efficiency of 10.36% under AM 1.5G one sun illumination while exhibiting stable PEC hydrogen evolution over 800 h at a high current density. Specifically, by tailoring the GaN nanowires via a simple alkaline-etching step to expose the inner (10 \(\bar{1}\bar{1}\) ) facets, we achieve a highly coupled semiconductor nanowire-cocatalyst heterointerface with strong electron interaction. The strongly coupled reconfigured GaN nanowire/Au heterointerface not only optimizes the electronic structure of Au nanoparticles to form abundant highly active interfacial regions, eventually realizing superior hydrogen evolution activity but also enables GaN nanowires to provide a stronger anchoring effect for Au nanoparticles, preventing the detachment of Au nanoparticles during the intense hydrogen evolution process. The proposed photoelectrode offers a feasible structure for overcoming the efficiency-reliability bottleneck of PEC devices for producing clean hydrogen fuel.
研究领域:
材料科学
·
能源转换
·
光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子