CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Min Liu,Zhendong Yao,Wenqing Li,Jing Zhang,Chao Li,Xu Huang,Jiaguang Zheng,Liuting Zhang,Meiqiang Fan
Silicon is considered as a promising portable hydrolytic hydrogen production material due to its abundant raw materials, high theoretical capacity (1600 mL/g) and facile storage. However, the low hydrolysis activity and slow hydrolysis rate of silicon hinder its practical application. To address this issue, we introduced CaH 2 to form Si-based composites via a flexible ball milling method. The above composites showed ideal yield (1216 mL/g in 10 min), reaction conversion (95.5%) and fast hydrolysis kinetics (225 mL/(s·g)) in deionized water, which is one of the best hydrolysis performances of Si-based composites so far. The hydrolytic process can be divided into two steps: the splitting hydrolysis of CaH 2 and the continuous hydrolysis of Si. Combining the dynamic in-situ structural analysis with the analogue simulation, it can be confirmed that the formation of local high concentration alkali field is the key to promote the complete hydrolysis and achieve high yield and fast kinetics of the composites. The existence of lattice defects was proved and the adsorption of Si to hydroxide ion was proved by theoretical calculation. Our work provided a novel idea for the theoretical design of hydrolytic hydrogen production compounds and promoted the practical application of low cost and portable hydrolytic hydrogen production materials.
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高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
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2023
·Vol. 332
·期 11
·4477-4488
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IF 1.6
Zou Jin-Zhao,Xu Shi-Zhuan,Wang Peng,Cao Chang-Qing,Yan Chao,You Yan,Lu Jun-Qiang,Zhu Li-Bing,Zhu Zhi-Yong,Lin Jun
A solid-phase metallurgy combined with spark plasma sintering technology was used to prepare U 3 Si 2 pellets. The thermal conductivity and oxidation behavior of the pellets were studied. The pellets were highly dense (> 98% theoretical density) and had an ultra-high phase purity. The thermal conductivity of the U 3 Si 2 pellets increased linearly with temperature from 300 to 973 K. By further annealing the pellets at 300 °C in air for two hours, the oxidation onset temperature was increased from 490 to 520 °C. A mechanism of pore passivation was proposed to account for the enhanced oxidation resistance.
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JOURNAL OF ALLOYS AND COMPOUNDS
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2021
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IF 5.316
Mingwei Liang,Weijing Wang,Yi Jiang,Chenyang Liao,Qin Long,Xuefei Lai,Li Liao
The commercial application of silicon is still impeded by poor conductivity and significant volume change. In this work, a C@Si@G composite was synthesized by a facile chemical solution reaction and carbonization procedure with cocoon silk as a natural carbon source. This composite has a sandwich structure, where Si nanoparticles as a sandwich middle layer and graphene (G) as an out layer. And it possesses the advantages of flexible, nitrogen-doped and is environmentally friendly. The optimized C@Si@G-15 composite is used as a self-supporting anode without a current collector, and it shows a reversible discharge capacity of 972 mAh g −1 after 120 cycles at 1 A g −1 and a relatively high capacity of 1070 mAh g −1 after 300 cycles at 200 mA g −1 , demonstrating the effect of coating the N-doped carbonized silk and the graphene synergistically to improve electrical connectivity and to constrain the pulverization of Si nanoparticles. Hence, it delivers great potential for application on wearable devices .
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ACS Nano
·
2021
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IF 15.881
Zehang Zhou,Quancheng Song,Bingxue Huang,Shiyi Feng,Canhui Lu
The development of modern electronics has raised great demand for multifunctional materials to protect electronic instruments against electromagnetic interference (EMI) radiation and ice accretion in cold weather. However, it is still a great challenge to prepare high-performance multifunctional films with excellent flexibilty, mechanical strength, and durability. Here, we propose a layer-by-layer assembly of cellulose nanofiber (CNF)/Ti3C2Tx nanocomposites (TM) on a bacterial cellulose (BC) substrate via repeated spray coating. CNFs are hybridized with Ti3C2Tx nanoflakes to improve the mechanical properties of the functional coating layer and its adhesion with the BC substrate. The densely packed hierarchical structure and strong interfacial interactions endows the TM/BC films with good flexibility, ultrahigh mechanical strength (>250 MPa), and desirable toughness (>20 MJ cm–3). Furthermore, benefiting from the densely packed hierarchical structure, the resultant TM/BC films present outstanding EMI shielding effictiveness of 60 dB and efficient electro-/photothermal heating performance. Silicone encapsulation further imparts high hydrophobicity and exceptional durability against solutions and deformations to the multifunctional films. Impressively, the silicone-coated TM/BC film (Si-TM/BC) exhibits desirable low voltage-driven Joule heating and excellent photoresponsive heating performance, which demonstrates great feasibility for efficient thermal deicing under actual conditions. Therefore, we believe that the Si-TM/BC film with excellent mechanical properties and durability holds great promise for the practical applications of EMI shielding and ice accretion elimination.
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PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zhiwei Yang,Lang Qiu,Mengke Zhang,Yanjun Zhong,Benhe Zhong,Yang Song,Gongke Wang,Yuxia Liu,Zhenguo Wu,Xiaodong Guo
SiO 2 is one of the critical raw materials for preparing Si anode. The direct use of porous Si made from SiO 2 in LIBs is challenging. Although carbon cladding can improve the cycling performance of Si anode materials made from SiO 2 , the surface coating cannot address the comminution inside the material during repeated volume deformation. For the first time, we prepared an in-situ doped Si/carbon anode material that uses SiO 2 and CO 2 as Si and carbon sources and Mg as the reduction medium (Mg 2 Si + CO 2 → MgO + Si + C). The in situ embedded carbon completes the nanosizing of Si (less than50 nm) and forms a three-dimensional (3-D) carbon network that enhances electrical conductivity and acts as a buffer layer. After 500 cycles at 0.5 A g −1 , the discharge specific capacity is 912 mAh g −1 , and the capacity still has 1487 mAh g −1 even at 4 A g −1 . The simple method of preparing Si/carbon composite material in situ provides a new idea for modifying Si-based anode material and provides a valuable reference for carbon doping.
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INORGANIC CHEMISTRY
·
2021
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IF 5.165
Peng Zhang,Shen-Jing Ji,Dong Zhang,Huai-Guo Xue,Nian-Tzu Suen
Recently, it has been reported that the enstatite chondrite (EC) meteorite may contain enough hydrogen to provide a plausible explanation for water’s initial existence on Earth. Perryite mineral is one of the key components of EC, but its detailed chemical composition and phase width remain elusive compared with other minerals found in EC. Therefore, we embark on a series of investigations of the synthesis, crystal structure, and electronic structure of the synthetic perryite mineral (NixFe1–x)8(TyP1–y)3 (T = Si and Ge; 1 ≥ x, y ≥ 0). Its crystal structures were established based on single-crystal and powder X-ray diffraction techniques. It is realized that its structural and phase stabilities are highly dependent on the nature of the doping element (i.e., Fe and Si). The inclusion of Si and Fe elements can greatly alter the bonding scheme near the Fermi level (Ef), which is vital to the phase stability and accounts for the chemical composition of the natural perryite mineral (quaternary compound) in EC meteorites. Furthermore, this phase exhibits good electrocatalytic activity toward the hydrogen evolution reaction (HER). The best and the worst HER performances are for the Ni8Ge2P and Ni8Si2P samples, respectively, which suggests that the long bond length and high polarity of the covalent bond are the preferred criteria to enhance the electrocatalytic HER in this series.
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高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Haitang Yang,Yanping Yang,Xueqiang Cao,Xiaozhong Huang,Yang Li
A Yb 2 SiO 5 /mullite/Si tri-layer environmental-barrier-coating (EBC) were coated on SiC f /SiC substrates via Air Plasma Spraying (APS). The thermal cycle tests (TCT) were conducted under thermal corrosive condition of vapor-oxygen (50 vol% H 2 O and 50 vol% O 2 ) with thermal shock from 1200 °C to 200 °C. Microstructures, weight loss and bonding strength of the samples were systemically investigated after 101, 396, 606 and 700 TCT cycles respectively. The results show that the corner of the tri-layer coating peel off from the sample with weight loss of 1.3% after 700 TCT cycles. The bonding strength between substrate and tri-layer coatings gradually decreases to 6.79 MPa (approximately 55.2% of virgin specimens) after 700 cycles due to thermal shock induced cracks distributed horizontally within Si layers and between Si layer and outer layers.
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高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2021
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IF 8.067
Sainan Liu,Hongtai Shen,Jiawei Xu,Xiaojun Zhou,Jianfei Liu,Zhenyang Cai,Xiaojun Zhao,Lairong Xiao
To develop an ultra-high-temperature resistant coating for a reusable thermal protection system, the preparation of a tantalum-based MoSi 2 -Mo coating by a new two-step process of multi-arc ion plating and halide activated pack cementation is presented. The coating has a dense structure and is well compatible with the tantalum substrate, which can be thermally shocked from room temperature to 1750 °C for 360 cycles without failure. The mechanism of the coating’s excellent resistance to high-temperature thermal shocks is that a strong-binding gradient interface and a dense SiO 2 oxide scale with good oxygen resistance are formed by the high-temperature self-diffusion of Si.
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2020
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IF 4.495
Qi Wang,Ming-hao Li,Guo-qing Chen,Xue-song Fu,Wen-long Zhou
Adjusting the growth kinetics of the interfacial compound layers may be a feasible way to enhance joint properties or service performance. In this study, the textured Ti 3 SiC 2 was obtained by hot-deforming the sintered Ti 3 SiC 2 (TSC), and the effects of the texture orientation on the interfacial microstructural evolution and growth kinetics of the interfacial compounds in the diffusion bonded TiAl/Ti 3 SiC 2 joints were investigated. The texture orientation of Ti 3 SiC 2 had little effect on the interfacial microstructural evolution but had a significant effect on the growth kinetics. When bonded at the same temperature, the growth rate of the interfacial compound layers in the TiAl/TSC ∥ joint (TSC ∥ , TSC ⊥ : Ti 3 SiC 2 with [0001] texture orientation parallel, perpendicular to the bonded seam) was fastest; which was slowest in the TiAl/TSC ⊥ joint and was in the middle in the TiAl/TSC joint. The highest shear strengths of the three different joints were similar (about 54 MPa).
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高影响因子
ACS Applied Energy Materials
·
2020
·
IF 4.473
Lijing Yan,Huiwen Zhang,Zeheng Li,Xuehui Gao,Hongbo Wang,Zhan Lin,Min Ling,Chengdu Liang
Nanostructured silicon has been regarded as a promising next-generation anode material for high energy density lithium-ion batteries. However, costly synthesis methods and low initial coulombic efficiency are still two major challenges for its practical application. Herein, secondary submicron silicon materials composed of nanoparticles are successfully prepared by a simple, low-cost, and efficient high energy mechanical milling method. The initial coulombic efficiency of the as-prepared silicon anode reaches 89.14% with a first discharge specific capacity of 3233 mA h g–1 at 100 mA g–1. In light of a low-cost precursor, facile approach, and high initial coulombic efficiency, this work may provide guidance and enlightenment in synthesizing nanostructured silicon with a secondary structure as anode materials for lithium-ion batteries.
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高影响因子
ChemElectroChem
·
2020
·Vol. 7
·期 21
·4423-4430
·
IF 4.154
Chao Yuan,Dujiang Lu,Yongling An,Xiufang Bian
Graphical Grind and coat : A novel nanocomposite of amorphous carbon-coated Si nanosphere and ZIF-67 derived hollow porous cobalt sulfide/carbon polyhedron is fabricated by a simple grinding process. ZIF-67 derived Co 9 S 8 /C can serve as a buffer to alleviate the volume expansion of Si. The vast conductive carbon layer originated from Co 9 S 8 /C and Si@C plays a key role in facilitating the electron transfer and lithium ion transport kinetics. Si@C−Co 9 S 8 /C anodes deliver improved electrochemical performance. Silicon (Si) is regarded as one of the most promising anode materials for lithium-ion batteries (LIBs) due to its high capacity and low working voltage. However, dramatic volume expansion and inferior electrical conductivity greatly impede the commercial use of Si anodes. Herein, we design and synthesize a novel nanocomposite of Si nanosphere coated by carbon (Si@C) and hollow porous Co 9 S 8 /C polyhedron (Si@C−Co 9 S 8 /C). The hollow porous Co 9 S 8 /C derived from Co-based zeolitic imidazolate framework can serve as a buffering matrix to accommodate the volume expansion of Si, which is beneficial to improve the cycle performance. The vast conductive carbon layer originated from Co 9 S 8 /C and Si@C plays a key role in accelerating the electron transfer and lithium ion transport kinetics, which can significantly enhance the rate performance. As a result, the Si@C−Co 9 S 8 /C anodes deliver stable cycle performance with a reversible capacity of 1399 mA h g −1 after 200 cycles at 100 mA g −1 , improved rate performance and high Coulombic efficiency. This simple route sheds light on designing Si-based composites for LIBs anodes.
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JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Rui Fan,Ying Huang,Xiaopeng Han,Xuanyi Peng
To obtain high performance composites for thermal management fields, we adopt a new route to prepare the graphite flakes (Gf)/aluminum (Al) composites via vacuum pressure infiltration process. In this study, aluminum nitride (AlN) particles were used as supporting particles to obtain infiltration pathways for the penetration of the molten Al matrix. Gf, starch , urea and AlN were mixed evenly in the mass ratio of 1: 0.035: 0.058: 0.3 and then sintered at 330 °C to prepare porous preforms. It was observed that these substances had excellent chemical compatibility using characterization equipment. The improvement of the thermal transfer and mechanical properties of the composites for silicon coating was also studied. When the volume fraction of graphite was about 54%, compared with the samples without coating, the samples with SiC coating displayed an excellent thermal conductivity (TC) of 467.8 W/m·K and a promising bending strength of 58.8 Mpa, which increased about 82.1 and 238.0%, respectively. The coefficient of thermal expansion (CTE) of composites also decreased about 23.3% from 2.19 × 10 −5 K −1 to 1.68 × 10 −5 K −1 from room temperature to 380 °C.
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高影响因子
危险品化学品经营许可证（带存储）