ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Lin Wang,Xiaohang Pan,Yong Zhang,Yunlei Zhong,Xu Zhang,Zhen Zhang,Alei Li,Pin Zhao,Qing Guo,Yunfei Li,Hui Zhang,Leilei Xu,Yujia Wang,Mengjiao Han,Xiuliang Ma,Lixing Kang
Ferroelectricity in ultrathin 2D materials has garnered significant attention owing to its potential applications in nonvolatile memory, nanoelectronics, and optoelectronics. However, the exploration of ferroelectricity in materials possessing inherent centrosymmetric or mirror symmetry, particularly in the 2D domain, remains limited. In this study, the chemical vapor deposition (CVD) technique is utilized to synthesize ultrathin Bi 2 WO 6 (BWO) nanoflakes, revealing robustly intercorrelated out-of-plane (OOP) and in-plane (IP) ferroelectric polarization. The measured ferroelectric phase transition temperature of ultrathin BWO nanoflake is ≈800 K. The emergence of OOP ferroelectricity in BWO nanoflake is ascribed to the displacement of oxygen vacancies between neighboring asymmetric sites, leading to the disruption of local structural mirror symmetry and the alignment of dipole moments. Moreover, the IP and OOP ferroelectric responses are modulated by distinct maximum bias voltages. This investigation offers novel insights into the advancement of 2D ferroelectrics with elevated Curie temperatures.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Ying Chen,Yuan Gao,Yongsheng Xu,Yuanlin Jing,Wenchao Peng
Nitrogen doped carbon materials have great potential in the peroxymonosulfate based advanced oxidation processes due to their high efficiency. However, because of the limitation of prepared method, the doped N species are usually uncontrollable. In this work, a series of metal-free N-doped carbon materials are synthesized by chemical vapor deposition (CVD) with a CaO template and through regulating the deposition temperature we achieve the gradient control of the edged-N species. Taken phenol as the pollutant probe, the catalytic performances of N-doped carbon material are investigated, and 700 °C is determined to be the optimal deposition temperature for carbon material with a reaction rate constant of 0.335 min −1 . After the analysis of kinetics and the N species, we demonstrate that the content of pyrrolic N has an exponential relationship with the activity. Radicals quenching experiments, electron paramagnetic resonance and electrochemical test are also employed to verify that O 2 •– , 1 O 2 , and direct electron transfer are the dominated reactive oxidation species rather than typic hydroxyl and sulfate radicals. Overall，this doped strategy through CVD give a new insight of controlling doped species in carbon materials preparation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Jun Xie,Mei Zhao,Youqing Dong,Chao Zou,Shuang Pan,Quanlong Xu,Yun Yang,Shun Wang,Lijie Zhang
The all-inorganic lead-free perovskite Cs 2 SnI 6 has gained considerable research attention due to its outstanding characteristics, including non-toxicity, robust stability, and superior photoelectric performance. In this research, we employed a simple yet robust chemical vapor deposition technique to successfully grow ultra-thin 2D Cs 2 SnI 6 flakes on a mica substrate, achieving a minimal thickness of just 8 nm and a significant lateral size of up to 48 μm. The obtained 2D Cs 2 SnI 6 flakes displayed an extended photoluminescent lifetime of approximately 1.44 ns and exceptional stability, maintaining their crystal structure intact over a period of 60 days. The photodetectors fabricated from Cs 2 SnI 6 flakes demonstrated a broad ultraviolet to near-infrared response range (365–1342 nm), with a responsivity of up to 6.25 × 10 5 A W −1 . They additionally displayed rapid rise and decay times of 31.32 ms and 72.42 ms, respectively, with an external quantum efficiency reaching as high as 1.92 × 10 6 %, and a detectivity achieving 1.27 × 10 11 Jones. This research serves as a critical step forward in enabling the facile yet robust synthesis of stable, all-inorganic ultra-thin lead-free perovskites, paving the way for innovation in environmentally friendly optoelectronic devices.
研究领域:
材料科学
·
光电技术
·
纳米科技
✓ 已验证
产品关联
DOI
高影响因子
Coatings
·
2024
·Vol. 14
·期 11
·1473
·
IF 2.9
Bin Zhu,Wenjun Li,Wu Tang,Hui Tang
With the increasing demand for renewable energy and sustainable technologies, lithium-ion batteries (LIBs) have become crucial energy storage components. Despite the promising properties of the high capacity and stability of TiO2, its large-scale application as an anode for LIBs is hindered by challenges like poor conductivity and volumetric changes during cycling. Here, a rutile TiO2composite material with a thinned carbon coating (TiO2@TC) was synthesized through chemical vapor deposition (CVD) and a subsequent annealing process, which significantly improved the reversibility, cycling stability, and rate performance of the TiO2anode materials. The thickness of the carbon layer on TiO2was precisely controlled and thinned from 4.2 nm to 1.9 nm after secondary annealing treatment, leading to a smaller steric hindrance and an improved conductivity while serving as protective coatings by preventing the electrochemical degradation of the TiO2surface and hindering volumetric changes during cycling. The resulting TiO2@TC with the thin carbon layer demonstrated a high specific capacity of 167 mAh g−1at 0.5 C in Li-based half cells, which could stably run for 200 cycles with nearly 100% capacity retention. The thin carbon layer also contributes to an improved rate performance of 90 mAh g−1at even 20 C. This work provides an innovational strategy for improving the conductivity and volumetric changes during the cycling of TiO2anodes.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2024
·
IF 8.1
Patrick Ryan Galligan,Hongwei Liu,Guang Wang,Mohsen Tamtaji,Yaxuan Li,Tsz Wing Tang,Yanguang Zhou,Zhengtang Luo
Lightweight boron carbon nitride foams which are a hybrid of graphene and hexagonal boron nitride (hBN), are produced using the nickel template method and remain freestanding after the etching of nickel without the stabilization of a polymer during etching. Chemical vapor deposition (CVD) precursors with varying carbon content were utilized, but only a 10% range of carbon atomic percentage variation is observed in the resulting boron carbon nitride foams due to the high carbon solubility of nickel. However, the cooling rate during the CVD process has a much more significant effect on the carbon content. Moreover, a 6.5-fold increase in resistivity is observed for our foams compared to a graphene foam with an overall trend of decreasing resistance with increasing carbon content. Furthermore, when the foam is infiltrated with epoxy to form a composite at 0.3% volumetric percentage concentration, there is a 27% increase in the thermal conductivity over hBN foam composites. These foams are suitable to use as a substitute for graphene foams when a lower electrical conductivity is desired and could potentially be used as a thermal interface material if a higher pore density nickel template is utilized.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 12
·期 3
·1958-1966
·
IF 6.97
Peng Yang,Yabing Shan,Jing Chen,Garel Ekoya,Jinkun Han,Zhi-Jun Qiu,Junjie Sun,Fei Chen,Haomin Wang,Wenzhong Bao,Laigui Hu,Rong-Jun Zhang,Ran Liu,Chunxiao Cong
Monolayer MoS2 is a direct bandgap semiconductor which is believed to be one of the most promising candidates for optoelectronic devices. Chemical vapor deposition (CVD) is the most popular method to synthesize monolayer MoS2 with a large area. However, many defects are always found in monolayer MoS2 grown by CVD, such as sulfur vacancies, which severely degrade the performance of devices. This work demonstrates a concise and effective method for direct growth of high quality monolayer MoS2 by using SiO2/Si substrates pretreated with sulfur vapor. The MoS2 monolayer obtained using this method shows about 20 times PL intensity enhancement and a much narrower PL peak width than that grown on untreated substrates. Detailed characterization studies reveal that MoS2 grown on sulfur vapor pretreated SiO2/Si substrates has a much lower density of sulfur vacancies. The synthesis of monolayer MoS2 with high optical quality and low defect concentration is critical for both fundamental physics studies and potential practical device applications in the atomically thin limit.
研究领域:
材料科学
·
光学
·
半导体物理
✓ 已验证
DOI
PubMed
高影响因子
ChemNanoMat
·
2021
·Vol. 7
·期 3
·323-327
·
IF 3.154
Yuxi Guo,Lixing Kang,Shaojia Yu,Jiefu Yang,Xiaofei Qi,Zhiyong Zhang,Zheng Liu
Graphical Large-scale 2D CrTe nanoflakes with a size of ∼250 μm were successfully synthesized via a chemical vapor deposition process, which used mixed compounds (Cr: CrCl 3 ⋅ 6H 2 O: Te) as Cr source and excessive Te in the upstream as Te source. The Te in the mixed compounds decreases the melting point of the mixed compounds and promotes the nucleation and growth of CrTe nanoplates, which leads to large-scale growth of CrTe nanoflakes. Recently, 2D magnetic materials have attracted much attention due to their potential applications in spintronic devices. Chromium telluride (CrTe) flakes have been reported for hard magnetism with a strong perpendicular anisotropy. However, the synthesis of large-scale CrTe nanoflakes on SiO 2 /Si substrate is still a challenge. Here, we report the synthesis of large-scale CrTe nanoflakes with a size of up to ∼250 μm on a SiO 2 /Si substrate via chemical vapor deposition (CVD). Our work demonstrated an effective pathway to synthesize large-scale 2D transition metal tellurides.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Jianjie Qin,Chengguo Wang,Zhiqiang Yao,Ziming Ma,Xuanhao Cui,Quan Gao,Yanxiang Wang,Qifen Wang,Huazhen Wei
The continuous growth of carbon nanotubes (CNTs) was realized on the surface of moving carbon fiber substrate by chemical vapor deposition (CVD). The changes in the microstructure of the catalyst precursor reduction and the catalyzed growth of CNTs during the continuous process were tracked, and the factors causing the deterioration of mechanical properties and the increase of tensile strength were discussed. The formation of catalyst nanoparticles invaded the surface of carbon fibers, cutting off the continuous graphite layer and causing a loose graphite structure. With the catalyzed growth of CNTs which have good crystallinity, the graphite cross-links between their roots and the fiber surface repaired the defects generated by the catalyst. Due to the repair of surface defects by carbon source decomposition and interface CNTs during CVD process, the tensile strength of CNTs/carbon fiber reinforcement is increased by 8.55% compared with the raw carbon fibers. This research helps to grow CNTs uniformly on the surface of carbon fibers to prepare a large number of composite reinforcements, and can maintain or even improve the overall mechanical properties.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS & DESIGN
·
2020
·
IF 6.289
Yiqun Zhang,Yaqiang Dong,Bang Zhou,Qiang Chi,Liang Chang,Mengji Gong,Jianjun Huang,Yan Pan,Aina He,Jiawei Li,Xinmin Wang
In this work, dense and pinhole-free poly-para-xylylene (PPX) with high thermal stability, high insulating property and high lubricity has been designed as coating layer for Fe-based amorphous powder. Three ultra-thin PPX layers have been successfully deposited on the surface of FeSiBPNbCr amorphous powder via chemical vapor deposition (CVD) polymerization. The micromorphology and chemical structure of the PPX layer on the powder surface, as well as the conversion mechanisms, has been investigated systematically. Several methods have been used to estimate the amount and thickness of PPX layers. The corresponding amorphous powder cores (AMPCs) were also prepared. With the increasing thickness of the PPX layer, the saturation magnetization ( M s ) of the powder decreased slightly but the magnetic flux density ( B s ) of the AMPCs kept at a similar level thanked to the enhanced green density. In addition, the DC bias performance was improved and core loss ( P cv ) was reduced. Compare with other coating materials like epoxy and silicon resin, the PPX layer provided better insulation and higher lubricity for the AMPCs, thus reduced the P cv and improved the DC bias performance. The AMPCs coated by PPX-3 exhibited excellent comprehensive soft magnetic properties, which were promising for high-power and high-frequency applications.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2019
·
IF 13.903
Huihui Liu,Yue Li,Miaomiao Xiang,Hualing Zeng,Xiang Shao
Interfacial charge transfer is critical for the photocatalytic activities of compositional photocatalysts. In this work, we have developed a strategy of growing single-layer MoS2 sheets on the rutile TiO2(110) single-crystal surface using a chemical vapor deposition method. Both on-site and off-site characterizations confirmed the monolayer thickness and single crystallinity of the MoS2 adlayer as well as the atomic flatness of the composite surface. Without the presence of contamination, the charge flow across the interface of MoS2 and TiO2 is greatly enhanced, which hence favors the charge separation under excitations and boots up the catalytic activity of the composite system. Moreover, we found the luminescing property of MoS2 is significantly tailored upon coupling with the TiO2 surface. Our work has established a method for revealing the interface properties of the transition-metal dichalcogenides and oxide semiconductors at the atomic level.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED ENGINEERING MATERIALS
·
2021
·Vol. 23
·期 6
·2001490
·
IF 3.862
Xu Guo,Xiaohong Chen,Ping Liu,Honglei Zhou,Shaoli Fu,Wei Li,Xinkuan Liu,Fengcang Ma,Zhengpeng Wu
CNTs/Cu-Al 2 O 3 composites are successfully prepared by internal oxidation, chemical vapor deposition and spark plasma sintering (SPS) method. The influence of Al content (0.12 and 0.6 wt%) on the morphology of grown carbon nanotubes and the mechanical properties of composites are systematically studied. The results show that under the same growth process, more carbon nanotubes are obtained on the surface of the powders with 0.6 wt% Al content. The CNTs/Cu-Al 2 O 3 composites with 0.12 wt% Al content displays higher mechanical properties, the tensile strength is 280 MPa, and the micro-hardness is 123.3 HV, which is increased by 40.7 and 78.2% in contrast with that of pure copper, respectively. Moreover, the electrical conductivity of CNTs/Cu-Al 2 O 3 (Al content is 0.12 wt%) composites is still at the high level of 83.2% IACS. This work uses chemical vapor deposition to improve the dispersion and interfacial bonding of CNTs in the matrix and increase the properties of the composites, which provides a new idea for the preparation of high strength metal matrix composites.
研究领域:
材料科学
·
力学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Advanced Ceramics
·
2022
·Vol. 11
·期 12
·1932-1943
·
IF 11.534
Fan Shengjie,Sun Tingting,Jiang Meng,Gu Shijia,Wang Lianjun,Yan Haixue,Jiang Wan
As a high-temperature thermoelectric (TE) material, ZnO offers advantages of non-toxicity, chemical stability, and oxidation resistance, and shows considerable promise as a true ready-to-use module under air conditions. However, poor electrical conductivity and high thermal conductivity severely hinder its application. Carbon nanotubes (CNTs) are often used as a reinforcing phase in composites, but it is difficult to achieve uniform dispersion of CNTs due to van der Waals forces. Herein, we developed an effective in-situ growth strategy of homogeneous CNTs on ZnO nanoparticles by exploiting the chemical vapor deposition (CVD) technology, in order to improve their electrical conductivity and mechanical properties, as well as reducing the thermal conductivity. Meanwhile, magnetic nickel (Ni) nanoparticles are introduced as catalysts for promoting the formation of CNTs, which can also enhance the electrical and thermal transportation of ZnO matrices. Notably, the electrical conductivity of ZnO is significantly boosted from 26 to 79 S·cm −1 due to the formation of dense and uniform conductive CNT networks. The lattice thermal conductivity ( κ L ) is obviously declined by the intensification of phonon scattering, resulting from the abundant grain boundaries and interfaces in ZnO-CNT composites. Importantly, the maximum dimensionless figure of merit ( zT ) of 0.04 at 800 K is obtained in 2.0% Ni-CNTs/ZnO, which is three times larger than that of CNTs/ZnO prepared by traditional ultrasonic method. In addition, the mechanical properties of composites including Vickers hardness ( HV ) and fracture toughness ( K IC ) are also reinforced. This work provides a valuable reference for dispersing nano-phases in TE materials to enhance both TE and mechanical properties.
研究领域:
材料科学
·
能源工程
✓ 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）