PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
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2021
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IF 3.382
Ali Yazdan,Bingkun Hu,Ce-Wen Nan,Liangliang Li
Boron nitride nanotubes (BNNTs) possess many fascinating properties that make them promising for various applications in microelectronics, biomedicine and coating. In this work, BNNTs were synthesized by a ball milling-annealing method. Boron powder was milled with promoters, lead(II) oxide (PbO) and iron(III) nitrate nonahydrate (Fe(NO 3 ) 3 ⋅9H 2 O), under the N 2 gas environment to prepare a precursor. Then, bamboo-like and cylindrical BNNTs were synthesized by annealing the precursor at 1150 °C under the NH 3 gas environment. The phase of the BNNTs was identified to be hexagonal BN by X-ray diffractometry, Raman spectroscopy and transmission electron microscopy . The effect of the promoter content in the precursor on the synthesis of the BNNTs was investigated. When the mass ratio of B:PbO:Fe(NO 3 ) 3 ⋅9H 2 O was 1:1:1, bamboo-like and cylindrical BNNTs with a diameter of 60–500 nm, uniform composition and polycrystalline microstructure were obtained.
研究领域:
材料科学
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纳米技术
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DOI
高影响因子
Nanoscale
·
2020
·Vol. 12
·期 27
·14739-14750
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IF 6.895
Zi Fu,Gareth R. Williams,Shiwei Niu,Jianrong Wu,Feng Gao,Xuejing Zhang,Yanbo Yang,Yu Li,Li-Min Zhu
In this work, an innovative boron-based multifunctional nanoplatform was developed for synergistic chemotherapy/low temperature photothermal therapy (PTT). This platform is functionalized with a cRGD peptide to allow the targeting of αvβ3 integrin, which is over-expressed in the cells of tumors. The nanoparticles were further loaded with the chemotherapeutic drug doxorubicin (DOX) and a heat shock protein inhibitor (17AAG), and high loading capacities for both DOX (603 mg g−1 B-PEG-cRGD) and 17AAG (417 mg g−1) were obtained. The resultant DOX-17AAG@B-PEG-cRGD system shows both pH-controlled and near-infrared (NIR)-induced DOX and 17AAG release. It also provides significantly enhanced cellular uptake in cancerous cells over healthy cells. The presence of 17AAG allows low-temperature PTT to be combined with chemotherapy with DOX, resulting in highly effective anti-cancer activity. This has been confirmed by both in vitro assays and using an in vivo murine cancer model. It is expected that such a multifunctional nanoplatform can serve as a promising candidate for cancer therapy.
研究领域:
肿瘤学
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纳米医学
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药物递送系统
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2020
·Vol. 55
·期 29
·14345-14357
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IF 3.553
Li Qingsong,Liu Qiangchun,Kong Xiangkai
Abstract Metal-free hybrids possess many advantages when compared with metal-based materials, such as lightweight, low cost, and high stability, which offer great potential for them to be used in wide applications, such as microwave absorption. Bare carbon materials, especially for those derived from wasted biomass, normally cannot simultaneously exhibit strong and broadband absorption performance, due to their specific structures and high electronic conductivity, leading to more incident microwave reflected on surface. Herein, based on wasted grapefruit peels, 2D metal-free hybrids are designed and prepared with pre-exfoliated boron nanoflakes as the modulation. Noncovalent interaction is formed at their heterojunction, which endows them with properties that cannot be supplied by their individual components. As a result, interfacial polarizations and dipole polarizations are generated between the layers, benefiting the dielectric loss and impedance matching behaviors. Microwave absorption measurements demonstrate that the minimum reflection loss can reach − 47.9 dB and the effective absorption frequency band is 4.32 GHz, at 1.5 mm thickness. We hope these represent an addition to the family of sustainable biomass-derived microwave absorbents. Graphic abstract
研究领域:
材料科学
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环境科学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
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IF 16.683
Fahao Ma,Shuhua Wang,Xizhuang Liang,Cong Wang,Fengxia Tong,Zeyan Wang,Peng Wang,Yuanyuan Liu,Ying Dai,Zhaoke Zheng,Baibiao Huang
Electrocatalytic synthesis of hydrogen peroxide (H 2 O 2 ) via the two-electron oxygen reduction reaction (2e − ORR) is an ideal method for the on-site H 2 O 2 production. Herein, Ni 3 B is identified as an active, selective, and stable catalyst for ORR to generate H 2 O 2 , which exhibits a high selectivity of over 90 % and an onset potential of ∼0.7 V versus the reversible hydrogen electrode (RHE). Furthermore, the mass activity of Ni 3 B is about 16.5 A g -1 at 0.52 V (RHE), which is comparable to some noble metal alloys. Our experimental results suggest that the high performance of Ni 3 B originates from the alloying process of Ni and B atoms. The density functional theory calculations reveal that the inner B atoms with high electronegativity decrease the state density of Ni-3d orbital near the Fermi level relative to Ni, which optimizes the binding energy of OOH* and makes Ni 3 B a highly efficient and stable catalyst for the two-electron ORR.
研究领域:
催化
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电化学
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材料科学
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DOI
高影响因子
CATALYSIS LETTERS
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2020
·Vol. 150
·期 9
·2497-2509
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IF 2.482
Yang Qiang,Liu Jiali,Yan Dejian,Liu Jikai,Luo He’an
Abstract Boron-rich alloy boron suboxide (B 6 O) as a novel metal-free photocatalyst was recently explored for photocatalytic CO 2 reduction and water splitting. However, to broaden the potential applications of B 6 O in the field, further improving its activity and understanding its fundamental chemical properties are essential. Herein, transition metal doping (Cr or Co) is designed to engineer the band structure of B 6 O via a solid state reaction. The valence band edge of Cr or Co doped B 6 O is proposed to be more positive than that of pristine B 6 O while the original conduction band of B 6 O is not much influenced by doping, contributing to the better light harvesting ability and lower charge recombination rate of doped B 6 O. The photocatalytic and photoelectrochemical (PEC) performances of doped B 6 O were therefore remarkably enhanced. The apparent quantum yields (AQY) of 20 wt% Cr or Co doped B 6 O are much higher than that of pristine B 6 O. In addition, the 20 wt% Cr doped B 6 O exhibits the best electrical conductivity and photocatalytic performance compared with the Co doped B 6 O and pristine B 6 O. The present work demonstrates a facile and effective strategy to engineer the band structure and reduce the charge migration resistance of B 6 O. Graphic Abstract
研究领域:
材料科学
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光催化
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可再生能源
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DOI
高影响因子
Journal of Materials Chemistry A
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2020
·Vol. 8
·期 15
·7360-7367
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IF 11.301
Weizhao Hong,Shanfu Sun,Yi Kong,Yongyuan Hu,Gang Chen
Developing highly efficient, stable, and inexpensive electrocatalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) is the premise of achieving large-scale water splitting. Here, NixFe1−xB prepared by a facile borothermal reduction in molten salt is a robust bifunctional electrocatalyst for overall water splitting. The NixFe1−xB electrocatalyst achieves a current density of 10 mA cm−2 at overpotentials of 63.5 mV for the HER and 282 mV for the OER in 1 M KOH electrolyte, respectively. Density functional theory (DFT) calculations suggest that the NixFe1−xB possesses a lower absolute value of H* adsorption free energy (|ΔGH*|) than the primitive FeB and NiB, which is beneficial to improve the HER activity. Two identical NixFe1−xB electrodes are combined to form an alkaline electrolyzer, which achieves a current density of 10 mA cm−2 at 1.57 V for overall water splitting. This work provides a strategy to develop highly efficient transition metal boride catalysts for overall water splitting.
研究领域:
材料科学
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理论计算
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电化学
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DOI
高影响因子
SOLID STATE SCIENCES
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2020
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IF 2.434
Jian Lv,Qingran Wang,Peng Chen,Heng Liu,Zhongmin Su,Jianxun Zhao,Wanqiang Liu,Jianhua Hou,Shang Gao
The Co 2 B alloy is synthesized by high temperature solid phase process. 5 wt% Pd is added to the Co 2 B alloy by ball milling at different milling time in order to enhance discharge performance of the raw alloy. The phase structure and surface morphology of these alloys is characterized by XRD and SEM. The discharge capacities of the alloy milled for 10 min and 30 min are higher than that of the raw alloy. However, the discharge capacity of the alloy milled for 1 h is lower than that of the raw alloy. The result of linear polarization and EIS shows that proper milling time and uniform distribution of palladium on the alloy surface can make the alloy electrode have excellent discharge capacity. Ball milling at appropriate time can make the palladium on the alloy surface uniformly distributed and the alloy particles do not aggregate, which increases the charge-transfer reaction rate and discharge capacity. The experimental results prove that the addition of palladium and proper ball milling can effectively improve the electrochemical hydrogen storage capacity of the Co 2 B alloy.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2020
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IF 8.758
Jinqian Hao,Guoan Tai,Jianxin Zhou,Rui Wang,Chuang Hou,Wanlin Guo
Zero-dimensional boron structures have always been the focus of theoretical research owing to their abundant phase structures and special properties. Boron clusters have been reported extensively by combining structure searching theories and photoelectron spectroscopy (PES) experiments; however, crystalline boron quantum dots (BQDs) have rarely been reported. Here, we report the preparation of large-scale and uniform crystalline semiconductor BQDs from the expanded bulk boron powders via a facile and efficient probe ultrasonic approach in the acetonitrile solution. The obtained BQDs have 2.46 nm average lateral size and 2.81 nm thickness. Optical measurements demonstrate that a strong quantum confinement effect occurs in the BQDs, implying the increase of the band gap from 1.80 eV for the corresponding bulk to 2.46 eV for the BQDs. By injecting the BQDs into poly(vinylpyrrolidone) as an active layer, a BQD-based memory device is fabricated that shows a rewriteable nonvolatile memory effect with a low transition voltage of down to 0.5 V and a high on/off switching ratio of 103 as well as a good stability.
研究领域:
材料科学
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半导体物理
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产品关联
DOI
PubMed
高影响因子
CRYSTAL GROWTH & DESIGN
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2020
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IF 4.089
Yunxia Han,Duanwei He,Dejiang Ma,Qiming Wang,Yusheng Zhao,Shanmin Wang,Mingquan Jiang,Xin Li,Jiawei Zhang
We report high-pressure synthesis of single-crystal boron suboxide (B6O), one of the superhard materials, using a reaction route between B and H3BO3 at 3–5.5 GPa and 600–2200 °C. At optimized pressure and temperature conditions of 5.5 GPa and 2100 °C, large B6O single crystals can be obtained with a crystallite size of more than 2 mm. Boric acid (H3BO3) was used as a starting material because it is easily decomposed into B2O3 and H2O at a lower temperature. The B2O3 produced by the decomposition should have a small particle size and thus have high reactivity, and the reaction byproduct H2O provides a good hydrostatic environment for the growth of B6O. Therefore, it is easier to synthesize and grow B6O by using a B-H3BO3 system as reaction raw materials. This work discussed the B6O growth mechanism in detail. In addition, photoluminescence experiments and first-principles calculations show that B6O is a direct band gap semiconductor material with good orange-red emission characteristics (the band gap is 1.83 eV). The results of this study indicate a method to grow large B6O single crystals that have great potential use in industrial applications.
研究领域:
材料科学
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晶体生长
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半导体物理
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产品关联
DOI
高影响因子
ChemSusChem
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2020
·Vol. 13
·期 14
·3662-3670
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IF 7.962
Hefeng Yuan,Shiwei Wei,Bin Tang,Zizai Ma,Jinping Li,Manab Kundu,Xiaoguang Wang
Graphical Flakes make O 2 : Self-supported ultrathin CoNiB nanoflakes are prepared by a simple one-step solid-state boronation. The unique sheet-like structure, bimetallic boride components, and optimal hybrid crystalline nature enable a synergistic promotion for the catalysis of the oxygen evolution reaction with long-term stability. The development of highly active and efficient nonprecious-metal electrocatalysts for the oxygen evolution reaction is important for the design of renewable energy production and storage devices. In this work, highly dense, ultrathin Co–Ni boride nanoflakes supported on a 3 D CoNi skeleton are fabricated in situ by a simple one-step, high-temperature, solid-state boronation process. As a result of the induced high electroactive surface area and low charge transfer resistance, CoNiB-700 exhibits high catalytic activity at an overpotential of 262 ( η 10 ) and 284 mV ( η 20 ) to deliver current densities of 10 and 20 mA cm −2 , respectively, with a Tafel slope of 58 mV dec −1 in an alkaline medium towards the oxygen evolution reaction. DFT calculations show that the Ni-regulated Co–B compound has a lower rate-determining energy barrier for the *OOH intermediate than the mono-Co–B compound, which facilitates the production of more active catalytic sites for an accelerated surface charge-transfer process for the oxygen evolution reaction.
研究领域:
材料科学
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电化学
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产品关联
DOI
PubMed
高影响因子
Materials
·
2019
·Vol. 13
·期 1
·29
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IF 2.972
Jianmeng Jiao,Jafar Safarian,Bettina Grorud,Merete Tangstad
Si-B alloys are proposed as a potential phase change material (PCM) in the novel high temperature thermal energy storage systems. For successfully introducing the new PCM, the selection of proper refractory material in the PCM container is vital. At present, graphite is chosen as a potential refractory material for the PCM container, due to its high temperature stability, low thermal expansion, and high thermal conductivity. The Si-B alloys and the high-temperature interaction with graphite are hence studied. The phase formation in the Si-B alloys and the interaction with graphite at B content of 2–11 mass % and temperatures of 1450–1750 °C were investigated. Carbides were observed at the interface between the solidified alloys and the graphite. A single SiC layer was produced at B content of 2 and 3.25 mass %. Otherwise, SiC and B4C layers were generated at B content higher than 5 mass %. In the Si-B-C system, the phase formation is dependent on the B content. Moreover, the equilibrium B content is calculated to be 3.66 mass % in the molten Si-B alloys at 1450 °C in equilibrium with SiC and B4C, based on the experimental results. In this regard, the eutectic alloy (3.25 mass % B) is recommended to be used as the new PCM in the graphite container, due to that it produces simple phases and also because it is expected not to deplete any B to the B4C layer.Keywords:Si-B alloys;graphite;PCM;carbon solubility;carbides
研究领域:
材料科学
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热能工程
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产品关联
DOI
PubMed
高影响因子
Nano-Micro Letters
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2021
·Vol. 13
·期 1
·1-13
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IF 16.419
Chen Keng,Wang Zeming,Wang Liang,Wu Xiuzhen,Hu Bingjie,Liu Zheng,Wu Minghong
High-efficiency electrochemical hydrogen evolution reaction (HER) offers a promising strategy to address energy and environmental crisis. Platinum is the most effective electrocatalyst for the HER. However, challenging scarcity, valuableness, and poor electrochemical stability still hinder its wide application. Here, we designed an outstanding HER electrocatalyst, highly dispersed rhodium (Rh) nanoparticles with an average diameter of only 3 nm supported on boron (B) nanosheets. The HER catalytic activity is even comparable to that of commercial platinum catalysts, with an overpotential of only 66 mV in 0.5 M H 2 SO 4 and 101 mV in 1 M KOH to reach the current density of 10 mA cm −2 . Meanwhile, the catalyst exhibited impressive electrochemical durability during long-term electrochemical processes in acidic and alkaline media, even the simulated seawater environment. Theoretical calculations unraveled that the structure–activity relationship between B(104) crystal plane and Rh(111) crystal plane is beneficial to the release of hydrogen, and surface O plays a vital role in the catalysis process. Our work may gain insights into the development of supported metal catalysts with robust catalytic performance through precise engineering of the strong metal-supported interaction effect.
研究领域:
材料科学
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催化化学
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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）