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31.
With the increasing demand for low cost, long lifetime, high energy density storage systems, an extensive amount of effort has recently been focused on the development of sodium‐ion batteries (SIBs), and a variety of cathode materials have been discovered. However, looking for the most suitable anode material for practical application is a major challenge for SIBs. Herein, a high capacity sulfur‐doped black phosphorus‐TiO2 (TiO2‐BP‐S) anode material for SIBs is first synthesized by a feasible and large‐scale high‐energy ball‐milling approach, and its stability in air exposure is investigated through X‐ray photoelectron spectroscopy. The morphology of TiO2‐BP‐S is characterized using transmission electron microscopy, indicating that the TiO2 nanoparticles produce P? Ti bonds with BP. The TiO2‐BP‐S composite with P? S and P? Ti bonds exhibits excellent stability in air and the superior electrochemical performance. For example, the discharge specific capacity is up to 490 mA h g?1 after 100 cycles at 50 mA g?1, and it remains at 290 mA h g?1 after 600 cycles at 500 mA g?1. Meanwhile, the scientific insight that the formation of stable P? S and P? Ti bonds can provide a guide for the practical large‐scale application of SIBs in other titanium base and black phosphorus materials is looked forward.  相似文献   
32.
p型单晶硅太阳电池在EL检测过程中,部分电池片出现黑斑现象.结合X射线能谱分析(EDS),对黑斑片与正常片进行对比分析,发现黑斑片电池与正常电池片大部分表面的成分相同,排除了镀膜及丝网印刷过程中产生黑斑的可能.利用X射线荧光光谱分析(XRF)测试了同一电池片的黑斑区域与正常区域,发现黑斑处Ca含量较大,并出现Sr、Ge和S等杂质元素.将6个档位的电池片制备成2 cm×2 cm的电池样片,利用光生诱导电流测量了每个电池的外量子效率(EQE).在460~1 000 nm波长范围内,同一电池片黑斑处与正常处的EQE相差较大,说明黑斑的出现与原生硅片缺陷无关,应归结于电池片生产过程中引入的杂质缺陷.给出了杂质引入的原因以及解决途径,从而显著减小了黑斑片产生的几率.  相似文献   
33.
主要阐述了利用微电子机械加工技术制作一种新型的微电极集成生物传感器 ,并利用电化学方法在微电极表面固定超微粒的纳米材料 ,检验纳米材料对生物传感器稳定性、灵敏度、响应时间等影响。这种具有纳米尺度效应的生物传感器将在生物医学领域有着广阔的应用前景。  相似文献   
34.
崔庆忠  焦清介  任慧 《含能材料》2005,13(6):389-392
以酚酞和氢氧化钾的反应物替代木炭,通过调整硝酸钾、硫磺、酚酞及氢氧化钾的混合比例对无木炭黑火药配方进行优化设计,对比研究了普通黑火药与无木炭黑火药在机械感度、静电火花感度、热分解过程及输出特性等方面的差异。研究认为:无木炭黑火药的机械感度、静电火花感度、爆发点比普通黑火药低,而且安全性好,做功能力强,输出稳定性高。  相似文献   
35.
Poly(acrylonitrile-co-butadiene-co-styrene) (ABS), an engineering plastic, was combined with carbon black (CB) to increase its conductivity. The ABS/CB composites were prepared using two different methods: dissolution of ABS in Butan-2-one and manual mixing of the constituent materials. These fabrication methods led to different microstructures, which led to vastly different electrical properties. The microstructures were acquired using scanning electron microscopy (SEM) and optical microscopy, while the electrical conductivity was obtained using impedance spectroscopy. The percolation threshold of the composites fabricated using the manual mixing method was found to be much lower (0.0054 vol.% CB) than that of the composites fabricated using the dissolution method (2.7 vol.% CB).  相似文献   
36.
势垒层对黑硅光电探测器性能影响的研究   总被引:1,自引:3,他引:1  
讨论势垒层Si3N4的引入对黑硅光电探测器光电性能的影响。探测器采用金属一半导体一金属(MSM)器件结构在黑硅层和电极间增加一层势垒层以提高肖特基势垒,从而减低器件的暗电流。实验表明,在相同的光照情况下,有势垒层的探测器暗电流比无势垒层的探测器暗电流至少低1个数量级,且势垒层厚度增加30nm其暗电流降低约1个数量级,而...  相似文献   
37.
To achieve an accurate diagnosis and efficient tumor treatment, developing a facile and powerful strategy to build multifunctional nanotheranostics is highly desirable. Benefiting from the distinct characteristics of black phosphorus quantum dots (BPQDs), herein, a versatile nanoprobe (H-MnO2/DOX/BPQDs) is constructed for dual-modality cancer imaging and synergistic chemo-phototherapy. The hollow mesoporous MnO2 (H-MnO2) nanoparticles are sequentially decorated with a cationic polymer poly (allylamine hydrochloride) (PAH) and an anionic polymer poly (acrylic acid) (PAA). The obtained H-MnO2-PAH-PAA is covalently grafted with BPQDs-PEG-NH2 via a carbodiimide cross-linking reaction and then loaded with anti-cancer drug DOX to form final nanoprobe H-MnO2/DOX/BPQDs. Under the tumor microenvironment, H-MnO2/DOX/BPQDs is degraded to release encapsulated functional molecules DOX and BPQDs. DOX acts as the chemotherapy and fluorescence imaging agent, and BPQDs endows the nanoprobe with photodynamic therapy (PDT) and photothermal therapy (PTT) abilities under dual laser irradiation of 630 and 808 nm. H-MnO2 offers contrasts for magnetic resonance imaging (MRI) and facilitates conversion of endogenous H2O2 to oxygen, thereby relieving tumor hypoxia and enhancing PDT efficacy. All in vitro and in vivo results demonstrate that the designed nanoprobe displays dual-modality MRI/FL imaging and synergistic chemotherapy/PDT/PTT, which ultimately enhances the accuracy of cancer diagnosis and therapeutic performance.  相似文献   
38.
Surface reconstruction (SRC) is a common phenomenon and a promotion manner for Ni/Co-based precatalysts during the water splitting process. However, the catalytic surface reconstruction will in turn complicate the streamlined prediction and modeling on the catalytic activity. Hence, the rational design of anti-SRC catalysts is highly desirable, but challengeable. In this article, a series of affordable bimetal-incorporated black phosphorene (BP) catalysts are constructed by an in situ electro-exfoliation/insertion method for anti-SRC water electrolysis. It is found that the bimetals (e.g., NiFe, NiPd) are of cationic and covalent incorporation with electron-deficient state in few-layer BP. The optimized bimetal-BP structures present excellent and stable catalytic performances with low overpotentials in hydrogen evolution (HER, 53 mV, NiPd-BP) and oxygen evolution (OER, 268 mV, NiFe-BP) reactions at 10 mA cm−2 in 1 m KOH. The anti-SRC behaviors are elucidated by in situ Raman studies during HER/OER, probably due to the balanced electron transfer pathway on Ni sites. This research opens interesting possibilities for designing the anti-SRC catalysts for efficient hydrogen production and authentic structure-activity understandings.  相似文献   
39.
This research illustrates a precise linear and elliptical antenna array design for synthesising the optimal far-field radiation pattern in the fifth-generation (5G) communication spectrum using a meta-heuristic optimisation technique known as black widow optimisation (BWO). 5G communication is an emerging technology with revolutionary changes in the wireless communication system with ultra-high data rate, enhanced capacity, low latency and good quality of service. An accurate antenna array design for an ideal far-field radiation pattern synthesis with a suppressed side lobe level (SLL) value and half power beam width (HPBW) is the most crucial aspect of 5G communications. A suppressed SLL is necessary to reduce interference in the entire side lobe region, whereas a low HPBW is required for long-distance communication. Here, the BWO is employed to find the optimal feeding current to each array element to lower the SLL and the HPBW value. The BWO algorithm sustains impeccable equity between the exploration and exploitation stages to impact different potential regions of the search space and generate new solutions to attain the global optima by evading the trap of local optima. The design examples of the linear antenna array (LAA) and elliptical antenna array (EAA) are illustrated in this article by applying the optimal feeding currents to each array element. Compared to the uniform antenna array and methodologies described in the recently published literature, the results obtained utilising the BWO algorithm for designing the LAAs and EAAs demonstrate a substantial development in the reduction of SLL and HPBW.  相似文献   
40.
选用天然黑色海水珍珠、活性超级黑染色黑珍珠、辐照处理黑珍珠和硝酸盐染色黑珍珠,对其进行拉曼光谱测试、紫外可见吸收光谱测试的研究。两项测试表明:拉曼光谱中天然黑色海水珍珠、硝酸银染色和辐照黑珍珠均出现1080cm-1和699cm-1文石的特征拉曼峰,辐照黑珍珠荧光背景较强,染料染色黑珍珠的出峰位置与所使用染料的类型有关;紫外可见吸收光谱中,天然黑色海珍珠出现284nm和357nm两个吸收峰,染料活性超级黑染色珍珠出现380nm吸收峰,应为357nm吸收峰发生红移所致,银盐染色黑珍珠和辐照处理黑珍珠紫外区吸收峰消失。根据拉曼和紫外可见光谱特征,可以快速、无损地鉴定天然黑色珍珠和各种着色黑珍珠。  相似文献   
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