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Effect of Calcination Temperature on Photoluminescence Intensity of Sol-Gel prepared Sr2CeO4: Eu3+ Nano Phosphor 煅烧温度对溶胶-凝胶法制备Sr2CeO4: Eu3+纳米荧光粉光致发光强度的影响
Pub Date : 2021-02-22 DOI: 10.30919/ESMM5F429
Paleena Thulimilli
Pure Sr 2 CeO 4 phosphor and Sr 2 CeO 4 doped with europium (0.5, 1.0, 1.5, 2.0, 4.0 mol%) phosphor were synthesized by the sol-gel method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectra were used to characterize the pure Sr 2 CeO 4 and Sr 2 CeO 4 :Eu 3+ nano phosphor. It is a well-known fact that the crystallinity of the material increases with increase in the calcination temperature. Hence to study the effect of calcination temperature on the sol-gel synthesized phosphor (Sr 2 CeO 4 :Eu 3+ (2.0 mol%)), the phosphor was fired at various temperatures 1000, 1100 and 1200 ℃ for 2hrs respectively and it was found that the photoluminescence intensity of Sr 2 CeO 4 :Eu 3+ nano phosphor increases with the increase of calcination temperature. Sr 2 CeO 4 :Eu 3+ nano phosphor has an excellent colour tunability of red light with different concentration of europium and hence it can be a promising candidate for LED lighting Applications.
采用溶胶-凝胶法制备了纯sr2ce4荧光粉和掺铕(0.5、1.0、1.5、2.0、4.0 mol%)荧光粉的sr2ce4。利用x射线衍射(XRD)、扫描电镜(SEM)和光致发光(PL)光谱对纯sr2ceo4和sr2ceo4: eu3 +纳米荧光粉进行了表征。众所周知,材料的结晶度随着煅烧温度的升高而增加。因此,为了研究煅烧温度对溶胶-凝胶合成的荧光粉(sr2ce4: eu3 + (2.0 mol%))的影响,将该荧光粉分别在1000、1100和1200℃的不同温度下煅烧2h,发现sr2ce4: eu3 +纳米荧光粉的光致发光强度随着煅烧温度的升高而增加。sr2 ce4: eu3 +纳米荧光粉对不同铕浓度的红光具有良好的颜色可调性,因此它可以成为LED照明应用的有前途的候选材料。
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引用次数: 5
Study on Copolymer from Cyclic Butylene Terephthalate and Polycaprolactone by In-Situ Polymerization 原位聚合环对苯二甲酸丁二酯与聚己内酯共聚物的研究
Pub Date : 2021-01-01 DOI: 10.30919/esmm5f544
Haijun Zhou, Jinling Wang, Yujie Liu, Zhengyan Chen, Jiaoxia Zhang
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引用次数: 2
Highly Efficient Synthesis of Hexagonal Boron Nitride Nanofibers with High Specific Surface Area 高比表面积六方氮化硼纳米纤维的高效合成
Pub Date : 2021-01-01 DOI: 10.30919/esmm5f561
Hongshou Liu, Zhaoqian Yan, Zhihao Sun, Anran Li, Zihao Guo, Lei Qian
Hexagonal boron nitride nanofibers with high specific surface were successfully prepared through precursor pyrolysis method via boric acid, melamine and polyethylene glycol (PEG) as raw materials. The field emission scanning electron microscopy images showed that hexagonal boron nitride (h-BN) nanofibers were well aligned, and exhibited good fibrous structure. Chemical composition of the synthesized h-BN nanofibers was analyzed by X-ray diffraction, fourier transform infrared spectroscopy and thermogravimetric. Effects of precursor drying method and the PEG contents on morphologies and the specific surface area were investigated and optimized. Results indicated that the diameter of h-BN nanofibers increased with the ratio of boric acid to melamine, and their aspect ratios were greatly improved from 20 to 30 after freeze-drying treatment. Specific surface area of the h-BN nanofibers was increased from 65.25 to 319.07 m 2 /g due to the freeze-drying treatment. Besides, the content of PEG also obviously improved specific surface area. When the PEG content reached 2%, specific surface area of the h-BN nanofibers from the air-dried precursor was increased by 12.4 times to 874.58 m 2 /g. The resulted h-BN nanofibers show promising and potential applications in many fields including catalysis, hydrogen storage and environment.
以硼酸、三聚氰胺和聚乙二醇(PEG)为原料,采用前驱体热解法制备了高比表面六方氮化硼纳米纤维。场发射扫描电镜图像显示,六方氮化硼纳米纤维排列良好,具有良好的纤维结构。利用x射线衍射、傅里叶红外光谱和热重分析了合成的氢氮化硼纳米纤维的化学成分。考察并优化了前驱体干燥方式和聚乙二醇含量对形貌和比表面积的影响。结果表明,随着硼酸与三聚氰胺的比例增加,h-BN纳米纤维的直径增大,经冷冻干燥处理后,其纵横比由20提高到30。经冷冻干燥处理后,h-BN纳米纤维的比表面积由65.25 m2 /g提高到319.07 m2 /g。此外,PEG的加入也明显提高了比表面积。当PEG含量达到2%时,h-BN纳米纤维的比表面积增加了12.4倍,达到874.58 m2 /g。所得氢氮化硼纳米纤维在催化、储氢和环境等领域具有广阔的应用前景。
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引用次数: 7
Friction Control of Chitosan-Ag Hydrogel by Silver Ion 银离子对壳聚糖-银水凝胶的摩擦控制
Pub Date : 2021-01-01 DOI: 10.30919/esmm5f555
Jing Hua, M. Björling, R. Larsson, Y. Shi
The tunable friction behavior of Chitosan (CS)-Ag hydrogel enabled by altering silver ions is evaluated. Friction control could be achieved under boundary lubrication. When adding Ag + into a CS solution, the formed gel provided lower friction. The difference in friction coefficient between the two phases can be reversibly switched by adding Cl - or excessive Ag + ions. It also can be found that the gel phased lubricant has a better anti-wear ability under boundary lubrication conditions. Both solution and gel typed lubricants could achieve superlubricity under elastohydrodynamic lubrication. The switchable and tunable frictional hydrogels can extend the application in the design of smart control equipment. hydrogels to very The gel-network to the facile of metal ions with amino and hydroxy groups in chitosan (CS) chains. These hydrogels were also shown to be responsive to a variety of external stimuli, including pH-value, chemical redox reactions, cations, anions, and neutral species.
研究了银离子改变壳聚糖-银水凝胶的可调摩擦行为。在边界润滑条件下可以实现摩擦控制。当在CS溶液中加入Ag +时,形成的凝胶具有较低的摩擦力。通过加入Cl -或过量的Ag +离子,可以可逆地改变两相之间的摩擦系数差异。同时还发现,凝胶相润滑剂在边界润滑条件下具有较好的抗磨能力。溶液型和凝胶型润滑剂在弹流动力润滑下均能实现超润滑。可切换可调的摩擦水凝胶可以扩展在智能控制设备设计中的应用。壳聚糖(CS)链中含有氨基和羟基基团的金属离子的凝胶网络。这些水凝胶也被证明对各种外部刺激有反应,包括ph值、化学氧化还原反应、阳离子、阴离子和中性物质。
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引用次数: 25
Prospective Futures of Civilian Air Transportation 民用航空运输的未来展望
Pub Date : 2021-01-01 DOI: 10.30919/esmm5f565
D. Bushnell
Civilian air transportation is changing rapidly, is undergoing a renaissance with truly major societal and wide-ranging commercial and industrial level implications. This renaissance is enabled by a plethora of advanced to revolutionary technologies including renewable / “green”/ increasingly inexpensive energy, electric propulsion, nanomaterials and materials processing, printing manufacture, artificial intelligence (AI)/autonomy, an emerging global sensor grid, safety/reliability attainment, miniaturization and resilient navigation and communications. The major component of this renaissance is an ongoing shift to essentially emissionless fly/drive aircraft including personal aircraft, the latter flown from the local street, eventually replacing much of ground transportation and scheduled commercial air traffic. Due to the projected tremendous increase in the number of flying vehicles, autonomous vehicle operation and air traffic control will be essential. The buildout of the personal aircraft markets is projected to be the order of $1T/ year. The benefits of such personal air transportation include major reduced costs for roads and bridges and current auto infrastructures, much shortened travel time, the electric propulsion recharged by renewables resulting in major favorable climate, ecosystem and pollution impacts, and autonomous operation proffers the possibility of saving lives. The applications for small/personal class aircraft include an extensive number of service, business, and governmental uses and far longer, easier, faster commute possibilities. Given projected vehicle improvements and a suitable air traffic control (ATC) system, personal air vehicles could replace much of domestic airline service. They can be used for sport, and should be suitable, being autonomous, for use by the aged and the infirm. The emerging competition for this aero renaissance was apparent in the major-to-historic COVID-19 impacts upon air travel. Tele-travel, immersive, virtual presence as an alternative to air travel has long been under development. The technology, especially bandwidth and virtual reality, has been developed to where this alternative to physical travel is now a serious competition for physical travel of all varieties as proven in the COVID 19 impacts. Tele-travel is one aspect of the rapidly developing tele-everything virtual age that we are entering, including tele-work, tele-commuting, tele-education, tele-medicine, tele-shopping, tele-commerce writ large, telepolitics/entertainment/socialization and with onsite printers, tele-manufacturing. The tele-travel benefits include far less cost, major reductions in climate impacts, far less time, minimal time away from family etc., and far more engagement opportunities, efficiency. For long haul air transport at transonic and supersonic speeds, projections include emissionless electrics with increasing ranges recharged or via green fuels produced by the cost reductions of renewable energy. Then
民用航空运输正在迅速变化,正在经历复兴,具有真正重大的社会和广泛的商业和工业层面的影响。这一复兴得益于大量先进的革命性技术,包括可再生/“绿色”/日益廉价的能源、电力推进、纳米材料和材料加工、印刷制造、人工智能(AI)/自主性、新兴的全球传感器网格、安全/可靠性的实现、小型化和弹性导航和通信。这一复兴的主要组成部分是向基本无排放的飞行/驱动飞机的持续转变,包括个人飞机,后者从当地街道起飞,最终取代大部分地面运输和定期商业空中交通。由于预计飞行车辆数量将大幅增加,自动驾驶车辆操作和空中交通管制将至关重要。个人飞机市场的建设预计将达到每年1万亿美元的规模。这种个人航空运输的好处包括大大降低了道路、桥梁和现有汽车基础设施的成本,大大缩短了旅行时间,由可再生能源充电的电力推进系统对气候、生态系统和污染产生了重大有利影响,自主操作为拯救生命提供了可能。小型/个人级飞机的应用包括广泛的服务、商业和政府用途,以及更长、更容易、更快的通勤可能性。考虑到预计的交通工具改进和合适的空中交通管制系统,个人飞行器可能会取代大部分国内航空服务。它们可以用于体育运动,并且应该是适合的,是自主的,供老年人和体弱者使用。从2019冠状病毒病对航空旅行的重大甚至历史性影响来看,这场航空复兴的竞争日益激烈。远程旅行,身临其境,虚拟存在作为航空旅行的替代方案已经开发了很长时间。这项技术,特别是带宽和虚拟现实,已经发展到这种替代物理旅行的技术,现在已经成为各种物理旅行的严重竞争,这在COVID - 19的影响中得到了证明。远程旅行是我们正在进入的飞速发展的远程一切虚拟时代的一个方面,包括远程工作、远程通勤、远程教育、远程医疗、远程购物、远程电子商务、远程政治/娱乐/社交以及现场打印机、远程制造。远程旅行的好处包括成本低得多,大大减少了对气候的影响,时间短得多,远离家人的时间少得多等,以及更多的参与机会和效率。对于跨音速和超音速的长途航空运输,预测包括无排放的电动汽车,充电里程增加,或通过可再生能源成本降低产生的绿色燃料。然后是生物燃料,盐生植物是一种生长在使用含盐海水的荒地上的盐植物,具有巨大的潜力。此外,通过减少阻力,可以使空气动力性能加倍,从而可以在给定电池能量密度的情况下增加可实现的范围。此外,还有先进的纳米复合材料和纳米级金属打印,具有极好的微结构,可以提供干重减轻和额外的范围增加。可再生能源目前与化石碳发电的成本持平或更低,其成本仍在继续下降。目前,可再生能源约占新发电能力的95%,目前约占全球电力的28%,预计在二三十年后,可再生能源的发电量将达到80%。可再生能源和能源存储的成本在过去三年中下降了约70%,这似乎为未来的电动或绿色燃料飞机提供了最小的排放。有两种截然不同的方法被用于改进材料,更强,更轻的重量,更耐用等。第一种是纳米管复合材料。第二种是由多年来的观察得出的,即由于各种材料加工方法产生的位错和晶界问题,金属的性能下降了20倍。改进的方法是在纳米尺度上进行打印,通过投影工程科学,生产出大大改善的微观结构和性能,提高了5倍
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引用次数: 10
The Effect of Zirconium and Yttrium Oxide on the Microstructure and Mechanical Properties of Ti-Si-Zr Based Composites 氧化锆和氧化钇对Ti-Si-Zr基复合材料组织和力学性能的影响
Pub Date : 2021-01-01 DOI: 10.30919/esmm5f551
Vitus Mwinteribo Tabie, Xiao-jing Xu, Liangliang Wei, Xiangzhong Shi
Ti-4Si-xZr-yY2O3/5TiO2 matrix composites, containing various weight percentages (0 and 1.3) of zirconium and (0 and 0.3) yttrium oxide, were synthesized via ball milling and powder metallurgical route. Mechanical alloying of the powders was confirmed after ball milling using x-ray diffraction (XRD) and scanning electron microscope (SEM). The ball-milled powders were cold compacted at a pressure of 550 MPa. Sintering was done first at 600 °C for 2h, followed by 800 °C for 2h, then 1000 °C for 2h and finally at 1250 °C for 3h, all in a controlled vacuum environment. The effect of the addition in weight percentages of Zr and Y2O3 on the microstructure, porosity, hardness, elastic modulus, and fracture toughness of the sintered composites, were studied. The results show improvements in the microhardness by 2.2 times, elastic modulus by 34.3%, porosity by 50 %, and fracture toughness by 57%, when Zr and Y2O3 content was 1.3 wt% and 0.3 wt%, respectively. The improvements in the microstructure and mechanical properties can be attributed to the formation of more stable; Ti5Si3 and Ti5Si4 phases and the solid solutions of Ti2Zr, Zr3Si2, and Ti2Zr3Si3 compounds.
采用球磨法和粉末冶金法合成了含有不同重量百分比锆(0和1.3)和氧化钇(0和0.3)的Ti-4Si-xZr-yY2O3/5TiO2基复合材料。采用x射线衍射(XRD)和扫描电镜(SEM)对球磨后粉末的机械合金化进行了验证。在550 MPa的压力下对球磨粉末进行冷压。首先在600°C下烧结2h,然后在800°C下烧结2h,然后在1000°C下烧结2h,最后在1250°C下烧结3h,所有这些都在受控的真空环境中进行。研究了Zr和Y2O3质量分数对烧结复合材料显微组织、孔隙率、硬度、弹性模量和断裂韧性的影响。结果表明,当Zr和Y2O3含量分别为1.3 wt%和0.3 wt%时,合金的显微硬度提高2.2倍,弹性模量提高34.3%,孔隙率提高50%,断裂韧性提高57%。显微组织和力学性能的改善可归因于形成更加稳定;Ti5Si3和Ti5Si4相以及Ti2Zr、Zr3Si2和Ti2Zr3Si3化合物的固溶体。
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引用次数: 1
Reduced Graphene Oxide Based Electrochemical Nonenzymatic Human Serum Glucose Sensor 基于还原氧化石墨烯的电化学非酶人血清葡萄糖传感器
Pub Date : 2021-01-01 DOI: 10.30919/esmm5f486
Medha Gijare, Sharmila Chaudhari, S. Ekar, A. Garje
Present work proposes green synthesis of reduced graphene oxide using lemon peel extract(vitamin-c) and its application as an electrochemical nonenzymatic human serum glucose sensor. Improved modified Hummer’s method was preferred for the preparation of graphene oxide. X-ray diffraction (XRD), Ultraviolet-visible absorption spectroscopy (UV-Vis) and X-ray photon spectroscopy (XPS) analysis revealed the successful reduction of Graphene oxide (GO) using lemon peel extract. Field emission scanning electron microscopy (FESEM), Fourier transform infra-red spectroscopy (FTIR) and Raman spectroscopy supports the formation of reduced graphene oxide (rGO) nanosheets. The proposed glucose sensor exhibits high sensitivity of 1402 μA·cm −2 mM −1 (S/N=3) along with correlation coefficient of 0.9887 and low detection limit of 0.011 μM. The sensor has detected glucose with RSD of 1.99% in human blood serum. The measured values are well agreed with the values obtained using professional glucose sensor used in hospitals.
目前,研究人员提出利用柠檬皮提取物(维生素c)绿色合成还原性氧化石墨烯,并将其应用于电化学非酶人血清葡萄糖传感器。改进后的Hummer方法是制备氧化石墨烯的首选方法。x射线衍射(XRD)、紫外可见吸收光谱(UV-Vis)和x射线光子光谱(XPS)分析表明,柠檬皮提取物成功还原了氧化石墨烯(GO)。场发射扫描电子显微镜(FESEM)、傅里叶变换红外光谱(FTIR)和拉曼光谱支持还原氧化石墨烯(rGO)纳米片的形成。该传感器灵敏度为1402 μA·cm−2 mM−1 (S/N=3),相关系数为0.9887,检出限为0.011 μM。该传感器对人血清中葡萄糖的检测RSD为1.99%。测量值与医院使用的专业血糖传感器测量值吻合良好。
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引用次数: 40
Wavelet Power and Shannon Entropy Applied to Acoustic Emission Signals for Corrosion Detection and Evaluation of Reinforced Concrete 应用小波功率和香农熵对声发射信号进行钢筋混凝土腐蚀检测与评价
Pub Date : 2021-01-01 DOI: 10.30919/esmm5f554
Jinrui Zhang, Ziye Kang, D. Hou, Biqin Dong, Hongyan Ma
Acoustic emission (AE) signals detected from corrosion test on a steel reinforced concrete beam subjected to the coupling effects of corrosive wet-dry cycles and static load are analyzed by power spectral density, wavelet transform, and Shannon entropy. The degradation process of the corroded reinforced concrete beam can be divided into four stages on the basis of the accumulated event number (AEN). Due to the difference of material properties, steel reinforcement and concrete matrix have distinguished AE features. The time-frequency characteristics of AE signals can reflect the microstructural degradation mechanism of steel corrosion and concrete cracking. The corrosion evaluation entails investigating the evolution of the wavelet power mathematically by Shannon entropy. The frequency-entropy clearly exhibits the relative power distribution of AE signal in a certain frequency region. With the accumulation of steel corrosion and concrete deterioration, the increment of the overall entropy integration is considerably apparent. The variation of frequency-entropy curve reveals the corrosion revolution of the reinforced concrete members under static load, which is represented by a transforming from corrosion-induced micro cracking to load-induced localized cracking.
采用功率谱密度、小波变换和香农熵对受腐蚀干湿循环和静载荷耦合作用的钢筋混凝土梁腐蚀试验声发射信号进行分析。基于累积事件数(AEN),钢筋混凝土腐蚀梁的退化过程可分为4个阶段。由于材料性能的不同,钢筋和混凝土基体具有不同的声发射特征。声发射信号的时频特性可以反映钢腐蚀和混凝土开裂的微观结构退化机理。腐蚀评估需要用香农熵来研究小波幂的数学演化。频率熵清晰地反映了声发射信号在某一频率区域内的相对功率分布。随着钢筋腐蚀和混凝土劣化的累积,总熵积分的增量相当明显。频率-熵曲线的变化揭示了静荷载作用下钢筋混凝土构件的腐蚀演变过程,即由腐蚀诱发的微裂缝向荷载诱发的局部裂缝转变。
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引用次数: 8
Zinc Oxide/Graphene Oxide Nanocomposites: Synthesis, Characterization and Their Optical Properties 氧化锌/氧化石墨烯纳米复合材料:合成、表征及其光学性能
Pub Date : 2021-01-01 DOI: 10.30919/esmm5f516
Avinash R. Kachere, Prashant M. Kakade, Archana R. Kanwade, Priyanka Dani, Nandkumar T. Mandlik, Sachin R. Rondiya, N. Dzade, S. Jadkar, S. Bhosale
In this research, the synthesis of high-quality zinc oxide (ZnO) and graphene oxide (GO) nanocomposite (ZnO/GO nanocomposite) was carried out using the simple and efficient hydrothermal method. The ZnO and GO were separately synthesised by using the precipitation and modified Hummer’s method, respectively. Likewise, the effects of different concentrations of GO on the structural and optical properties of ZnO nanoparticles were investigated. All the desired samples were structurally characterized by X-ray diffraction (XRD) and Raman spectroscopy. Those structural characterised techniques indicate the presence of characteristic peaks of ZnO, GO and related elements in the ZnO/GO nanocomposite. Scanning electron microscopy showed that some portions of the spherical shaped ZnO nanoparticles reacted with GO nanosheets to form ZnO nanorods with the formation of reduced graphene oxide (r-GO). UV-Visible and photoluminescence spectroscopy revealed that the optical properties of the ZnO/GO nanocomposite were affected by the GO concentration. The narrowing of optical band gap in the ZnO/GO nanocomposite was observed to pure ZnO sample. The improved optical properties displayed by the ZnO/GO nanocomposites makes them suitable for applications like UV-Vis optoelectronics devices and photocatalytic applications.
本研究采用简单高效的水热法制备了高品质氧化锌(ZnO)和氧化石墨烯(GO)纳米复合材料(ZnO/GO纳米复合材料)。采用沉淀法和改进Hummer法分别合成了氧化锌和氧化石墨烯。同样,研究了不同浓度氧化石墨烯对ZnO纳米粒子结构和光学性质的影响。用x射线衍射(XRD)和拉曼光谱对样品进行了结构表征。这些结构表征技术表明ZnO/GO纳米复合材料中存在ZnO、GO和相关元素的特征峰。扫描电镜显示,部分球形氧化锌纳米颗粒与氧化石墨烯纳米片反应形成氧化锌纳米棒,并形成还原氧化石墨烯(r-GO)。紫外可见光谱和光致发光光谱结果表明,氧化石墨烯浓度对ZnO/GO纳米复合材料的光学性能有影响。在纯ZnO样品中观察到ZnO/GO纳米复合材料的光学带隙缩小。ZnO/GO纳米复合材料所表现出的光学性能的改善,使其适用于UV-Vis光电子器件和光催化应用。
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引用次数: 15
Structural, Optoelectronic, and Photoelectrochemical Investigation of CdSe NC's Prepared by Hot Injection Method 热注射法制备CdSe NC的结构、光电及光电化学研究
Pub Date : 2020-12-12 DOI: 10.30919/esmm5f1040
S. Barma, Sachin R. Rondiya, Y. Jadhav, Sagar B. Jathar, Ganesh K. Rahane, Avinash V. Rokade, Russell W. Cross, Mamta P Nasane, Vijaya Jadkar, N. Dzade, S. Jadkar
In this study, we report the synthesis and characterization of CdSe nanocrystals (NC's) by facile hot injection (HI) method. The formation of CdSe NC's was confirmed by X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The optical properties were analyzed by UV-visible and photoluminescence (PL) spectroscopy shows an excitonic peak at 617 nm in PL spectra corresponds to the band gap of  2 eV favourable for optoelectronic device applications. The Photoelectrochemical (PEC) performance of CdSe thin film prepared by spin coating method demonstrates a rise of photocurrent density (Jsc = 0.081 μAcm) after illumination. The Mott-Schottky (MS) and electrochemical impedance spectroscopy (EIS) measurements were further carried out to understand intrinsic properties namely the type of conductivity, flat band potential, charge carrier density (ND), charge transfer resistance, and recombination lifetime. The n-type conductivity, the charge carrier density of ND = 1.292 x 10 cm, and recombination lifetime of 32.4 μs suggest the ideal behaviour of CdSe NC's for device quality photoelectrodes.
在这项研究中,我们报告了用易热注射(HI)方法合成和表征CdSe纳米晶体(NC's)。通过x射线衍射(XRD)、拉曼光谱(Raman spectroscopy)和x射线光电子能谱(XPS)证实了CdSe NC的形成。通过紫外可见光谱学和光致发光(PL)光谱分析发现,在617 nm处有一个激子峰,对应于2 eV的带隙,有利于光电子器件的应用。自旋镀膜法制备的CdSe薄膜的光电化学(PEC)性能表明,光照后光电流密度上升(Jsc = 0.081 μAcm)。进一步进行了Mott-Schottky (MS)和电化学阻抗谱(EIS)测量,以了解其固有特性,即电导率类型、平带电位、电荷载流子密度(ND)、电荷转移电阻和复合寿命。n型电导率,ND载流子密度为1.292 x 10 cm,复合寿命为32.4 μs,表明CdSe NC具有器件级光电极的理想性能。
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引用次数: 11
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