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41.
Enhanced Performance of a Self‐Powered Organic/Inorganic Photodetector by Pyro‐Phototronic and Piezo‐Phototronic Effects 下载免费PDF全文
Wenbo Peng Xingfu Wang Ruomeng Yu Yejing Dai Haiyang Zou Aurelia C. Wang Yongning He Zhong Lin Wang 《Advanced materials (Deerfield Beach, Fla.)》2017,29(23)
Self‐powered photodetectors (PDs) have long been realized by utilizing photovoltaic effect and their performances can be effectively enhanced by introducing the piezo‐phototronic effect. Recently, a novel pyro‐phototronic effect is invented as an alternative approach for performance enhancement of self‐powered PDs. Here, a self‐powered organic/inorganic PD is demonstrated and the influences of externally applied strain on the pyro‐phototronic and the photovoltaic effects are thoroughly investigated. Under 325 nm 2.30 mW cm‐2 UV illumination and at a ‐0.45% compressive strain, the PD's photocurrent is dramatically enhanced from ≈14.5 to ≈103 nA by combining the pyro‐phototronic and piezo‐phototronic effects together, showing a significant improvement of over 600%. Theoretical simulations have been carried out via the finite element method to propose the underlying working mechanism. Moreover, the pyro‐phototronic effect can be introduced by applying a ‐0.45% compressive strain to greatly enhance the PD's response to 442 nm illumination, including photocurrent, rise time, and fall time. This work provides in‐depth understandings about the pyro‐phototronic and the piezo‐phototronic effects on the performances of self‐powered PD to light sources with different wavelengths and indicates huge potential of these two effects in optoelectronic devices. 相似文献
42.
为实现纳米TiO2颗粒的均匀分散,首先对纳米TiO2进行硅烷改性,再通过溶液共混法制备出不同纳米TiO2添加量的硅烷改性纳米TiO2-Zn-Al/水性环氧复合涂层。研究了纳米TiO2与Zn-Al片层粉在涂层中的综合作用。利用XRD和FTIR分析涂层的物相组成和组织结构,SEM和EDS表征涂层表面的微观形貌和元素组成,采用极化曲线和电化学阻抗谱(EIS)研究涂层的耐腐蚀性能。EDS和FTIR表明,经改性的纳米TiO2均匀分散于涂层中,纳米TiO2与环氧树脂的枝联作用使涂层更加致密。EIS结果显示,由于Zn-Al片层粉与纳米TiO2的枝联和填充作用,使添加纳米TiO2的硅烷改性纳米TiO2-Zn-Al/水性环氧涂层腐蚀行为较未添加纳米TiO2时有所减缓。当纳米TiO2添加量增加到4wt%时,硅烷改性纳米TiO2-Zn-Al/水性环氧涂层的腐蚀电流密度为9.86×10-6 A/cm2,比未添加纳米TiO2的涂层高一个量级。 相似文献
43.
Piezo‐Phototronic Effect on Selective Electron or Hole Transport through Depletion Region of Vis–NIR Broadband Photodiode 下载免费PDF全文
Haiyang Zou Xiaogan Li Wenbo Peng Wenzhuo Wu Ruomeng Yu Changsheng Wu Wenbo Ding Fei Hu Ruiyuan Liu Yunlong Zi Zhong Lin Wang 《Advanced materials (Deerfield Beach, Fla.)》2017,29(29)
Silicon underpins nearly all microelectronics today and will continue to do so for some decades to come. However, for silicon photonics, the indirect band gap of silicon and lack of adjustability severely limit its use in applications such as broadband photodiodes. Here, a high‐performance p‐Si/n‐ZnO broadband photodiode working in a wide wavelength range from visible to near‐infrared light with high sensitivity, fast response, and good stability is reported. The absorption of near‐infrared wavelength light is significantly enhanced due to the nanostructured/textured top surface. The general performance of the broadband photodiodes can be further improved by the piezo‐phototronic effect. The enhancement of responsivity can reach a maximum of 78% to 442 nm illumination, the linearity and saturation limit to 1060 nm light are also significantly increased by applying external strains. The photodiode is illuminated with different wavelength lights to selectively choose the photogenerated charge carriers (either electrons or holes) passing through the depletion region, to investigate the piezo‐phototronic effect on electron or hole transport separately for the first time. This is essential for studying the basic principles in order to develop a full understanding about piezotronics and it also enables the development of the better performance of optoelectronics. 相似文献
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采用冲突驱动回溯、两观察变量法等思想,静态分析和动态更新相结合的排序决策,鼓励冲突,尽早剪除不满足解空间,提高算法速度.根据变量正反文字出现次数的乘积进行初始排序,优先考虑正反文字出现次数较多变量的赋值;采用冲突驱动、动态更新变量顺序、优先考虑发生冲突子句中变量的赋值,尽可能避免当前冲突.实验结果表明:与采用其他决策策略的解决器相比,文中的解决器拥有一定的速度优势. 相似文献
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In order to determine the sensitivity of influencing factors on NOx emission in gas-fired heating and hot water eombi-boilers,the orthogonal method was adopted ... 相似文献
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49.
杨文波 《电脑编程技巧与维护》2008,(17):68-69
网络分发策略对于视频应用的服务质量起着至关重要的作用。本文在分析现有分发策略的基础上,提出了基于启发式视频媒体数据分发策略的思想,并给出了基于C#平台的启发式分发策略的算法描述。 相似文献
50.
Wenbo Zhou Julia Craft Alex Ojemann Luke Bergen Arin Graner Aitana Gonzales Qianbin He Timothy Kopper Marie Smith Michael W. Graner Xiaoli Yu 《International journal of molecular sciences》2022,23(13)
WHO Grade 4 IDH-wild type astrocytoma (GBM) is the deadliest brain tumor with a poor prognosis. Meningioma (MMA) is a more common “benign” central nervous system tumor but with significant recurrence rates. There is an urgent need for brain tumor biomarkers for early diagnosis and effective treatment options. Extracellular vesicles (EVs) are tiny membrane-enclosed vesicles that play essential functions in cell-to-cell communications among tumor cells. We aimed to identify epitopes of brain tumor EVs by phage peptide libraries. EVs from GBM plasma, MMA plasma, or brain tumor cell lines were used to screen phage-displayed random peptide libraries to identify high-affinity peptides. We purified EVs from three GBM plasma pools (23 patients), one MMA pool (10 patients), and four brain tumor cell lines. We identified a total of 21 high-affinity phage peptides (12 unique) specific to brain tumor EVs. The peptides shared high sequence homologies among those selected by the same EVs. Dose–response ELISA demonstrated that phage peptides were specific to brain tumor EVs compared to controls. Peptide affinity purification identified unique brain tumor EV subpopulations. Significantly, GBM EV peptides inhibit brain tumor EV-induced complement-dependent cytotoxicity (necrosis) in neurons. We conclude that phage display technology could identify specific peptides to isolate and characterize tumor EVs. 相似文献