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151.
The Light‐Induced Field‐Effect Solar Cell Concept – Perovskite Nanoparticle Coating Introduces Polarization Enhancing Silicon Cell Efficiency
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Yusheng Wang Zhouhui Xia Lijia Liu Weidong Xu Zhongcheng Yuan Yupeng Zhang Henning Sirringhaus Yeshayahu Lifshitz Shui‐Tong Lee Qiaoliang Bao Baoquan Sun 《Advanced materials (Deerfield Beach, Fla.)》2017,29(18)
Solar cell generates electrical energy from light one via pulling excited carrier away under built‐in asymmetry. Doped semiconductor with antireflection layer is general strategy to achieve this including crystalline silicon (c‐Si) solar cell. However, loss of extra energy beyond band gap and light reflection in particular wavelength range is known to hinder the efficiency of c‐Si cell. Here, it is found that part of short wavelength sunlight can be converted into polarization electrical field, which strengthens asymmetry in organic‐c‐Si heterojunction solar cell through molecule alignment process. The light harvested by organometal trihalide perovskite nanoparticles (NPs) induces molecular alignment on a conducting polymer, which generates positive electrical surface field. Furthermore, a “field‐effect solar cell” is successfully developed and implemented by combining perovskite NPs with organic/c‐Si heterojunction associating with light‐induced molecule alignment, which achieves an efficiency of 14.3%. In comparison, the device with the analogous structure without perovskite NPs only exhibits an efficiency of 12.7%. This finding provides a novel concept to design solar cell by sacrificing part of sunlight to provide “extra” asymmetrical field continuously as to drive photogenerated carrier toward respective contacts under direct sunlight. Moreover, it also points out a method to combine promising perovskite material with c‐Si solar cell. 相似文献
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153.
Junzhan Wang Satyaprasad P. Senanayak Jie Liu Yuanyuan Hu Yanjun Shi Zelun Li Caixin Zhang Bingyan Yang Longfeng Jiang Dawei Di Anton V. Ievlev Olga S. Ovchinnikova Tao Ding Huixiong Deng Liming Tang Yunlong Guo Jianpu Wang Kai Xiao Deepak Venkateshvaran Lang Jiang Daoben Zhu Henning Sirringhaus 《Advanced materials (Deerfield Beach, Fla.)》2019,31(35)
Optoelectronic devices based on metal halide perovskites, including solar cells and light‐emitting diodes, have attracted tremendous research attention globally in the last decade. Due to their potential to achieve high carrier mobilities, organic–inorganic hybrid perovskite materials can enable high‐performance, solution‐processed field‐effect transistors (FETs) for next‐generation, low‐cost, flexible electronic circuits and displays. However, the performance of perovskite FETs is hampered predominantly by device instabilities, whose origin remains poorly understood. Here, perovskite single‐crystal FETs based on methylammonium lead bromide are studied and device instabilities due to electrochemical reactions at the interface between the perovskite and gold source–drain top contacts are investigated. Despite forming the contacts by a gentle, soft lamination method, evidence is found that even at such “ideal” interfaces, a defective, intermixed layer is formed at the interface upon biasing of the device. Using a bottom‐contact, bottom‐gate architecture, it is shown that it is possible to minimize such a reaction through a chemical modification of the electrodes, and this enables fabrication of perovskite single‐crystal FETs with high mobility of up to ≈15 cm2 V?1 s?1 at 80 K. This work addresses one of the key challenges toward the realization of high‐performance solution‐processed perovskite FETs. 相似文献
154.
The precedence effect in two-click stimuli was investigated by measuring observers' sensitivity to interaural time delays (ITDs) as a function of interclick interval (ICI). A two-interval two-alternative forced-choice discrimination paradigm was used in two stimulus configurations: type I, a dichotic click with a given ITD preceded a diotic click; and type II, a dichotic click followed a diotic click. Threshold ITDs were measured in each configuration for a finely sampled distribution of ICIs that ranged from 0.1 to 25.6 ms. Performance was characterized by the "threshold elevation factor" (TEF) which normalized each of the observers' type I and type II ITD thresholds relative to their ITD threshold for a single dichotic click. The finer sampling of ICIs revealed two novel results: First, for two observers, sensitivity to ITD in the later arriving ITD (type II) oscillated in a consistent and systematic way with changes in ICI. Second, when the ICI reached 12.8 ms, ITD thresholds in the type I and type II configurations were equal but nearly a factor of 2 greater than for a single dichotic click. Some aspects of the data are consistent with the phenomenon of binaural adaptation. 相似文献
155.
Henning Bordihn Victor Mitrana Maria C. Negru Andrei Păun Mihaela Păun 《Natural computing》2018,17(4):799-809
In this paper, we consider the computational power of a new variant of networks of splicing processors in which each processor as well as the data navigating throughout the network are now considered to be polarized. While the polarization of every processor is predefined (negative, neutral, positive), the polarization of data is dynamically computed by means of a valuation mapping. Consequently, the protocol of communication is naturally defined by means of this polarization. We show that networks of polarized splicing processors (NPSP) of size 2 are computationally complete, which immediately settles the question of designing computationally complete NPSPs of minimal size. With two more nodes we can simulate every nondeterministic Turing machine without increasing the time complexity. Particularly, we prove that NPSP of size 4 can accept all languages in NP in polynomial time. Furthermore, another computational model that is universal, namely the 2-tag system, can be simulated by NPSP of size 3 preserving the time complexity. All these results can be obtained with NPSPs with valuations in the set \(\{-1,0,1\}\) as well. We finally show that Turing machines can simulate a variant of NPSPs and discuss the time complexity of this simulation. 相似文献
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157.
Mingfei Xiao Aditya Sadhanala Mojtaba Abdi-Jalebi Tudor H. Thomas Xinglong Ren Tao Zhang Hu Chen Remington L. Carey Qijing Wang Satyaprasad P. Senanayak Cameron Jellett Ada Onwubiko Maximilian Moser Hailiang Liao Wan Yue Iain McCulloch Mark Nikolka Henning Sirringhaus 《Advanced functional materials》2021,31(7):2007359
The measurement of the mechanical properties of conjugated polymers can reveal highly relevant information linking optoelectronic properties to underlying microstructures and the knowledge of the glass transition temperature (Tg) is paramount for informing the choice of processing conditions and for interpreting the thermal stability of devices. In this work, we use dynamical mechanical analysis to determine the Tg of a range of state-of-the-art conjugated polymers with different degrees of crystallinity that are widely studied for applications in organic field-effect transistors. We compare our measured values for Tg to the theoretical value predicted by a recent work based on the concept of effective mobility ζ. The comparison shows that for conjugated polymers with a modest length of the monomer units, the Tg values agree well with theoretically predictions. However, for the near-amorphous, indacenodithiophene–benzothiadiazole family of polymers with more extended backbone units, values for Tg appear to be significantly higher, predicted by theory. However, values for Tg are correlated with the sub-bandgap optical absorption suggesting the possible role of the interchain short contacts within materials’ amorphous domains. 相似文献
158.
Stennicke Henning R.; Mortensen Uffe H.; Christensen Ulla; Remington S.James; Breddam Klaus 《Protein engineering, design & selection : PEDS》1994,7(7):911-916
Carboxypeptidase Y is a serine carboxypeptidase isolated fromSaccharomyces cerevisiae with a preference for Cterminal hydrophobicamino acid residues. In order to alter the inherent substratespecificity of CPD-Y into one for basic amino acid residuesin P'1, we have introduced Asp and/or Glu residues at a numberof selected positions within the Si binding site. Hie effectsof these substitutions on the substrate specificity, pH dependenceand protein stability have been evaluated. The results presentedhere demonstrate that it is possible to obtain significant changesin the substrate preference by introducing charged amino acidsinto the framework provided by an enzyme with a quite differentspecificity. The introduced acidic amino acid residues providea marked pH dependence of the (kcat/Km)FA-A-R-OH/(kcatm)FA-A-R-OHratio. The change in stability upon introduction of Asp/Gluresidues can be correlated to the difference in the mean buriedsurfac surface area between the substituted and the substitutingamino acid. Thus, the effects of acidic amino acid residueson the protein stability depend upon whether the introducedamino acid protrudes from the solvent accessible surface asdefined by the surrounding residues in the wild type enzymeor is submerged below. 相似文献
159.
Anna Wonaschuetz Theresa Haller Eva Sommer Lorenz Witek Hinrich Grothe Regina Hitzenberger 《Aerosol science and technology》2019,53(1):21-28
Steam collection devices collecting aerosol particles into liquid samples are frequently used to analyze water-soluble particulate material. The fate of water-insoluble components is often neglected. In this work, we show that fresh soot particles can be suspended into pure water using a steam collection device, the particle-into-liquid sampler (PILS, Weber et?al. 2001). The overall collection efficiency of freshly generated soot particles was found to be on the order of 20%. This shows that, depending on the analytic technique employed, the presence of insoluble, and/or hydrophobic particles in liquid samples from steam collection cannot be neglected.
Copyright © 2018 The Author(s). Published with license by Taylor & Francis Group, LLC 相似文献
160.
The expected amount of plant nitrogen (N) at harvest which originates from soil N supply is of high relevance for N fertilization planning. Due to mineralization–immobilisation turnover processes, soil N supply is influenced by N fertilization which complicates its assessment. The soil N supply consists of two components: the soil mineral N measured at early spring and the ‘effective’ N mineralization (Mineff) under winter wheat (Triticum aestivum L.). Mineff was defined as the difference between crop N uptake (Ncrop) at harvest and N supply. Our aim was the identification and quantification of climate and site-related factors in order to achieve an improved assessment of the site-specific (long term average) Mineff. We used N rate experiments from 411 collective seasons, carried out at 98 sites across Germany in order to analyze the impact of climate and site-related factors on Mineff. Quadratic curves were fitted in order to describe the grain N uptake as a function of N supply. A fixed marginal N efficiency was defined in order to analyze Mineff at a reasonable N supply. Starting with estimates for Mineff as function of preceding crop, we found that climate (average temperature during May, annual rainfall) and site-related factors have a significant influence on Mineff. In order to ensure that the regression model is transferable to unknown sites, a “leave one site out” cross validation was carried out. Compared to considering preceding crop only (reference), the regression model reduced the RMSE by 9.5 (calibration) or 8.3 (cross validation) kg N/ha. 相似文献