Highlights
A comprehensive summary of the representative promising applications of metal halide perovskite materials, including traditional optoelectronic devices (solar cells, light-emitting diodes, ...photodetectors, lasers), and cutting-edge technologies in terms of neuromorphic devices (artificial synapses and memristors) and pressure-induced emission.
For each application, the fundamentals of the field, the current progress and the remaining challenges are provided, based on the up-to-date works.
Nowadays, the soar of photovoltaic performance of perovskite solar cells has set off a fever in the study of metal halide perovskite materials. The excellent optoelectronic properties and defect tolerance feature allow metal halide perovskite to be employed in a wide variety of applications. This article provides a holistic review over the current progress and future prospects of metal halide perovskite materials in representative promising applications, including traditional optoelectronic devices (solar cells, light-emitting diodes, photodetectors, lasers), and cutting-edge technologies in terms of neuromorphic devices (artificial synapses and memristors) and pressure-induced emission. This review highlights the fundamentals, the current progress and the remaining challenges for each application, aiming to provide a comprehensive overview of the development status and a navigation of future research for metal halide perovskite materials and devices.
Robust Color Guided Depth Map Restoration Liu, Wei; Chen, Xiaogang; Yang, Jie ...
IEEE transactions on image processing,
2017-Jan., 2017-Jan, 2017-1-00, 20170101, Letnik:
26, Številka:
1
Journal Article
Recenzirano
One of the most challenging issues in color guided depth map restoration is the inconsistency between color edges in guidance color images and depth discontinuities on depth maps. This makes the ...restored depth map suffer from texture copy artifacts and blurring depth discontinuities. To handle this problem, most state-of-the-art methods design complex guidance weight based on guidance color images and heuristically make use of the bicubic interpolation of the input depth map. In this paper, we show that using bicubic interpolated depth map can blur depth discontinuities when the upsampling factor is large and the input depth map contains large holes and heavy noise. In contrast, we propose a robust optimization framework for color guided depth map restoration. By adopting a robust penalty function to model the smoothness term of our model, we show that the proposed method is robust against the inconsistency between color edges and depth discontinuities even when we use simple guidance weight. To the best of our knowledge, we are the first to solve this problem with a principled mathematical formulation rather than previous heuristic weighting schemes. The proposed robust method performs well in suppressing texture copy artifacts. Moreover, it can better preserve sharp depth discontinuities than previous heuristic weighting schemes. Through comprehensive experiments on both simulated data and real data, we show promising performance of the proposed method.
Heteroarenes are important structural motif in functional molecules. A MnI‐catalyzed 1,2‐diheteroarylation of allenes via a C−H activation/Smiles rearrangement cascade is presented. The reaction ...occurred under additive‐free or even solvent‐free conditions, which allowed the creation of two C−C and one C−N bonds in a single operation. A series of structurally diverse bicyclic or tricyclic compounds bearing an exocyclic double bond were constructed in good to excellent efficiency. The decarboxylative ring‐opening of the products led to the facile synthesis of vicinal biheteroaryls. Synthetic applications were demonstrated and preliminary mechanistic studies were conducted.
Diheteroarylation of allenes: A MnI‐catalyzed C−H activation/Smiles rearrangement cascade enabled an unprecedented 1,2‐diheteroarylation of allenes. The reaction occurred under additive‐free or even solvent‐free conditions. A series of diverse bicyclic or tricyclic compounds bearing a valuable exocyclic double bond were constructed. The decarboxylative ring‐opening of the products led to the facile synthesis of vicinal biheteroaryl compounds.
High ion selectivity and permeability, as two contradictory aspects for the membrane design, highly hamper the development of osmotic energy harvesting technologies. Metal–organic frameworks (MOFs) ...with ultra‐small and high‐density pores and functional surface groups show great promise in tackling these problems. Here, we propose a facile and mild cathodic deposition method to directly prepare crack‐free porphyrin MOF membranes on a porous anodic aluminum oxide for osmotic energy harvesting. The abundant carboxyl groups of the functionalized porphyrin ligands together with the nanoporous structure endows the MOF membrane with high cation selectivity and ion permeability, thus a large output power density of 6.26 W m−2 is achieved. The photoactive porphyrin ligands further lead to an improvement of the power density to 7.74 W m−2 upon light irradiation. This work provides a promising strategy for the design of high‐performance osmotic energy harvesting systems.
A porphyrin metal–organic framework membrane has been fabricated by a facile cathodic deposition method. The high ion selectivity and permeability endow the MOF membrane with a great performance in osmotic energy harvesting, and this performance can be further improved by the photoactive porphyrin ligands upon light irradiation.
We have investigated the influence of multimode fiber core (MMFC) diameters and lengths on the sensitivity of an SMS fiber based refractometer. We show that the MMFC diameter has significant ...influence on the refractive index (RI) sensitivity but the length does not. A refractometer with a lower MMFC diameter has a higher sensitivity. Experimental investigations achieved a maximum sensitivity of 1815 nm/ RIU (refractive index unit) for a refractive index range from 1.342 to 1.437 for a refractometer with a core diameter of 80 μm. The experimental results fit well with the numerical simulation results.
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The power conversion efficiency for single-junction solar cells is limited by the Shockley-Quiesser limit. An effective approach to realize high efficiency is to develop ...multi-junction cells. These years have witnessed the rapid development of organic–inorganic perovskite solar cells. The excellent optoelectronic properties and tunable bandgaps of perovskite materials make them potential candidates for developing tandem solar cells, by combining with silicon, Cu(In,Ga)Se2 and organic solar cells. In this review, we present the recent progress of perovskite-based tandem solar cells, including perovskite/silicon, perovskite/perovskite, perovskite/Cu(In,Ga)Se2, and perovskite/organic cells. Finally, the challenges and opportunities for perovskite-based tandem solar cells are discussed.
This study considered all articles published in six Public Library of Science (PLOS) journals in 2012 and Web of Science citations for these articles as of May 2015. A total of 2,406 articles were ...analyzed to examine the relationships between Altmetric Attention Scores (AAS) and Web of Science citations. The AAS for an article, provided by Altmetric aggregates activities surrounding research outputs in social media (news outlet mentions, tweets, blogs, Wikipedia, etc.). Spearman correlation testing was done on all articles and articles with AAS. Further analysis compared the stratified datasets based on percentile ranks of AAS: top 50%, top 25%, top 10%, and top 1%. Comparisons across the six journals provided additional insights. The results show significant positive correlations between AAS and citations with varied strength for all articles and articles with AAS (or social media mentions), as well as for normalized AAS in the top 50%, top 25%, top 10%, and top 1% datasets. Four of the six PLOS journals, Genetics, Pathogens, Computational Biology, and Neglected Tropical Diseases, show significant positive correlations across all datasets. However, for the two journals with high impact factors, PLOS Biology and Medicine, the results are unexpected: the Medicine articles showed no significant correlations but the Biology articles tested positive for correlations with the whole dataset and the set with AAS. Both journals published substantially fewer articles than the other four journals. Further research to validate the AAS algorithm, adjust the weighting scheme, and include appropriate social media sources is needed to understand the potential uses and meaning of AAS in different contexts and its relationship to other metrics.
Light‐harvesting and charge collection have attracted increasing attention in the domain of photovoltaic cells, and can be facilitated dramatically by appropriate design of a photonic nanostructure. ...However, the applicability of current light‐harvesting photoanode materials with single component and/or morphology (such as, particles, spheres, wires, sheets) is still limited by drawbacks such as insufficient electron–hole separation and/or light‐trapping. Herein, we introduce a universal method to prepare hierarchical assembly of macroporous material–nanowire coated homogenous or heterogeneous metal oxide composite electrodes (TiO2–TiO2, SnO2–TiO2, and Zn2SnO4–TiO2; homogenous refers to a material in which the nanowire and the macroporous material have the same composition, i.e. both are TiO2. Heterogeneous refers to a material in which the nanowires and the macroporous material have different compositions). The dye‐sensitized solar cell based on a TiO2‐macroporous material–TiO2‐nanowire homogenous composition electrode shows an impressive conversion efficiency of 9.51 %, which is much higher than that of pure macroporous material‐based photoelectrodes to date.
Wired for light: A versatile method allows the preparation of nanowire‐coated macroporous material based homo‐ or heterogeneous metal oxide composite electrodes (TiO2–TiO2, SnO2–TiO2, and Zn2SnO4–TiO2). Dye‐sensitized solar cells based on macroporous TiO2/TiO2 nanowire homogeneous electrode show an impressive conversion efficiency as high as 9.51 %, which is much higher than those of pure macroporous material based photoelectrodes used up to date.
The vertically oriented anatase single crystalline TiO2 nanostructure arrays (TNAs) consisting of TiO2 truncated octahedrons with exposed {001} facets or hierarchical TiO2 nanotubes (HNTs) consisting ...of numerous nanocrystals on Ti-foil substrate were synthesized via a two-step hydrothermal growth process. The first step hydrothermal reaction of Ti foil and NaOH leads to the formation of H-titanate nanowire arrays, which is further performed the second step hydrothermal reaction to obtain the oriented anatase single crystalline TiO2 nanostructures such as TiO2 nanoarrays assembly with truncated octahedral TiO2 nanocrystals in the presence of NH4F aqueous or hierarchical TiO2 nanotubes with walls made of nanocrystals in the presence of pure water. Subsequently, these TiO2 nanostructures were utilized to produce dye-sensitized solar cells in a backside illumination pattern, yielding a significant high power conversion efficiency (PCE) of 4.66% (TNAs, J(SC) = 7.46 mA cm(-2), V(OC) = 839 mV, FF = 0.75) and 5.84% (HNTs, J(SC) = 10.02 mA cm(-2), V(OC) = 817 mV, FF = 0.72), respectively.
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•Co-pyrolysis of sewage sludge and sawdust/rice straw for biochars was conducted.•The yield of biochars decreased, while the content of organic matters increased.•Thermal stability, ...surface area, and pore volume of biochars were decreased.•The total contents of heavy metals in biochar products were reduced as expected.•The mobility of heavy metals in biochars was not alleviated.
Sewage sludge (SS) has been proved to be a good feedstock material for the production of biochars. However, the problem is that the total/leachable contents of some heavy metal elements in biochar products exceed the corresponding norms. In this work, efforts were made to solve above the mentioned topic through the addition of other biomasses (rice straw (RS) and sawdust (SD)) for the co-pyrolysis with SS. The addition of RS/SD reduced the yield of biochars, while the contents of organic matter in biochars were significantly improved. In addition, the introduction of biomasses, and especially the addition of SD, caused a decrease in the thermal stability, surface area, and pore volume of biochars. The total contents of heavy metals in biochar products, especially their Cu, Zn and Ni contents, were reduced as expected. However, reduction of the mobility of heavy metals in biochars according to the toxicity characteristic leaching procedure was not observed.
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