Read by QxMD icon Read


Shanshan Zhang, Qingfen Niu, Tao Sun, Yang Li, Tianduo Li, Haixia Liu
A novel linear A-π-D-π-A-type organic small molecule Ph2(PDPP)2 consisting diketopyrrolopyrrole (DPP) as acceptor unit, biphenylene as donor unit and acetylene unit as π-linkage has been successfully designed and synthesized. Its corresponding thermal, photophysical and electrochemical properties as well as the photoinduced charge-separation process were investigated. Ph2(PDPP)2 exhibits high thermal stability and it can be soluble in common organic solvents such as chloroform and tetrahydrofuran. The photophysical properties show that DPP2Ph2 harvests sunlight over the entire visible spectrum range in the thin-film state (300-800nm)...
April 20, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Amita Ummadisingu, Ludmilla Steier, Ji-Youn Seo, Taisuke Matsui, Antonio Abate, Wolfgang Tress, Michael Grätzel
Optimizing the morphology of metal halide perovskite films is an important way to improve the performance of solar cells when these materials are used as light harvesters, because film homogeneity is correlated with photovoltaic performance. Many device architectures and processing techniques have been explored with the aim of achieving high-performance devices, including single-step deposition, sequential deposition and anti-solvent methods. Earlier studies have looked at the influence of reaction conditions on film quality, such as the concentration of the reactants and the reaction temperature...
April 26, 2017: Nature
Yujuan He, Ki-Joong Kim, Chih-Hung Alex Chang
Hollow silica nanoparticles (HSNPs) were synthesized using a microreactor-assisted system with a hydrodynamic focusing micromixer (HFM). Due to the fast mixing of each precursor in the system, the PAA thermodynamic-locked (TML) conformations were protected from their random aggregations by the immediately initiated growth of silica shells. When altering the mixing time through varying flow rates and flow rate ratios, the different degrees of the aggregation of PAA TML conformations were observed. The globular and necklace-like TML conformations were successfully captured by modifying the PAA concentration at the optimized mixing condition...
April 26, 2017: Nanotechnology
Zhiguo Xia, Kenneth R Poeppelmeier
Adaptable crystalline frameworks are important in modern solid-state chemistry as they are able to accommodate a wide range of elements, oxidation states, and stoichiometries. Owing to this ability, such adaptable framework structures are emerging as the prototypes for technologically important advanced functional materials. In this Account, the idea of cosubstitution is explored as a useful "pairing" concept that can potentially lead to the creation of many new members of one particular framework structure...
April 25, 2017: Accounts of Chemical Research
Luca Passoni, Francesco Fumagalli, Andrea Perego, Sebastiano Bellani, Piero Mazzolini, Fabio di Fonzo
Monolithic dye sensitized solar cell architectures hold great potential for building integrated photovoltaics applications. They indeed benefit from lower weight and manufacturing costs as they avoid the use of a transparent conductive oxide coated glass counter electrode. In this work a transparent monolithic dye-sensitized solar cell comprising hierarchical 1D nanostructures stack is fabricated by physical vapour deposition techniques. The proof of concept device comprises hyperbranched TiO<sub>2 </sub> nanostructures, sensitized by the prototypical N719, as photoanode, a hierarchical nanoporous Al<sub>2 </sub>O<sub>3 </sub> spacer and a microporous ITO top electrode...
April 25, 2017: Nanotechnology
Gibum Kwon, Divya Panchanathan, Seyed Reza Mahmoudi, Mohammed A Gondal, Gareth H McKinley, Kripa K Varanasi
Photoresponsive titania surfaces are of great interest due to their unique wettability change upon ultraviolet light illumination. However, their applications are often limited either by the inability to respond to visible light or the need for special treatment to recover the original wettability. Sensitizing TiO2 surfaces with visible light-absorbing materials has been utilized in photovoltaic applications. Here we demonstrate that a dye-sensitized TiO2 surface can selectively change the wettability towards contacting liquids upon visible light illumination due to a photo-induced voltage across the liquid and the underlying surface...
April 25, 2017: Nature Communications
Carrie L McCarthy, Richard L Brutchey
Macroelectronics is a major focus in electronics research and is driven by large area applications such as flat panel displays and thin film solar cells. Innovations for these technologies, such as flexible substrates and mass production, will require efficient and affordable semiconductor processing. Low-temperature solution processing offers mild deposition methods, inexpensive processing equipment, and the possibility of high-throughput processing. In recent years, the discovery that binary "alkahest" mixtures of ethylenediamine and short chain thiols possess the ability to dissolve bulk inorganic materials to yield molecular inks has lead to the wide study of such systems and the straightforward recovery of phase pure crystalline chalcogenide thin films upon solution processing and mild annealing of the inks...
April 25, 2017: Chemical Communications: Chem Comm
Evgheni Strelcov, Qingfeng Dong, Tao Li, Jungseok Chae, Yuchuan Shao, Yehao Deng, Alexei Gruverman, Jinsong Huang, Andrea Centrone
Ferroelectricity has been proposed as a plausible mechanism to explain the high photovoltaic conversion efficiency in organic-inorganic perovskites; however, convincing experimental evidence in support of this hypothesis is still missing. Identifying and distinguishing ferroelectricity from other properties, such as piezoelectricity, ferroelasticity, etc., is typically nontrivial because these phenomena can coexist in many materials. In this work, a combination of microscopic and nanoscale techniques provides solid evidence for the existence of ferroelastic domains in both CH3NH3PbI3 polycrystalline films and single crystals in the pristine state and under applied stress...
April 2017: Science Advances
Yuqin Liao, Hefei Liu, Wenjia Zhou, Dongwen Yang, Yuequn Shang, Zhifang Shi, Binghan Li, Xianyuan Jiang, Lijun Zhang, Li Na Quan, Rafael Quintero-Bermudez, Brandon R Sutherland, Qixi Mi, Edward H Sargent, Zhijun Ning
The low toxicity and a near-ideal choice of bandgap make tin (Sn) perovskite an attractive alternative to lead perovskite in low cost solar cells. However, the development of Sn perovskite solar cells has been impeded by their extremely poor stability when exposed to oxygen. We report low-dimensional Sn perovskites that exhibit markedly-enhanced air stability in comparison with their 3D counterparts. The reduced degradation under air exposure is attributed to the improved thermodynamic stability after dimensional reduction, the encapsulating organic ligands, and the compact perovskite film preventing oxygen ingress...
April 24, 2017: Journal of the American Chemical Society
Robin Vismara, Olindo Isabella, Miro Zeman
We present the optical investigation of a novel back-contacted architecture for solar cells based on a thin barium (di)silicide (BaSi<sub>2</sub>) absorber. First, through the analysis of absorption limits of different semiconducting materials, we show the potential of BaSi<sub>2</sub> for photovoltaic applications. Then, the proposed back contacted BaSi<sub>2</sub> solar cell design is investigated and optimized. An implied photocurrent density of 40.3 mA/cm<sup>2</sup> in a 1-μm thick absorber was achieved, paving the way for novel BaSi<sub>2</sub>-based thin-film solar cells...
April 17, 2017: Optics Express
Haejun Chung, Xingshu Sun, Aditya D Mohite, Rahul Singh, Lokendra Kumar, Muhammad A Alam, Peter Bermel
A key challenge in photovoltaics today is to develop cell technologies with both higher efficiencies and lower fabrication costs than incumbent crystalline silicon (c-Si) single-junction cells. While tandem cells have higher efficiencies than c-Si alone, it is generally challenging to find a low-cost, high-performance material to pair with c-Si. However, the recent emergence of 22% efficient perovskite photovoltaics has created a tremendous opportunity for high-performance, low-cost perovskite / crystalline silicon tandem photovoltaic cells...
April 17, 2017: Optics Express
Wei Chen, Shiqiang Luo, Zunyuan Wan, Xiyuan Feng, Xinke Liu, Zhubing He
As it already made huge effect in the commercialization of silicon and other photovoltaics, interface engineering is dispensable in the current and future evolution of hybrid perovskite solar cells (PSCs) techniques. In order to solve carriers' recombination and detention at the cathode side of planar PSCs, in this work, Ruthenium acetylacetonate (RuAcac) was successfully adopted as a reliable and stable cathode interfacial layer (CIL) to improve the inverted planar PSCs. The power conversion efficiency of the optimal devices was enhanced from 12...
April 17, 2017: Optics Express
Miki Osaka, Daisuke Mori, Hiroaki Benten, Hiroki Ogawa, Hideo Ohkita, Shinzaburo Ito
Charge transport in intermixed regions of all-polymer solar cells based on a blend of poly(3-hexylthiophene) (P3HT; electron donor) with poly[2,7-(9,9-didodecylfluorene)-alt-5,5-(4',7'-bis(2-thienyl)-2',1',3'-benzothiadiazole)] (PF12TBT; electron acceptor) was studied by conductive atomic force microscopy (C-AFM). For a blend film fabricated from a chlorobenzene solution, intermixed regions were detected between the P3HT-rich and PF12TBT-rich domains. The overall hole current in the intermixed regions remained almost constant, both before and after thermal annealing at 80 C, but it increased in the P3HT-rich domains...
April 24, 2017: ACS Applied Materials & Interfaces
Claudia Ojeda-Aristizabal, Elton J G Santos, Seita Onishi, Aiming Yan, Haider Imad Rasool, Salman Kahn, Yinchuan Lv, Drew Latzke, Jairo Velasco, Michael F Crommie, Matthew Sorensen, Kenneth Gotlieb, Chiu-Yun Lin, Kenji Watanabe, Takashi Taniguchi, Alessandra Lanzara, Alex Zettl
Charge transfer at the interface between dissimilar materials is at the heart of electronics and photovoltaics. Here we study the molecular orientation, electronic structure, and local charge transfer at the interface region of C60 deposited on graphene, with and without supporting substrates such as hexagonal boron nitride. We employ ab initio density functional theory with van der Waals (vdW) interactions, and experimentally characterize interface devices using high-resolution transmission electron microscopy and electronic transport...
April 24, 2017: ACS Nano
Nicklas Anttu, Vilgailė Dagytė, Xulu Zeng, Gaute Otnes, Magnus Borgström
III-V semiconductor nanowires are a platform for next-generation photovoltaics. An interesting research direction is to embed a nanowire array in a transparent polymer, either to act as a stand-alone flexible solar cell, or to be stacked on top of a conventional Si bottom cell to create a tandem structure. To optimize the tandem cell performance, high energy photons should be absorbed in the nanowires whereas low energy photons should be transmitted to and absorbed in the Si cell. Here, through optical measurements on 1...
May 19, 2017: Nanotechnology
Max Jerneck
The article investigates how financialization impedes climate change mitigation by examining its effects on the early history of one low-carbon industry, solar photovoltaics in the United States. The industry grew rapidly in the 1970s, as large financial conglomerates acquired independent firms. While providing needed financial support, conglomerates changed the focus from existing markets in consumer applications toward a future utility market that never materialized. Concentration of the industry also left it vulnerable to the corporate restructuring of the 1980s, when the conglomerates were dismantled and solar divisions were pared back or sold off to foreign firms...
March 2017: Science Advances
Munkhbayar Batmunkh, Thomas J Macdonald, Cameron J Shearer, Munkhjargal Bat-Erdene, Yun Wang, Mark J Biggs, Ivan P Parkin, Thomas Nann, Joseph G Shapter
1D semiconducting oxides are unique structures that have been widely used for photovoltaic (PV) devices due to their capability to provide a direct pathway for charge transport. In addition, carbon nanotubes (CNTs) have played multifunctional roles in a range of PV cells because of their fascinating properties. Herein, the influence of CNTs on the PV performance of 1D titanium dioxide nanofiber (TiO2 NF) photoelectrode perovskite solar cells (PSCs) is systematically explored. Among the different types of CNTs, single-walled CNTs (SWCNTs) incorporated in the TiO2 NF photoelectrode PSCs show a significant enhancement (≈40%) in the power conversion efficiency (PCE) as compared to control cells...
April 2017: Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
Young-Kwang Jung, Ji-Hwan Lee, Aron Walsh, Aloysius Soon
CsSnI3 is a potential lead-free inorganic perovskite for solar energy applications due to its nontoxicity and attractive optoelectronic properties. Despite these advantages, photovoltaic cells using CsSnI3 have not been successful to date, in part due to low stability. We demonstrate how gradual substitution of Rb for Cs influences the structural, thermodynamic, and electronic properties on the basis of first-principles density functional theory calculations. By examining the effect of the Rb:Cs ratio, we reveal a correlation between octahedral distortion and band gap, including spin-orbit coupling...
April 11, 2017: Chemistry of Materials: a Publication of the American Chemical Society
Šarūnas Meškinis, Domantas Peckus, Andrius Vasiliauskas, Arvydas Čiegis, Rimantas Gudaitis, Tomas Tamulevičius, Iryna Yaremchuk, Sigitas Tamulevičius
Ultrafast relaxation dynamics of diamond-like carbon (DLC) films with embedded Ag nanoparticles (DLC:Ag) and photovoltaic properties of heterojunctions consisting of DLC:Ag and crystalline silicon (DLC:Ag/Si) were investigated by means of transient absorption (TAS) spectroscopy and photovoltaic measurements. The heterojunctions using both p type and n type silicon were studied. It was found that TAS spectra of DLC:Ag films were dependent on the used excitation wavelength. At wavelengths where Ag nanoparticles absorbed light most intensively, only DLC signal was registered...
December 2017: Nanoscale Research Letters
G Krishnamurthy Grandhi, Ranjani Viswanatha
The success of heterostructure quantum dots in optoelectronic and photovoltaic applications is based on our understanding of photogenerated charge carrier localization. However, often the actual location of charge carriers in heterostructure semiconductors is quite different from their predicted positions leading to suboptimal results. In this work, photoluminescence of Cu doped heterostructures has been used to study the charge localization of alloys, inverse type I, type II, and quasi type II core/shell structures and graded alloys...
April 24, 2017: Journal of Physical Chemistry Letters
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"