Shared posts

27 Oct 11:22

Electron energy loss spectroscopy for polymers: a review

Polym. Chem., 2017, 8,6927-6937
DOI: 10.1039/C7PY01459G, Review Article
Ruchi Pal, Arun K. Sikder, Kei Saito, Alison M. Funston, Jayesh R. Bellare
Electron energy loss spectroscopy (EELS) allows imaging as well as extraction of spatially resolved chemical information and this review presents how EELS can be ap plied to polymeric systems.
The content of this RSS Feed (c) The Royal Society of Chemistry
12 Sep 01:03

Probing Charge-State Distribution at Grain Boundaries Varied with Dopant Concentration for Ceria Ceramics

by Kiminori Sato

TOC Graphic

The Journal of Physical Chemistry C
DOI: 10.1021/acs.jpcc.7b07978
18 Aug 08:34

Low bandgap polymers based on bay-annulated indigo for organic photovoltaics: Enhanced sustainability in material design and solar cell fabrication

Publication date: November 2017
Source:Organic Electronics, Volume 50
Author(s): Jeroen Brebels, Karine C.C.W.S. Klider, Mathias Kelchtermans, Pieter Verstappen, Melissa Van Landeghem, Sabine Van Doorslaer, Etienne Goovaerts, Jarem R. Garcia, Jean Manca, Laurence Lutsen, Dirk Vanderzande, Wouter Maes
Although research in the field of organic photovoltaics (OPV) still merely focuses on efficiency, efforts to increase the sustainability of the production process and the materials encompassing the device stack are of equally crucial importance to fulfil the promises of a truly renewable source of energy. In this study, a number of steps in this direction are taken. The photoactive polymers all contain an electron-deficient building block inspired on the natural indigo dye, bay-annulated indigo, combined with electron-rich thiophene and 4H-dithieno[3,2-b:2′,3′-d]pyrrole units. The synthetic protocol (starting from indigo) is optimized and the final materials are thoroughly analyzed. MALDI-TOF mass spectrometry provides detailed information on the structural composition of the polymers. Best solar cell efficiencies are obtained for polymer:fullerene blends spin-coated from a pristine non-halogenated solvent (o-xylene), which is highly recommended to reduce the ecological footprint of OPV and is imperative for large scale production and commercialization.

Graphical abstract

image
18 Aug 08:33

Improved efficiency and stability in polymer solar cells using a Tetra-nuclear Zinc(II) complex interfacial layer

Publication date: November 2017
Source:Organic Electronics, Volume 50
Author(s): Xin-Yan Zhao, Ting Wang, Lu Wang, Xiangyu Zhang, Zui Tao, Bao Xiu Mi, Zhi Qiang Gao
Tetra-nuclear Zinc(II) complex Zn4O(AID)6 [AID = 7-azaindolate] is a wide band gap luminescent material that exhibits efficient emission matching the absorption spectra of organic donor materials such as polythiophene (P3HT). This work demonstrates polymer solar cells (PSC) based on P3HT:PCBM (phenyl-C61-butyric acid methyl ester) blend active layer with a Zn4O(AID)6 cathode interfacial layer achieving a power conversion efficiency (PCE) significantly higher than that of the reference devices. The energy level and impedance spectroscopy analysis show that the Zn4O(AID)6 cathode interfacial layer acts as an efficient exciton/hole blocking layer, and reduces charge recombination rate with more efficient electron extraction. The Zn4O(AID)6 interfacial layer also helps achieve longer lifetime of PSC devices. The improved efficiency and stability combined with low cost and nontoxicity of Zn4O(AID)6 make it a promising cathode interfacial material for high-performance and stable PSC devices.

Graphical abstract

image
18 Aug 08:33

Role of fullerene electron transport layer on the morphology and optoelectronic properties of perovskite solar cells

Publication date: November 2017
Source:Organic Electronics, Volume 50
Author(s): Mushfika Baishakhi Upama, Naveen Kumar Elumalai, Md Arafat Mahmud, Dian Wang, Faiazul Haque, Vinicius R. Gonçales, J. Justin Gooding, Matthew Wright, Cheng Xu, Ashraf Uddin
High performance, hysteresis-free, low temperature n-i-p perovskite solar cells are successfully fabricated by solution processing using fullerene electron transport layer (ETL). PC71BM fullerene, with broader absorption spectrum and lower HOMO level, when incorporated in the perovskite solar cell yielded average power conversion efficiency (PCE) of 13.9%. This is the highest reported PCE in n-i-p perovskite solar cells with PC71BM ETL. The devices exhibited negligible hysteresis and high open-circuit voltage (Voc). On the contrary, devices with PC61BM, a common fullerene ETL in perovskite solar cell, exhibited large hysteresis and lower Voc. The underlying mechanisms of superior performance of devices with PC71BM ETL were found to be correlated with fullerene surface wettability and perovskite grain size. The influence of fullerene ETL on the perovskite grain growth and subsequent photovoltaic performance was investigated by contact angle measurement, morphological characterization of the surface topography and electrochemical impedance analysis.

Graphical abstract

image
30 Jan 05:49

Two-Step Design of a Single-Doped White Phosphor with High Color Rendering

by Romain Gautier, Xueyan Li, Zhiguo Xia and Florian Massuyeau

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.6b12597
25 Aug 15:54

Implication of Fluorine Atom on Electronic Properties, Ordering Structures, and Photovoltaic Performance in Naphthobisthiadiazole-Based Semiconducting Polymers

by Kazuaki Kawashima, Tomohiro Fukuhara, Yousuke Suda, Yasuhito Suzuki, Tomoyuki Koganezawa, Hiroyuki Yoshida, Hideo Ohkita, Itaru Osaka and Kazuo Takimiya

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.6b05418
01 Jul 04:30

Acridinium Ester-Functionalized Carbon Nanomaterials: General Synthesis Strategy and Outstanding Chemiluminescence

by Zhili Han, Fang Li, Jiangnan Shu, Lingfeng Gao, Xiaoying Liu and Hua Cui

TOC Graphic

ACS Applied Materials & Interfaces
DOI: 10.1021/acsami.6b04055
07 Jun 14:48

High-Mobility ZnO Nanorod Field-Effect Transistors by Self-Alignment and Electrolyte-Gating

by Stefan Thiemann, Mathias Gruber, Irina Lokteva, Johannes Hirschmann, Marcus Halik and Jana Zaumseil

TOC Graphic

ACS Applied Materials & Interfaces DOI: 10.1021/am3026739
31 May 04:40

Twisted Thiophene-Based Chromophores with Enhanced Intramolecular Charge Transfer for Cooperative Amplification of Third-Order Optical Nonlinearity

by Natasha B. Teran, Guang S. He, Alexander Baev, Yanrong Shi, Mark T. Swihart, Paras N. Prasad, Tobin J. Marks and John R. Reynolds

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.5b12457
18 May 16:04

Decoupling Charge Transfer and Transport at Polymeric Hole Transport Layer in Perovskite Solar Cells

by Dong Hun Sin, Hyomin Ko, Sae Byeok Jo, Min Kim, Geun Yeol Bae and Kilwon Cho

TOC Graphic

ACS Applied Materials & Interfaces
DOI: 10.1021/acsami.5b12023
09 Mar 14:45

Rational design of diketopyrrolopyrrole-based oligomers with deep HOMO level and tunable liquid crystal behavior by modulating the sequence and strength of the donor moiety

J. Mater. Chem. C, 2015, 3,9849-9858
DOI: 10.1039/C5TC02385H, Paper
Jin-Liang Wang, Zheng-Feng Chang, Xiao-Xin Song, Kai-Kai Liu, Ling-Min Jing
A family of narrow-band gap [small pi]-conjugated oligomers and isomers based on diketopyrrolopyrrole and difluorobenzothiadiazole coupled with an oligothiophene or thiazole ring have been successfully synthesized.
The content of this RSS Feed (c) The Royal Society of Chemistry