http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Yella, Aswani (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Delcamp, Jared H.,Yella, Aswani,Nazeeruddin, Mohammad K.,Grä,tzel, Michael The Royal Society of Chemistry 2012 Chemical communications Vol.48 No.17
<P>Acceptor motifs based on nitrogen containing heterocycles have been synthesized for use in dye-sensitized solar cells (DSCs). Through the selective addition of nitrogen atoms and increased conjugation of the nitrogen containing heterocycles the excited-state oxidation potential, <I>E</I><SUB>(S+/S*)</SUB>, may be conveniently tuned with minimal effect on the ground-state oxidation potential, <I>E</I><SUB>(S+/S)</SUB>, of the dye.</P> <P>Graphic Abstract</P><P>A series of nitrogen containing heterocyclic acceptors are shown to tune the excited-state oxidation potential of D-π-A dyes for DSCs. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cc17142b'> </P>
-
Robson, Kiyoshi C. D.,Koivisto, Bryan D.,Yella, Aswani,Sporinova, Barbora,Nazeeruddin, Mohammad K.,Baumgartner, Thomas,Grä,tzel, Michael,Berlinguette, Curtis P. American Chemical Society 2011 Inorganic Chemistry Vol.50 No.12
<P>The syntheses and the electrochemical spectroscopic properties of a suite of asymmetrical <I>bis</I>tridentate cyclometalated Ru(II) complexes bearing terminal triphenylamine (TPA) substituents are reported. These complexes, which contain structural design elements common to both inorganic and organic dyes that exhibit superior power conversion efficiencies in the dye-sensitized solar cell (DSSC), are broadly formulated as [Ru<SUP>II</SUP>(L-2,5′-thiophene-TPA-R<SUB>1</SUB>)(L-R<SUB>2</SUB>)]<SUP>+</SUP> [L = tridentate chelating ligand (e.g., 2,2′:6′,2′′-terpyridine (tpy); deprotonated forms of 1,3-di(pyridin-2-yl)benzene (Hdpb) or 6-phenyl-2,2′-bipyridine (Hpbpy)); R<SUB>1</SUB> = −H, −Me, −OMe; R<SUB>2</SUB> = −H, −CO<SUB>2</SUB>Me, −CO<SUB>2</SUB>H]. The following structural attributes were systematically modified for the series: (i) electron-donating character of the terminal substituents (e.g., R<SUB>1</SUB> = −H, −Me, −OMe) placed <I>para</I> to the amine of the “L-2,5′-thiophene-TPA-R<SUB>1</SUB>” ligand framework; (ii) electron-withdrawing character of the tridentate chelate distal to the TPA-substituted ligand (e.g., R<SUB>2</SUB> = −H, −CO<SUB>2</SUB>Me, −CO<SUB>2</SUB>H); and (iii) position of the organometallic bond about the Ru(II) center. UV–vis spectra reveal intense and broad absorption bands arising from a collection of metal-to-ligand charge-transfer (MLCT) and TPA-based intraligand charge-transfer (ILCT) transitions that, in certain cases, extend beyond 800 nm. Electrochemical data indicate that the oxidative behavior of the TPA and metal chelate units can be independently modulated except in cases where the anionic phenyl ring is in direct conjugation with the TPA unit. In most cases, the anionic character of the cyclometalating ligands renders a metal-based oxidation event prior to the oxidation of the TPA unit. This situation can, however, be reversed with an appropriately positioned Ru–C bond and electron-rich R<SUB>1</SUB> group. This finding is important in that this arrangement confines the highest occupied molecular orbital (HOMO) to the TPA unit rather than the metal, which is optimal for sensitizing TiO<SUB>2</SUB>; indeed, a remarkably high power conversion efficiency (η) in the DSSC (i.e., 8.02%) is measured for the TPA-substituted pbpy<SUP>–</SUP> chelate where R<SUB>1</SUB> = −OMe. These results provide a comprehensive strategy for improving the performance of <I>bis</I>tridentate Ru sensitizers devoid of NCS<SUP>–</SUP> groups for the DSSC.</P><P>A series of bichromic cyclometalated <I>bis</I>tridentate Ru(II) complexes containing a triphenylamine-based donor unit produce broad, intense absorbance profiles. The ability to modulate the redox behavior of each of the chromophore units independently was exploited to converge on a high-performance class of dyestuff devoid of NCS<SUP>−</SUP> ligands.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/inocaj/2011/inocaj.2011.50.issue-12/ic200011m/production/images/medium/ic-2011-00011m_0012.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ic200011m'>ACS Electronic Supporting Info</A></P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
