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 : HAGFELDT (검색결과 4 건)
- 무료
- 기관 내 무료
- 유료
-
HIGH-EFFICIENT SOLID-STATE PEROVSKITE SOLAR CELL WITHOUT LITHIUM SALT IN THE HOLE TRANSPORT MATERIAL
DONGQIN BI,ANDERS HAGFELDT,GERRIT BOSCHLOO 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.5
CH 3 NH 3 PbX (X ¼ Br, I, Cl) perovskites have recently been used as light absorbers in hybridorganic – inorganic solid-state solar cells, with e±ciencies above 15%. To date, it is essential to addLithium bis(Tri°uoromethanesulfonyl)Imide (LiTFSI) to the hole transport materials (HTM) toget a higher conductivity. However, the detrimental e®ect of high LiTFSI concentration on thecharge transport, DOS in the conduction band of the TiO 2 substrate and device stability resultsin an overall compromise for a satisfactory device. Using a higher mobility hole conductor toavoid lithium salt is an interesting alternative. Herein, we successfully made an e±cient perov-skite solar cell by applying a hole conductor PTAA (Poly[bis(4-phenyl) (2,4,6-trimethylphenyl)-amine]) in the absence of LiTFSI. Under AM 1.5 illumination of 100 mW/cm2, an e±ciency of10.9% was achieved, which is comparable to the e±ciency of 12.3% with the addition of 1.3 mMLiTFSI. An unsealed device without Liþshows interestingly a promising stability.
-
EFFECT OF THE CHROMOPHORES STRUCTURES ON THE PERFORMANCE OF SOLID-STATE DYE SENSITIZED SOLAR CELLS
HAINING TIAN,Eva M. Barea,ANDREA SOTO,BO XU,LICHENG SUN,ANDERS HAGFELDT,FRANCISCO FABREGAT-SANTIAGO,IVAN MORA-SERO,강용수,Juan Bisquert 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.5
The efect of metal-free chromophores on dye-sensitized solar cell performance is investigated. Solid state dye-sensitized solar cells (ssDSCs) using diferent molecular sensitizers based on tri-phenylamine (TPA) with thiophene linkers and diferent alkyl chain in the donor unit have beencharacterized using impedance spectroscopy (IS). We show that diferent molecular structuresplay a fundamental role on solar cell performance, by the efect produced on TiO 2 conductionband position and in the recombination rate. Dye structure and its electronic properties are themain factors that control the recombination, the capacitance and the e±ciency of the cells. Aclear trend between the performance of the cell and the optimization level of the blocking efect of the dye structure has been identi¯ed in the solid state solar cells with Spiro-OMeTAD holeconductor.
-
Park, Byung-wook,Zhang, Xiaoliang,Johansson, Erik M.J.,Hagfeldt, Anders,Boschloo, Gerrit,Seok, Sang Il,Edvinsson, Tomas Elsevier 2017 Nano energy Vol.40 No.-
<P><B>Abstract</B></P> <P>Organic inorganic metal halide perovskites (OIHPs) has emerged as promising photovoltaic materials the latest years. Many OIHPs, however, have complex material compositions with mixed cation and halide compositions, phase mixtures, as well as beneficial remains of PbI<SUB>2</SUB> in the final solar cell materials where the complex material composition with dual conduction and valence band states and its effects on the performance remain unclear. Here, we report an approach to analyze the phase mixture, order-disorder phases and the emissive electronic states <I>via</I> a 4-state model of the photoluminescence yield. The approach is applied to scaffold layer perovskite materials with different mixed halide composition. The optical transitions and the full emission spectra are de-convoluted to quantify the band gaps and charge quenching yields in the OIHPs. An approach to extract the excited state coupling parameters within the 4-state model is also briefly given. The integration model is finally utilized in charge quenching yield analysis for the different materials and correlated with solar cell performance from MAPbI<SUB>3</SUB> and MAPbI<SUB>3−x</SUB>Cl<SUB>x</SUB> in mesoporous TiO<SUB>2</SUB> layers where inclusion of Cl improves crystal formation and is compared to alternative approaches using optimized solvents and anti-solvent methods. A band gap grading effect was found to be present for the scaffold MAPbI<SUB>3</SUB> and increased for MAPbI<SUB>3−x</SUB>Cl<SUB>x</SUB>, beneficial for decreased hole concentration at the back contact and thus reducing back contact recombination.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Analysis of structural order-disorder and the emissive electronic states <I>via</I> a 4-state model is presented. </LI> <LI> Charge quenching yield analysis of mixed halide perovskite materials. </LI> <LI> Crystallization behavior of Cl inclusion in MAPbI<SUB>3−x</SUB>Cl<SUB>x</SUB> is compared with low and high oxidation conditions in MAPbI<SUB>3</SUB>. </LI> <LI> Efficiencies of 13.1% and 15.5% are obtained for Cl-inclusion and up to 18.2% for MAPbI<SUB>3</SUB> using anti-solvent treatment. </LI> <LI> A band gap grading effect was found for the scaffold MAPbI<SUB>3</SUB> and MAPbI<SUB>3-x</SUB>Cl<SUB>x</SUB>, devices not present for the planar system. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>An approach to analyze the structural order-disorder phases and the emissive electronic states <I>via</I> a 4-state model of the photoluminescence yield is presented. Charge quenching yield analysis of mixed halide perovskite materials correlate well with the solar cell performance from MAPbI<SUB>3</SUB> and MAPbI<SUB>3−x</SUB>Cl<SUB>x</SUB> in mesoporous TiO<SUB>2</SUB> layers where a band gap grading effect was found, beneficial for suppressing back-contact recombination.</P> <P>[DISPLAY OMISSION]</P>
-
Guerrero, Antonio,Garcia-Belmonte, Germà,Mora-Sero, Ivan,Bisquert, Juan,Kang, Yong Soo,Jacobsson, T. Jesper,Correa-Baena, Juan-Pablo,Hagfeldt, Anders American Chemical Society 2016 The Journal of Physical Chemistry Part C Vol.120 No.15
<P>Impedance spectroscopy offers access to all the different electronic and ionic processes taking place simultaneously in an operating solar cell. To date, its use on perovskite solar cells has been challenging because of the richness of the physical processes occurring within similar time domains. The aim of this work is to understand the general impedance response and propose a general equivalent circuit model that accounts for the different processes and gives access to quantitative analysis. When the electron-selective contacts and the thickness of the perovskite film are systematically modified, it is possible to distinguish between the characteristic impedance signals of the perovskite layer and those arising from the contacts. The study is carried out using mixed organic lead halogen perovskite (FA(0.85)MA(0.15)Pb(I0.85Br0.15)(3)) solar cells with three different electron-selective contacts: SnO2, TiO2, and Nb2O5. The contacts have been deposited by atomic layer deposition (ALD), which provides pinhole-free films and excellent thickness control in the absence of a mesoporous layer to simplify the impedance analysis. It was found that the interfacial impedance has a rich structure that reveals different capacitive processes, serial steps for electron extraction, and a prominent inductive loop related to negative capacitance at intermediate frequencies. Overall, the present report provides insights into the impedance response of perovskite solar cells which enable an understanding of the different electronic and ionic processes taking place during device operation.</P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
