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Liu X.,Tianjin University | Zhang F.,Tianjin University | Sun M.,Tianjin University | Wang S.,Tianjin University | And 3 more authors.
Journal of Energy Chemistry | Year: 2016

Two electron-rich, solution-processable phenonaphthazine derivatives, 5,12-bis(N-[4,4'-bis-(phenyl) -aminophen-4''-yl])-phenonaphthazine (BPZTPA) and 5,12-bis(N-[4,4'-bis(methoxy-phenyl)aminophen-4''-yl]) -phenonaphthazine (MeO-BPZTPA) have been designed and employed in the fabrication of perovskite solar cells. BPZTPA and MeO-BPZTPA exhibit excellent thermal stabilities, hole mobilities (∼10-4 cm2/(V .s)) and suitable HOMO levels (-5.34 and -5.29eV, respectively) relative to the valence band of the CH3NH3PbI3 and Au work function, showing their potential as alternative hole-transporting materials (HTMs). Meanwhile, the corresponding mesoporous TiO2/CH3NH3PbI3/HTM/Au devices are investigated, and the best power conversion efficiency of 10.36% has been achieved for MeO-BPZTPA without using p-type dopant. © 2016. Source

Shi J.,Chinese Academy of Sciences | Shi J.,Beijing Key Laboratory for New Energy Materials and Devices | Shi J.,CAS Institute of Physics | Xu X.,Chinese Academy of Sciences | And 8 more authors.
Small | Year: 2015

The interfacial atomic and electronic structures, charge transfer processes, and interface engineering in perovskite solar cells are discussed in this review. An effective heterojunction is found to exist at the window/perovskite absorber interface, contributing to the relatively fast extraction of free electrons. Moreover, the high photovoltage in this cell can be attributed to slow interfacial charge recombination due to the outstanding material and interfacial electronic properties. However, some fundamental questions including the interfacial atomic and electronic structures and the interface stability need to be further clarified. Designing and engineering the interfaces are also important for the next-stage development of this cell. Interfaces in perovskite solar cells are reviewed and discussed as an approach to understand the origin of the remarkable performance in this semiconductor photovoltaic device, in which the interfacial atomic and electronic structures, charge dynamics, and interface engineering are included. This review shows the importance of the interfaces and brings a better understanding to the workings of this cell. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Zhao E.,Harbin Institute of Technology | Ma C.,CAS Institute of Physics | Ma C.,Chinese Academy of Sciences | Ma C.,Beijing Key Laboratory for New Energy Materials and Devices | And 10 more authors.
International Journal of Hydrogen Energy | Year: 2013

In order to reduce the polarization resistance of the cathode, we have developed one-dimensional (1D) nanostructured La0.8Sr 0.2Co0.2Fe0.8O3-δ (LSCF) tubes/Ce0.8Gd0.2O1.9 (GDC) nanoparticles composite cathodes for solid oxide fuel cell. Uniform LSCF/PVP composite nanofibers have been firstly synthesized by a single-nozzle electrospinning technique, followed by firing at 800 C for 2 h to form one-dimensional LSCF tubes. Subsequently, the GDC phases were introduced into tube structured LSCF scaffold pre-sintered on a GDC pellet by a multi-impregnation process. Electrochemical Impedance spectra reveal that nanostructured LSCF tubes/GDC nanoparticles composite cathodes have a better electrochemical performance, achieving area-specific resistances of 4.70, 1.12, 0.27 and 0.07 Ω cm 2 at 500, 550, 600 and 650 C for the composite of GDC and LSCF in a weight ratio of 0.52:1. The low ASR values are mainly related to its optimal microstructure with larger triple-phase boundaries and higher porosity. These results suggest that LSCF tube/GDC nanoparticle composite can be an alternative cathode material for intermediate temperature solid oxide fuel cell (IT-SOFC). © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Yang W.,CAS Institute of Physics | Yang W.,Chinese Academy of Sciences | Yang W.,Beijing Key Laboratory for New Energy Materials and Devices | Salim J.,Indiana University - Purdue University Indianapolis | And 12 more authors.
Electrochemistry Communications | Year: 2013

Porous flowerlike Co3O4 microspheres/Cu nanoparticles composite has been synthesized via a combined solvothermal method, subsequent thermal treatment and polyol process. Due to the 3D mesoporous structure, the resulting Co3O4 microspheres/Cu catalyst shows an efficient and stable bifunctional catalytic activity. The cobalt oxide-based catalysts show better performance during the discharging and charging processes at a current density of 0.05 mA cm- 2 compared with that of the Vulcan XC-72. The cell with this novel catalyst can be reversibly charged/discharged and has a good cycle performance. The preliminary results indicate that the Porous flowerlike Co3O4 microspheres/Cu nanoparticles composite is a promising material for a metal/air battery or a PEM fuel cell as an efficient and stable bifunctional catalyst. © 2012 Elsevier B.V. Source

Dong J.,Chinese Academy of Sciences | Dong J.,Beijing Key Laboratory for New Energy Materials and Devices | Dong J.,CAS Institute of Physics | Shi J.,Chinese Academy of Sciences | And 11 more authors.
Applied Physics Letters | Year: 2015

The mechanism of charge recombination at the interface of n-type electron transport layer (n-ETL) and perovskite absorber on the carrier properties in the perovskite solar cell is theoretically studied. By solving the one dimensional diffusion equation with different boundary conditions, it reveals that the interface charge recombination in the perovskite solar cell can be suppressed by adjusting the conduction band offset (ΔEC) at ZnO ETL/perovskite absorber interface, thus leading to improvements in cell performance. Furthermore, Mg doped ZnO nanorods ETL has been designed to control the energy band levels. By optimizing the doping amount of Mg, the conduction band minimum of the Mg doped ZnO ETL has been raised up by 0.29eV and a positive ΔEC of about 0.1eV is obtained. The photovoltage of the cell is thus significantly increased due to the relatively low charge recombination. © 2015 AIP Publishing LLC. Source

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