Valence Band Edge Shifts and Charge-transfer Dynamics in Li-Doped NiO Based p-type DSSCs

被引:42
作者
Wei, Lifang [1 ]
Jiang, Linpeng [1 ]
Yuan, Shuai [1 ]
Ren, Xin [1 ]
Zhao, Yin [1 ]
Wang, Zhuyi [1 ]
Zhang, Meihong [1 ]
Shi, Liyi [1 ]
Li, Dongdong [2 ]
机构
[1] Shanghai Univ, Res Ctr Nanosci & Nanotechnol, 99 Shangda Rd, Shanghai 200444, Peoples R China
[2] Chinese Acad Sci, Shanghai Adv Res Inst, Div Energy & Environm Res, Shanghai 201203, Peoples R China
基金
上海市自然科学基金; 中国国家自然科学基金;
关键词
Li-doped NiO photoelectrode; interfacial; photoelectrochemical; p-type DSSCs; SENSITIZED SOLAR-CELLS; DENSITY-OF-STATES; NICKEL-OXIDE NANOPARTICLES; IMPEDANCE SPECTROSCOPY; PERFORMANCE; ELECTRON; RECOMBINATION; TRANSPORT; CONDUCTIVITY; SURFACE;
D O I
10.1016/j.electacta.2015.12.026
中图分类号
O646 [电化学、电解、磁化学];
学科分类号
081704 ;
摘要
The objective of this work is to gain deeper insight into behavior of p-type DSSCs, paying special attention to photoelectric properties of Li-doped NiO photoelectrode, and studying their effect on interfacial photoelectrochemical processes under illumination and device performance. Here we find that Li-doped NiO photoelectrodes show higher charge carrier densities, down-shift of valence band and narrowing trap energy distribution. Furthermore, the performance enhancement of p-type DSSCs is observed for the Li-doped NiO photoelectrodes with respect to the unmodified ones. These improvement is found to arise from more rapid hole transport combined with reduced recombination, contributing to improved hole collection. With regard to interfacial carriers transfer process, electrochemical impedance spectroscopy (EIS), intensity-modulated photovoltage spectroscopy (IMPS) and ultra-violet photoemission spectra (UPS) provide evidence that the decreased recombination of Li-doped NiO DSSCs is attributed to the downward shift of valence band, which increases energy barrier of interface recombination. Another reason results in narrowing trap energy distribution of Li-doped NiO photoelectrode, which can weaken energy overlap with the LUMO level of dye, and subsequently the recombination path of hole back transfer to dye is hindered. These findings suggest that it will be important to carefully optimize band edge alignment and trap states distribution of p-type oxide semiconductors film to further improve the efficiency of p-DSSCs. (C) 2015 Elsevier Ltd. All rights reserved.
引用
收藏
页码:309 / 316
页数:8
相关论文
共 52 条
[1]   Electrochemical Assessment of the Band-Edge Positioning in Shape-Tailored TiO2-Nanorod-Based Photoelectrodes for Dye Solar Cells [J].
Agosta, Rita ;
Giannuzzi, Roberto ;
De Marco, Luisa ;
Manca, Michele ;
Belviso, Maria R. ;
Cozzoli, P. Davide ;
Gigli, Giuseppe .
JOURNAL OF PHYSICAL CHEMISTRY C, 2013, 117 (06) :2574-2583
[2]   Theoretical Insights into Photoinduced Charge Transfer and Catalysis at Oxide Interfaces [J].
Akimov, Alexey V. ;
Neukirch, Amanda J. ;
Prezhdo, Oleg V. .
CHEMICAL REVIEWS, 2013, 113 (06) :4496-4565
[3]  
[Anonymous], AIAA J
[4]   Factors controlling charge recombination under dark and light conditions in dye sensitised solar cells [J].
Barnes, Piers R. F. ;
Anderson, Assaf Y. ;
Juozapavicius, Mindaugas ;
Liu, Lingxuan ;
Li, Xiaoe ;
Palomares, Emilio ;
Forneli, Amparo ;
O'Regan, Brian C. .
PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 2011, 13 (08) :3547-3558
[5]   Relaxation of Electron Carriers in the Density of States of Nanocrystalline TiO2 [J].
Bertoluzzi, Luca ;
Herraiz-Cardona, Isaac ;
Gottesman, Ronen ;
Zaban, Arie ;
Bisquert, Juan .
JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 2014, 5 (04) :689-694
[6]   Tuning of Conductivity and Density of States of NiO Mesoporous Films Used in p-Type DSSCs [J].
D'Amario, Luca ;
Boschloo, Gerrit ;
Hagfeldt, Anders ;
Hammarstrom, Leif .
JOURNAL OF PHYSICAL CHEMISTRY C, 2014, 118 (34) :19556-19564
[7]   Band engineering of Ni1-xMgxO alloys for photocathodes of high efficiency dye-sensitized solar cells [J].
Deng, Junkai ;
Mortazavi, Majid ;
Medhekar, N. V. ;
Liu, Jefferson Zhe .
JOURNAL OF APPLIED PHYSICS, 2012, 112 (12)
[8]   Decoupling of transport, charge storage, and interfacial charge transfer in the nanocrystalline TiO2/electrolyte system by impedance methods [J].
Fabregat-Santiago, F ;
Garcia-Belmonte, G ;
Bisquert, J ;
Zaban, A ;
Salvador, P .
JOURNAL OF PHYSICAL CHEMISTRY B, 2002, 106 (02) :334-339
[9]   Correlation between photovoltaic performance and impedance spectroscopy of dye-sensitized solar cells based on ionic liquids [J].
Fabregat-Santiago, Francisco ;
Bisquert, Juan ;
Palomares, Emilio ;
Otero, Luis ;
Kuang, Daibin ;
Zakeeruddin, Shaik M. ;
Gratzel, Michael .
JOURNAL OF PHYSICAL CHEMISTRY C, 2007, 111 (17) :6550-6560
[10]   Ultrasmall Dispersible Crystalline Nickel Oxide Nanoparticles as High-Performance Catalysts for Electrochemical Water Splitting [J].
Fominykh, Ksenia ;
Feckl, Johann M. ;
Sicklinger, Johannes ;
Doeblinger, Markus ;
Boecklein, Sebastian ;
Ziegler, Juergen ;
Peter, Laurence ;
Rathousky, Jiri ;
Scheidt, Ernst-Wilhelm ;
Bein, Thomas ;
Fattakhova-Rohlfing, Dina .
ADVANCED FUNCTIONAL MATERIALS, 2014, 24 (21) :3123-3129