Arrays of ZnO/AZO (Al-doped ZnO) nanocables: a higher open circuit voltage and remarkable improvement of efficiency for CdS-sensitized solar cells

Jianping Deng; Minqiang Wang; Jing Liu; Xiaohui Song; Zhi Yang

doi:10.1016/j.jcis.2013.11.017

Arrays of ZnO/AZO (Al-doped ZnO) nanocables: a higher open circuit voltage and remarkable improvement of efficiency for CdS-sensitized solar cells

J Colloid Interface Sci. 2014 Mar 15:418:277-82. doi: 10.1016/j.jcis.2013.11.017. Epub 2013 Nov 21.

Authors

Jianping Deng¹, Minqiang Wang², Jing Liu¹, Xiaohui Song¹, Zhi Yang¹

Affiliations

¹ Electronic Materials Research Laboratory (EMRL), Key Laboratory of Education Ministry, International Center for Dielectric Research, Xi'an Jiaotong University, Xi'an 710049, China.
² Electronic Materials Research Laboratory (EMRL), Key Laboratory of Education Ministry, International Center for Dielectric Research, Xi'an Jiaotong University, Xi'an 710049, China. Electronic address: mqwang@mail.xjtu.edu.cn.

PMID: 24461846
DOI: 10.1016/j.jcis.2013.11.017

Abstract

Photoelectrode of nanocables (NCs) structure of ZnO nanowires (NWs) coated with Al-doped ZnO (AZO) shells was investigated for CdS quantum dots sensitized solar cells (QDSSCs). ZnO NWs serve as the frame for the preparation of AZO shells, in which electron transport more rapidly due to the more higher electron mobility of AZO (n-ZnO) than that of i-ZnO. AZO shells were assembled onto the surface of ZnO NWs via a spin-coating method. Optical band-gap of the ZnO/AZO films varies from 3.19 eV for pure ZnO to 3.25 eV for AZO (15%) depending on the Al-doping concentration. The PL intensity of AZO/ZnO, V(oc), J(sc) and η of the cells first increased and then decreased with the increase in the Al-doping (from 0% to 20%) and post-annealed temperature. Remarkably, the value of V(oc) can achieve above 0.8 V after Al-doping. The dark current and absorption spectrum provided direct evidence of the increase in J(sc) and V(oc), respectively. Moreover, we discussed the effect of Al-doping on optical band-gap of the samples and the transfer of electron.

Keywords: Al-doped ZnO; Core-shell; QDs-sensitized; Soar cells.