CdTe Nanocrystal Hetero-Junction Solar Cells with High Open Circuit Voltage Based on Sb-doped TiO₂ Electron Acceptor Materials

Miaozi Li; Xinyan Liu; Shiya Wen; Songwei Liu; Jingxuan Heng; Donghuan Qin; Lintao Hou; Hongbin Wu; Wei Xu; Wenbo Huang

doi:10.3390/nano7050101

CdTe Nanocrystal Hetero-Junction Solar Cells with High Open Circuit Voltage Based on Sb-doped TiO₂ Electron Acceptor Materials

Nanomaterials (Basel). 2017 May 3;7(5):101. doi: 10.3390/nano7050101.

Authors

Miaozi Li¹, Xinyan Liu², Shiya Wen³, Songwei Liu⁴, Jingxuan Heng⁵, Donghuan Qin⁶, Lintao Hou⁷, Hongbin Wu⁸, Wei Xu⁹, Wenbo Huang¹⁰

Affiliations

¹ School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China. limz4994@sina.com.
² School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China. liuxy0310@sina.com.
³ School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China. a740176840@163.com.
⁴ School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China. majestyv@sina.com.
⁵ School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China. hengjingxuan@163.com.
⁶ Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices, South China University of Technology, Guangzhou 510640, China. qindh@scut.edu.cn.
⁷ Siyuan Laboratory, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University, Guangzhou 510632, China. thlt@jnu.edu.cn.
⁸ Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices, South China University of Technology, Guangzhou 510640, China. hbwu@scut.ed.cn.
⁹ Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices, South China University of Technology, Guangzhou 510640, China. xuwei@scut.ed.cn.
¹⁰ Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices, South China University of Technology, Guangzhou 510640, China. pswbh@scut.ed.cn.

Abstract

We propose Sb-doped TiO₂ as electron acceptor material for depleted CdTe nanocrystal (NC) hetero-junction solar cells. Novel devices with the architecture of FTO/ZnO/Sb:TiO₂/CdTe/Au based on CdTe NC and TiO₂ precursor are fabricated by rational ambient solution process. By introducing TiO₂ with dopant concentration, we are able to tailor the optoelectronic properties of NC solar cells. Our novel devices demonstrate a very high open circuit voltage of 0.74 V, which is the highest V_oc reported for any CdTe NC based solar cells. The power conversion efficiency (PCE) of solar cells increases with the increase of Sb-doped content from 1% to 3%, then decreases almost linearly with further increase of Sb content due to the recombination effect. The champion device shows J_sc, V_oc, FF, and PCE of 14.65 mA/cm², 0.70 V, 34.44, and 3.53% respectively, which is prospective for solution processed NC solar cells with high V_oc.

Keywords: CdTe; heterojunction; nanocrystal; solar cells.