A Simple and Effective Phosphine-Doping Technique for Solution-Processed Nanocrystal Solar Cells

Chenbo Min; Yihui Chen; Yonglin Yang; Hongzhao Wu; Bailin Guo; Sirui Wu; Qichuan Huang; Donghuan Qin; Lintao Hou

doi:10.3390/nano13111766

A Simple and Effective Phosphine-Doping Technique for Solution-Processed Nanocrystal Solar Cells

Nanomaterials (Basel). 2023 May 30;13(11):1766. doi: 10.3390/nano13111766.

Authors

Chenbo Min¹, Yihui Chen¹, Yonglin Yang¹, Hongzhao Wu¹, Bailin Guo¹, Sirui Wu¹, Qichuan Huang¹, Donghuan Qin^{1

2}, Lintao Hou³

Affiliations

¹ School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
² State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China.
³ Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Siyuan Laboratory, Department of Physics, Jinan University, Guangzhou 510632, China.

Abstract

Solution-processed cadmium telluride (CdTe) nanocrystal (NC) solar cells offer the advantages of low cost, low consumption of materials and large-scale production via a roll-to-roll manufacture process. Undecorated CdTe NC solar cells, however, tend to show inferior performance due to the abundant crystal boundaries within the active CdTe NC layer. The introduction of hole transport layer (HTL) is effective for promoting the performance of CdTe NC solar cells. Although high-performance CdTe NC solar cells have been realized by adopting organic HTLs, the contact resistance between active layer and the electrode is still a large problem due to the parasitic resistance of HTLs. Here, we developed a simple phosphine-doping technique via a solution process under ambient conditions using triphenylphosphine (TPP) as a phosphine source. This doping technique effectively promoted the power conversion efficiency (PCE) of devices to 5.41% and enabled the device to have extraordinary stability, showing a superior performance compared with the control device. Characterizations suggested that the introduction of the phosphine dopant led to higher carrier concentration, hole mobility and a longer lifetime of the carriers. Our work presents a new and simple phosphine-doping strategy for further improving the performance of CdTe NC solar cells.

Keywords: cadmium telluride nanocrystals; phosphine-doping technique; photovoltaic device.

Grants and funding

We thank the financial support of the National Natural Science Foundation of China (Nos. 91333206, 61774077, 61274062, 21174042 and 11204106), National Science Foundation for Distinguished Young Scholars of China (Grant no. 51225301), Key Projects of Joint Fund of Basic and Applied Basic Research Fund of Guangdong Province (2019B1515120073, 2019B090921002), the Guangzhou Science and Technology Plan Project and the Fundamental Research Funds for the Central Universities.