题目：

A 12%-Efficient Upgraded Metallurgical Grade SiliconOrganic Heterojunction Solar Cell Achieved by a Self-Purifying Process

作者：

Jie Zhang, Tao Song, Xinlei Shen, Xuegong Yu, Shuit-Tong Lee, and Baoquan Sun

单位：

Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, 199 Ren’ai Road, Suzhou, Jiangsu 215123, PR China

摘要：

Low quality silicon such as upgraded metallurgical-grade (UMG) silicon promises to reduce the material requirements for high-performance cost-effective photovoltaics. So far, however, UMG silicon currently exhibits the short diffusion length and large charge recombination associated with high impurity level, which hinders the performance of solar cell. Here, we used a metal-assisted chemical etching (MACE) method to partially upgrade the UMG silicon surface. The silicon was etched into nanostructured one by the MACE process associated with removing impurity on the surface. Meanwhile, nanostructured forms of UMG silicon can benefit the improved light harvesting with thin substrate, which can relax the requirement of materials purity for high performance. In order to suppress the large surface recombination due to increased surface area of nanostructured UMG silicon, a post chemical treatment was used to decrease surface area. A solution processed conjugated polymer of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) was deposited on UMG silicon at low temperature (<150 oC) to form heterojunction for avoiding any impurity diffusion in the silicon substrate. By optimizing the thickness of silicon and suppressing the charge recombination at the interface between thin UMG silicon/PEDOT:PSS, we are able to achieve 12.0%-efficient organic-inorganic hybrid solar cells, which are higher than those analogous UMG silicon devices. We show that the modified UMG silicon surface can increase the minority carrier lifetime because of reduced impurity and surface area. Our results suggest designed rule for efficient silicon solar cell with low quality silicon absorbers.

影响因子：

12.033

分区情况：

1区

链接：

http://pubs.acs.org/doi/abs/10.1021/nn504279d