Benzoyl Peroxide as an Efficient Dopant for Spiro-OMeTAD in Perovskite Solar Cells

4 years ago

Benzoyl Peroxide as an Efficient Dopant for Spiro-OMeTAD in Perovskite Solar Cells

Tongyi Zhang, Qingyong Tian, Hua Bai, Baozeng Wang, An'an Zhou, Bin Fan, Qin'e Zhang, Lisheng Fan, Qiuju Liu

Although organic small molecule spiro-OMeTAD is widely used as a hole-transport material in perovskite solar cells, its limited electric conductivity poses a bottleneck in the efficiency improvement of perovskite solar cells. Here, a low-cost and easy-fabrication technique is developed to enhance the conductivity and hole-extraction ability of spiro-OMeTAD by doping it with commercially available benzoyl peroxide (BPO). The experimental results show that the conductivity increases several orders of magnitude, from 6.2×10−6 S cm−1 for the pristine spiro-OMeTAD to 1.1×10−3 S cm−1 at 5 % BPO doping and to 2.4×10−2 S cm−1 at 15 % BPO doping, which considerably outperform the conductivity of 4.62×10−4 S cm−1 for the currently used oxygen-doped spiro-OMeTAD. The fluorescence spectra suggest that the BPO-doped spiro-OMeTAD–OMeTAD layer is able to efficiently extract holes from CH3NH3PbI3 and thus greatly enhances the charge transfer. The BPO-doped spiro-OMeTAD is used in the fabrication of perovskite solar cells, which exhibit enhancement in the power conversion efficiency. That′s so dope! A low-cost and easy-fabrication technique is developed to enhance the conductivity and holeextraction ability of spiro-OMeTAD by doping it with commercially available benzoyl peroxide (BPO). The BPO-doped spiro-OMeTAD layer shows high conductivity and is an efficient hole-extraction material for CH3NH3PbI3, thus greatly enhancing the charge transfer and the power conversion efficiency of the device.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/cssc.201700872