A mixed hole transport material employing a highly planar conjugated molecule for efficient and stable perovskite solar cells. Issue 10 (25th February 2020)

• Record Type: Journal Article
• Authors: Ji, Xiaofei; Zhou, Tong; Ke, Xin; Wang, Wenxuan; Wu, Shanyu; Zhang, Mingtao; Lu, Di; Zhang, Xiaodan; Liu, Yongsheng
• Is Part Of: Journal of materials chemistry. Volume 8:Issue 10(2020)
• Page Start: 5163
• Page End: 5170
• Publication Date: 2020-02-25
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9ta13365h
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : An efficiency of 21.31% was achieved with enhanced stability for a mixed HTM-based device because of the high hole mobility, low reorganization energy and surface passivate effect of the DRSBDT-2OT component. Abstract : We successfully demonstrated a simple and facile way to improve the efficiency and stability of perovskite solar cells using a mixed hole transport material, which was a composite of spiro-OMeTAD and a conjugated small molecule, DRSBDT-2OT. DRSBDT-2OT, with an acceptor–donor–acceptor (A–D–A) structure, exhibits a high molecular planarity via noncovalent intramolecular S⋯O interactions, leading to comparatively low reorganization energy and high hole mobility. Owing to the surface passivation effects of DRSBDT-2OT in the mixed HTM and the increased hole mobility in comparison with the spiro-OMeTAD, the mixed HTM-based device exhibits a significantly enhanced efficiency of 21.31%, which is much higher than that of single-component HTM-based devices. Furthermore, the mixed HTM-based devices are much more stable than the control devices that use Sprio-OMeTAD as the HTM. These findings pave the way for the rational design of planar hole-transport materials for mixed HTMs toward efficient and stable perovskite solar cells.