Tuning the Performance of PSCs Using the Effective Organic Molecular Hole-transporting Materials:A Review

Xiu-wen ZouPiao GuoYing-ying ZhouYi-ming LuoYuan-yuan Li^*Qi-Yuan Yang^*

• Nanning Normal University, Guangxi Key Laboratory of Natural Polymer Chemistry and Physics, Nanning, China

Abstract: This review article discusses the current designs and synthetic procedures for organic small molecules as hole-transporting materials (HTMs) with a focus on their structure–property correlation, short circuit current density (Jsc), open-circuit voltage (Voc),fill factor (FF) and power conversion efficiency (PCE), as well as their material optimization. While optimizing non-planar spiro like compounds, various conjugated aromatic, planar molecules, and even porphyrin metal complexes are being developed have been studied as being important for the generation of new HTMs. Heteroatoms such as oxygen, sulfur, nitrogen, silicon, and selenium have been proven to be beneficial for the development of more stable and cost-effective HTMs and perovskite solar cells (PSCs), developing a new organic molecular to be HTMs or HTMs-dopant would be a viable approach for PSCs. A deeper understanding of the organic small molecular perovskite/HTMs can also provide insight into the design of novel molecular architectures capable of achieving effective and stable PSCs systems. Finally, an outlook is presented for the further development of conventional PSCs with organic molecular HTMs.