N2,N2',N7,N7'-tetrakis(2,4-dimethoxyphenyl)-N2,N2',N7,N7'-tetraphenyl- 9,9'-spirobi[fluorene]-2,2',7,7'-tetraamine

High-mobility organic semiconductor hole transport material (HTM) for use in electron transport layer in sensors, OPV and OLED applications. Derivatives of spiro-OMeTAD have been widely studied because of their outstanding performance. It was demonstrated th at 2,4-spiro-OMeTAD as HTM in photovoltaic cells shows excelent stability and power conversion efficiency in perovskite solar cells. Zhang et al reported a power conversion efficiency of 17.2% and solar cell filling factor of 70.1% when using 2,4-spiro-OMeTAD.', 'Spiro-MeOTAD can be used as a hole transport material in perovskite solar cells and solid-state dye-sensitized solar cells (DSSCs) as it helps to efficiently extract and transport positive charges (holes) from the perovskite layer to the electrode, improving the overall device performance and stability. It can be used as a hole injection and transport material in OLEDs, especially in small molecule-based and solution-processed OLEDs.