9,9-Bis[4-[(4-ethenylphenyl)methoxy]phenyl]-N²,N⁷-di-1-naphthalenyl-N²,N⁷-diphenyl-9H-Fluorene-2,7-diamine

9,9-Bis[4-[(4-ethenylphenyl)methoxy]phenyl]-N²,N⁷-di-1-naphthalenyl-N²,N⁷-diphenyl-9H-Fluorene-2,7-diamine, also known as VB-FNPD, is a solution-processable crosslinkable Hole Transport / Hole Injection Layer (HTL / HIL) material popularly used in optoelectronic devices, such as quantum-dot light-emitting diodes (QD-LEDs) [1], and perovskite light-emitting diodes (PeLEDs) [2,3].For instance, it was shown that thermally crosslinkable VB-FNPD is a great candidate for the HTL of QD-LEDs [1]. Device with VB-FNPD HTL crosslinking at 170 °C has the highest luminance of 7702 cd/m², the maximum c.d. (J) of 41.98 mA/cm², the maximum current efficiency (CE) of 5.45 Cd/A, and the maximum external quantum efficiency (EQE) of 1.64%.VB-FNPD was also successfully used as hole-transporting material in PeLEDs to to improve the hole-injection efficiency of PeLEDs [2,3].