Abstract A series of alkyl substituted 9,9′-bianthracene derivatives (BAs) with easy availability and low cost have been applied as deep-blue emitters and blue host materials in fluorescent organic light-emitting diodes (OLEDs). The nearly perpendicular geometry configuration of 9,9′-bianthracene and the additional alkyl units with large steric hindrance in methyl substituted MBA and tert- butyl substituted TBBA would reduce the aggregation formation emitting at longer wavelength by intramolecular and intermolecular interaction, which endows both of the compounds with good thermal properties, and film-forming abilities as well as excellent electroluminescence performance. Nondoped pure deep-blue OLED using TBBA as the emitter showed good performance with EQE of 3.20% and high color purity with CIE (0.15, 0.06), which matched the EBU standard blue very well. Furthermore, these BAs worked as excellent host materials for p -bis(p - N,N -diphenyl-aminostyryl)benzene (DSAph) dopant to get high-performance OLEDs with low turn-on voltages and high efficiencies, especially for MBA bearing two methyl substituents at 3- and 3′-positions of the 9,9′-bianthracene as the fluorescent host with a low turn-on voltage of 3.0 V, a high current efficiency of 16.54 cd/A and a high EQE of 9.47% with unobservable efficiency roll-off. Particularly, EQE can be maintained over 9.20% with very little variation of 0.54% in the range of luminance value of 1.54–13800 cd/m2 for the MBA-based device. The improved EQEs are due to the enhanced occurrence of singlet excitons in BAs-based devices. Graphical abstract Image 1 Highlights • Alkyl substituted 9,9'-bianthracene derivatives (BAs) with easy availability and low cost. • Nondoped TBBA-based blue OLED showed EQE of 3.20% with excellent CIE (0.15, 0.06). • EQE maintained over 9.24% with very little variation of 0.54% in the range of luminance 1.54–13800 cd/m2 for MBA:DSAph-based device. [ABSTRACT FROM AUTHOR]