Dibenzothiophene sulfone-based n-type emissive organic semiconductor

Developing high-mobility emissive organic semiconductors (OSCs) is crucial for organic light-emitting transistors (OLETs), which belong to a type of the smallest integrated optoelectronic devices, with great potential in next-generation display technologies. Although p-type high-mobility emissive OSCs have achieved considerable progress, n-type OSC materials have rarely been reported. Herein, we designed and synthesized an n-type dibenzothiophene sulfone-based emissive organic semiconductor of DPIDBSO with photoluminescence quantum yields (PLQYs) of 30% in the solid state. Interestingly, it was found that in the DPIDBSO crystal, the growth direction was along the short axis of the molecule rather than along the π-π stacking direction owing to multiple weak hydrogen bonds and the presence of a crystal growth dead zone. Leveraging this “special” crystal, DPIDBSO demonstrated typical n-type transport with an electron mobility of 0.17 cm² V⁻¹ s⁻¹. More importantly, DPIDBSO-based devices with only Ag electrodes showed obvious electroluminescence with an immobile emission zone in the unipolar mode. This work provides deep insights into the development of n-type OSCs with tunable optoelectronic properties through the control of the aggregation state towards high-performance OLETs.