Characterization of aryl-functionalized 2,4,6-tris(2-thienyl)-1,3,5-triazine thin films and their application to organic field-effect transistors

Abstract

Aryl-functionalized 2,4,6-tris(2-thienyl)-1,3,5-triazine derivatives were applied as thin films via thermal vacuum deposition to investigate properties and potential of the thin films for use as active layers in organic field-effect transistors. All derivatives deposited on quartz substrates produced amorphous films. Ultraviolet–visible absorption spectra of the films resemble those of the molecules in solution, and fluorescence spectra depend largely on the aryl groups. When used in organic field-effect transistors, only the N,N-dibutylamino derivative could display the appropriate device characteristics under p-type operation, but it showed low mobility of charge carriers. The origin of the low mobility is discussed in terms of the electronic structure and film structure of the derivatives in the devices.

Advances in the Chemistry of 2,4,6‐Tri(thiophen‐2‐yl)‐1,3,5‐triazine

“…The incorporation of thienyltriazine in material chemistry leads to compounds with narrow energy gap (band gap) which means the structural and optical properties of the resulting materials can be easily tuned by tuning the extent of conjugation of the groups present. [27] Also, molecules with strong pull-push effect (donor-acceptor) and good coplanarity enhance the flow of electrons and/or holes and also facilitate exciton separation. Large number of heteroatoms also widen the possibility of interaction with guest molecules.…”

“…Both the thiophene and triazine units can lead to different types of interaction in the resulting compounds. [27] Presence of thiophene has been known to enhance intra-and intermolecular interactions such as Vander Waals interaction, π-π stacking, weak hydrogen bonds, S•••S interactions arising due to the high polarizability of the presence of sulfur. [28][29][30] As discussed previously, triazine unit enhances the existence of supramolecular interactions.…”

“…This molecule possesses unique features such as a π‐electron deficient core that is 1,3,5‐triazine, three thiophene as π‐electron rich side branch, highly symmetrical and coplanar structure ( C 3h symmetry), possibility of easy functionalization of α‐positions of thiophene for further extension of conjugation etc. Both the thiophene and triazine units can lead to different types of interaction in the resulting compounds [27] . Presence of thiophene has been known to enhance intra‐ and intermolecular interactions such as Vander Waals interaction, π‐π stacking, weak hydrogen bonds, S ⋅⋅⋅ S interactions arising due to the high polarizability of the presence of sulfur [28–30] .…”

“…As discussed previously, triazine unit enhances the existence of supramolecular interactions. The incorporation of thienyltriazine in material chemistry leads to compounds with narrow energy gap (band gap) which means the structural and optical properties of the resulting materials can be easily tuned by tuning the extent of conjugation of the groups present [27] …”

Synthetic Bilayers on Mica from Self-Assembly of Hydrogen-Bonded Triazines

“…Preparing molecularly ordered thin films during solution processing can improve the performance of thin-film organic semiconductors and organic light-emitting diodes (OLED) . Controlled deposition of crystalline thin films for electronic applications can inhibit hole carrier mobility and trap-free charge transport . Molecular crystallization with precise layer definition has been achieved to produce single-crystal semiconductors from benzothiophene derivatives, fused benzoacridines, and hydrogen-bonded naphthalenediimide semiconductors .…”