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DOE OSTI · 2555701

On-Surface Reactions of Electronically Active Self-Assembled Monolayers for Electrode Work Function Tuning

Ruvalcaba, Ricardo [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)]·Liu, Zhongzhe [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)]·Nugraha, Mohamad Insan [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia); National Research and Innovation Agency (BRIN) (Indonesia)] (ORCID:0000000193521902)·Harrison, George [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)]·Yang, Yu-Ying [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)] (ORCID:0009000243311418)·Thaler, Marco [Univ. Innsbruck (Austria)]·Marsh, Adam V. [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)]·Zeilerbauer, Matthias [Univ. Innsbruck (Austria)]·Aivalioti, Chrysa [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)]·Aguileta-Vazquez, Raul Ricardo [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)]·Tsetseris, Leonidas [National Technical University of Athens (Greece)]·Patera, Laerte L. [Univ. Innsbruck (Austria)] (ORCID:0000000262145681)·Zahl, Percy [Brookhaven National Laboratory (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)] (ORCID:0000000266297500)·Heeney, Martin [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)]·Anthopoulos, Thomas D. [Univ. of Manchester (United Kingdom)] (ORCID:0000000209788813)·Fatayer, Shadi [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)] (ORCID:0000000342603208)
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Abstract

Self-assembled monolayers (SAMs) help improve the performance of organic electronic devices through interface passivation and enhanced carrier transport. Yet, there is limited information regarding the chemical structure of the SAMs upon functionalization and subsequent thermal treatment. Here, we studied the on-surface reaction of carbazole-derived SAMs on model gold electrodes, focusing on the chemical structure changes induced by thermal treatments. Furthermore, we correlate the microscopic changes with their impact on the electrode’s work function. The carbazole-based SAMs first transform into organometallic complexes. At higher annealing temperatures, SAMs convert to oligomeric complexes. The observed chemical reactions significantly reduce the electrode work function and facilitate electron injection in n-type organic thin-film transistors. Our results highlight the on-surface synthesis of electronically active SAMs as an alternative approach for modifying the work function of electrodes for organic electronics.

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Ruvalcaba, Ricardo [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)], Liu, Zhongzhe [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)], Nugraha, Mohamad Insan [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia); National Research and Innovation Agency (BRIN) (Indonesia)] (ORCID:0000000193521902), Harrison, George [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)], Yang, Yu-Ying [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)] (ORCID:0009000243311418), Thaler, Marco [Univ. Innsbruck (Austria)], Marsh, Adam V. [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)], Zeilerbauer, Matthias [Univ. Innsbruck (Austria)], Aivalioti, Chrysa [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)], Aguileta-Vazquez, Raul Ricardo [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)], Tsetseris, Leonidas [National Technical University of Athens (Greece)], Patera, Laerte L. [Univ. Innsbruck (Austria)] (ORCID:0000000262145681), Zahl, Percy [Brookhaven National Laboratory (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)] (ORCID:0000000266297500), Heeney, Martin [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)], Anthopoulos, Thomas D. [Univ. of Manchester (United Kingdom)] (ORCID:0000000209788813), Fatayer, Shadi [King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)] (ORCID:0000000342603208). 2025-03-19. On-Surface Reactions of Electronically Active Self-Assembled Monolayers for Electrode Work Function Tuning. https://doi.org/10.1021/acsmaterialslett.4c02267

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