Switchable Charge Injection Barrier in an Organic Supramolecular Semiconductor
2016 (English)In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 8, no 24, 15535-15542 p.Article in journal (Refereed) PublishedText
We disclose a supramolecular material that combines semiconducting and dipolar functionalities. The material consists of a discotic semiconducting carbonyl-bridged triarylamine core, which is surrounded by three dipolar amide groups. In thin films, the material self-organizes in a hexagonal columnar fashion through Jr-stacking of the molecular core and hydrogen bonding between the amide groups. Alignment by an electrical field in a simple metal/semiconductor/metal geometry induces a polar order in the interface layers near the metal contacts that can be reversibly switched, while the bulk material remains nonpolarized. On suitably chosen electrodes, the presence of an interfacial polarization field leads to a modulation of the barrier for charge injection into the semiconductor. Consequently, a reversible switching is possible between a high-resistance, injection-limited off-state and a low-resistance, space-charge-limited on-state. The resulting memory diode shows switchable rectification with on/off ratios of up to two orders of magnitude. This demonstrated multifunctionality of a single material is a promising concept toward possible application in lowcost, large-area, nonvolatile organic memories.
Place, publisher, year, edition, pages
AMER CHEMICAL SOC , 2016. Vol. 8, no 24, 15535-15542 p.
organic semiconductors; current switching; memories; polarization; rectification; dipolar switching; injection barrier
IdentifiersURN: urn:nbn:se:liu:diva-130278DOI: 10.1021/acsami.6b02988ISI: 000378584800072PubMedID: 27246280OAI: oai:DiVA.org:liu-130278DiVA: diva2:950602
Funding Agencies|NWO Nano program; Bavarian State Ministry of Science, Research, and the Arts for the Collaborative Research Network Solar Technologies go Hybrid; Deutsche Forschungsgemeinschaft (DFG) [SFB 953]; Vetenskapsradet [2015-03813]2016-08-012016-07-282016-08-24