Unsubstituted thiophene–diketopyrrolopyrrole conjugated polymer thin films via oxidative chemical vapor deposition – electronic behavior

Abstract

Conjugated polymers (CPs) based on diketopyrrolopyrrole (DPP) constitue an important class of high-performance organic semiconductors. While N-alkylation of DPP is required for the solution-based synthesis of DPP-based CPs, oxidative chemical...

Ultrafast electron dynamics in excited states of conjugated thiophene–fluorene organic polymer (pF8T2) thin films

“…Similar observations of a non-existent or only weak effect on the dynamics of the excitonic states by different pre-treatments or post-treatments, such as annealing, have been reported before for conjugated polymers. 44,79–82…”

Chemical vapor deposition of high charge carrier mobility benzothiadiazole-based conjugated polymer thin films

“…4,7-dithien-2-yl-2,1,3-benzothiadiazole (DTBT), was obtained using a previously reported Stille coupling procedure. 11,13 The oCVD reaction of DTBT with iron( iii ) chloride (FeCl 3 ), selected due to its ability to promote the dehydrogenative coupling of thienyl-substituted compounds, 29,34 was carried out under vacuum (10 −3 mbar) in a custom-built oCVD reactor (Scheme S1, ESI†). 41 Briefly, DTBT and FeCl 3 were concomitantly sublimed towards a heated substrate holder (100 °C) using two low temperature evaporators.…”

“…Interestingly, the absence of solubilizing groups allows reducing the intermolecular distances in conjugated polymer thin films, which can yield superior charge carrier density and mobility, improved delocalization and electrical conductivities. 31–33 Such a feature was previously exploited to increase the lifetime of electronically excited states, 34 and enhance the sensing 35 and catalytic properties 36 of conjugated polymer thin films prepared via the oCVD of polycyclic aromatic compounds. Upon reaction with a suitable oxidizing agent, 29,37–39 both simple electron-rich monoaromatic compounds 30,32,38,40 and polycyclic aromatic compounds 31,34–36,39 can be polymerized via oCVD.…”

“…31–33 Such a feature was previously exploited to increase the lifetime of electronically excited states, 34 and enhance the sensing 35 and catalytic properties 36 of conjugated polymer thin films prepared via the oCVD of polycyclic aromatic compounds. Upon reaction with a suitable oxidizing agent, 29,37–39 both simple electron-rich monoaromatic compounds 30,32,38,40 and polycyclic aromatic compounds 31,34–36,39 can be polymerized via oCVD. A recent report has demonstrated that conjugated polymer thin films can even be grown from electron-poor aromatic compounds, e.g.…”

“…A recent report has demonstrated that conjugated polymer thin films can even be grown from electron-poor aromatic compounds, e.g. diketopyrrolopyrrole, 34 provided that they are functionalized with electron-rich groups that provide active sites enabling intermolecular oxidative polymerization. In this work, we report for the first time the preparation of benzothiadiazole–oligothiophene D–A conjugated polymer thin films using oCVD.…”