TY - JOUR
T1 - Microstructural control suppresses thermal activation of electron transport at room temperature in polymer transistors
AU - Luzio, Alessandro
AU - Nübling, Fritz
AU - Martin, Jaime
AU - Fazzi, Daniele
AU - Selter, Philipp
AU - Gann, Eliot
AU - McNeill, Christopher R.
AU - Brinkmann, Martin
AU - Hansen, Michael Ryan
AU - Stingelin, Natalie
AU - Sommer, Michael
AU - Caironi, Mario
PY - 2019/7/29
Y1 - 2019/7/29
N2 - Recent demonstrations of inverted thermal activation of charge mobility in polymer field-effect transistors have excited the interest in transport regimes not limited by thermal barriers. However, rationalization of the limiting factors to access such regimes is still lacking. An improved understanding in this area is critical for development of new materials, establishing processing guidelines, and broadening of the range of applications. Here we show that precise processing of a diketopyrrolopyrrole-tetrafluorobenzene-based electron transporting copolymer results in single crystal-like and voltage-independent mobility with vanishing activation energy above 280 K. Key factors are uniaxial chain alignment and thermal annealing at temperatures within the melting endotherm of films. Experimental and computational evidences converge toward a picture of electrons being delocalized within crystalline domains of increased size. Residual energy barriers introduced by disordered regions are bypassed in the direction of molecular alignment by a more efficient interconnection of the ordered domains following the annealing process.
AB - Recent demonstrations of inverted thermal activation of charge mobility in polymer field-effect transistors have excited the interest in transport regimes not limited by thermal barriers. However, rationalization of the limiting factors to access such regimes is still lacking. An improved understanding in this area is critical for development of new materials, establishing processing guidelines, and broadening of the range of applications. Here we show that precise processing of a diketopyrrolopyrrole-tetrafluorobenzene-based electron transporting copolymer results in single crystal-like and voltage-independent mobility with vanishing activation energy above 280 K. Key factors are uniaxial chain alignment and thermal annealing at temperatures within the melting endotherm of films. Experimental and computational evidences converge toward a picture of electrons being delocalized within crystalline domains of increased size. Residual energy barriers introduced by disordered regions are bypassed in the direction of molecular alignment by a more efficient interconnection of the ordered domains following the annealing process.
UR - http://www.scopus.com/inward/record.url?scp=85069942484&partnerID=8YFLogxK
U2 - 10.1038/s41467-019-11125-9
DO - 10.1038/s41467-019-11125-9
M3 - Article
C2 - 31358747
AN - SCOPUS:85069942484
VL - 10
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
IS - 1
M1 - 3365
ER -