Effectively modulating thermal activated charge transport in organic semiconductors by precise potential barrier engineering

Abstract

The temperature dependence of charge transport dramatically affects and even determines the properties and applications of organic semiconductors, but is challenging to effectively modulate. Here, we develop a strategy to circumvent this challenge through precisely tuning the effective height of the potential barrier of the grain boundary (i.e., potential barrier engineering). This strategy shows that the charge transport exhibits strong temperature dependence when effective potential barrier height reaches maximum at a grain size near to twice the Debye length, and that larger or smaller grain sizes both reduce effective potential barrier height, rendering devices relatively thermostable. Significantly, through this strategy a traditional thermo-stable organic semiconductor (dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene, DNTT) achieves a high thermo-sensitivity (relative current change) of 155, which is far larger than what is expected from a standard thermally-activated carrier transport. As demonstrations, we show that thermo-sensitive OFETs perform as highly sensitive temperature sensors.

Identifying Key Transport Mechanisms in Organic Antiambipolar Transistors

“…Both the DNTT and PTCDI-C13 devices showed |V T | increasing with decreasing T, in line with the reported trends. [23][24][25] When comparing the two OFETs, the V T shift of the DNTT device was slightly larger that of the PTCDI-C13 counterpart. In this case, the overall stronger positive shift (with increasing T) of www.advelectronicmat.de the DNTT V T can force the V peak of the AAT to move in the same direction, even though the PTCDI channel is providing a weaker counteracting negative V T shift.…”

Multiplexed Neurotransmission Emulated by a p–n Cross Nanowire Synaptic Transistor for Satiety, Depression, and Drug Withdrawal

“…In contrast, trapped ions in n-NWs are relatively difficult to get back to ion gel due to the energy barrier as provided by p-NWs in between n-NWs and ion gel to extend the doping effect. [23][24][25] These phenomena are similar to the plasticity of brain synapses, which is involved in learning, memory, and emotion regulation. Decrease in the plasticity of nerve cells can cause damage to brain structures, which in turn can lead to emotional dysregulation and defects in cognitive and memory functions, which ultimately lead to depression (Figure 4c).…”

Well-balanced ambipolar diketopyrrolopyrrole-based copolymers for OFETs, inverters and frequency doublers

“…Untill now, conjugated polymers with easily tuned optoelectronic properties have shown great applications in various fields, including organic field-effect transistors (OFETs) [5][6][7], organic light-emitting diodes (OLEDs) [8][9][10] and organic photovoltaic cells (OPVs) [11][12][13][14][15]. Particularly, OFETs as electrical switches are the most significant component for organic circuits and other related organic integrated (opto) electronic devices [16][17][18][19][20][21][22][23][24][25]. According to the difference of the majority charge carriers, OFETs can be classified into unipolar p-channel (hole-only) or n-channel (electron-only) and ambipolar (hole and electron) devices.…”