Thermally Activated in Situ Doping Enables Solid-State Processing of Conducting Polymers

Abstract

Free-standing bulk structures encompassing highly doped conjugated polymers are currently heavily explored for wearable electronics as thermoelectric elements, conducting fibers, and a plethora of sensory devices. One-step manufacturing of such bulk structures is challenging because the interaction of dopants with conjugated polymers results in poor solution and solid-state processability, whereas doping of thick conjugated polymer structures after processing suffers from diffusion-limited transport of the dopant. Here, we introduce the concept of thermally activated latent dopants for in situ bulk doping of conjugated polymers. Latent dopants allow for noninteractive coprocessing of dopants and polymers, while thermal activation eliminates any thickness-dependent diffusion and activation limitations. Two latent acid dopants were synthesized in the form of thermal acid generators based on aryl sulfonic acids and an o-nitrobenzyl capping moiety. First, we show that these acid dopant precursors can be coprocessed noninteractively with three different polythiophenes. Second, the polymer films were doped in situ through thermal activation of the dopants. Ultimately, we demonstrate that solid-state processing with a latent acid dopant can be readily carried out and that it is possible to dope more than 100 μm-thick polymer films through thermal activation of the latent dopant.

Tuning of the elastic modulus of a soft polythiophene through molecular doping

“…Molecular doping of stiff conjugated polymers does not tend to strongly alter their mechanical properties (Table 1). [7][8][9] As a result, doping is typically not considered as a tool that allows to adjust the elastic modulus of conjugated polymers.…”

“…a low figure of merit of Z E À0.4 (Table 1). 8 Further, a diketopyrrolopyrrole (DPP) based copolymer (E = 374 MPa) 12 displayed a reduction in T g from 55 to 27 1C upon doping with 1 wt% of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) (see Fig. 1 for chemical structure), resulting in a more stretchable material as evidenced by a higher crack onset strain.…”

Three-Dimensional Finite Element Numerical Simulation and Analysis of Solid-State Processing of Metal Material

“…Stress and strain field analysis is the basis for optimizing the rolling process. e key to accurate simulation is the establishment of solid material models and the optimization of simulation parameters, and the 3D simulation has further increased the difficulty [6].…”

Thermally Activated n‐Doping of Organic Semiconductors Achieved by N‐Heterocyclic Carbene Based Dopant

“…In most cases, the n‐doped organic semiconductor devices were prepared in an inert atmosphere, increasing the complexity of device fabrications. The n‐doping by thermally activated dopants involves a two‐step process, deposition and post‐deposition annealing [15] . Given the excellent air stability and non‐interaction with semiconductors before heating, DMImC can be noninteractively sequentially deposited onto FBDPPV films in air.…”