# Step towards High Power Factor in Acidic-Doped Poly(3-hexylthiophene) Systems

## TL;DR

This study shows that dodecylbenzenesulfonic acid (DBSA) can effectively dope P3HT, achieving high thermoelectric performance comparable to other common dopants.

## Contribution

DBSA is introduced as a cost-effective and less toxic alternative to F4TCNQ for doping P3HT with improved thermoelectric properties.

## Key findings

- DBSA doping achieved a power factor of 2.706 μW·m⁻¹·K⁻² at 11% v/v concentration.
- Higher DBSA concentrations reduced surface roughness and influenced conductivity.
- Thermoelectric parameters were comparable to sulfuric acid and F4TCNQ-doped P3HT.

## Abstract

In this study, we present dodecylbenzenesulfonic acid
(DBSA) as
a cost-effective alternative to F4TCNQ for doping poly­(3-hexylthiophene)
(P3HT). DBSA not only acts as a p-type dopant but also serves as a
surfactant, influencing the material’s morphology and electronic
properties. We investigated the impact of dopant concentration (ranging
from 0.0001% to 20% v/v) on electrical conductivity, Seebeck coefficient,
and power factor in spin-coated thin films. Seebeck coefficient values
ranged from 59 μV·K–1 (at 12% v/v DBSA)
to 352.9 μV·K–1 (at 0.1% v/v DBSA), while
the optimal P3HT:DBSA composition (11% v/v DBSA) exhibited a conductivity
of 5.58 S·cm–1, a Seebeck coefficient of 69.7
μV·K–1, and a power factor of 2.706 μW·m–1·K–2. Atomic force microscopy
(AFM) revealed that higher DBSA concentrations reduced surface roughness,
influencing the conductivity. The obtained thermoelectric parameters
are comparable to those of sulfuric acid and F4TCNQ-doped P3HT, highlighting
DBSA as a promising and less toxic alternative for organic thermoelectrics.