Effect of incorporation of black phosphorus into PEDOT:PSS on conductivity and electron–phonon coupling

• Black phosphorus (BP) is a p-type two-dimensional material.
• The doping mechanism for BP-doped PEDOT:PSS samples is investigated.
• The domination of tunneling (hopping) at low (high) temperatures is observed.
• BP doping leads to an increase in conductivity of PEDOT:PSS.
• The increased conductivity is due to the reduced electron-phonon coupling.

The effect of incorporation of few-layer black phosphorus (BP) into poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) on conductivity is investigated. BP is a two-dimensional material with high carrier mobility. It is shown that the carrier mobility (μ) increases significantly while the carrier density does not change substantially at 300 K. μ in PEDOT:PSS samples with or without BP addition exhibits a strong temperature dependence, which demonstrates the dominance of tunneling (hopping) at low (high) temperatures. The high conductivity of PEDOT:PSS samples with the addition of BP is attributed to the arrangement of the high hole-mobility BP sheets that induces the modification of the electron-phonon coupling.