Fabrication of thermally conductive boron nitride nanosheets-conjugated poly(3-hexylthiophene) composite with enhanced photothermal property.

• Observation of enhanced photothermal performance of BNNS-P3HT composite film. • Increased in-plane thermal conductivity of BNNS-P3HT composite film by hot-pressing. • Cytotoxicity test of such composite film shows prospect in photothermal biosystems. This paper presents a study on the impact of π-π stacking interaction on the thermal and photothermal performance of boron nitride nanosheets (BNNS)-conjugated poly(3-hexylthiophene) (P3HT) composite. The composite shows improved thermal conductivity of 4.40 Wm−1K−1 at 30 wt% BNNS loading, which enhances 511 % relative to the pure P3HT film. Furthermore, with the assistance of hot-pressing approach, its thermal conductivity could be increased to 5.19 Wm−1K−1 at the same loading. Additionally, the composite exhibits excellent photothermal property that the surface temperature of BNNS-P3HT can rise to ∼98.3 °C after 120 s under 808 nm laser light irradiation with power density of 1.31 W/cm2. [ABSTRACT FROM AUTHOR]