A PEDOT:PSS nanocomposite film doped with black phosphorus modified with silver nanoparticles for wearable photothermoelectric generators

Photothermoelectric (PTE) materials have gained significant attention as a promising avenue for converting light into electricity. Herein, the PTE properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) are enhanced by introducing black phosphorus nanosheets (BP NSs) modified with silver nanoparticles (Ag@BP). Under 100 mW cm−2 illumination, the resulting PEDOT:PSS/Ag@BP nanocomposite film (P_Ag@BP) exhibits an output voltage of 528.4 μV compared to 300.9 μV for the PEDOT:PSS film. This is attributed to (i) the enhanced photothermal performance of P_Ag@BP, which generates a temperature difference of 18 °C under 100 mW cm−2 illumination compared to 10 °C for the PEDOT:PSS film and (ii) the enhanced thermoelectric performance of P_Ag@BP, with an increased power factor of 107.2 μW m−1 K−2 compared to 32.9 μW m−1 K−2 for the PEDOT:PSS film. Moreover, a photothermoelectric generator (PTEG) consisting of 36 legs of P_Ag@BP exhibits an open circuit voltage of 16.1 mV, a short circuit current of 47.9 μA, and an output power of 192.6 nW under 120 mW cm−2 illumination. Furthermore, when the PTEG is worn on the forearm and exposed to sunlight, it generates an output voltage of 9.2 mV, thus showcasing its potential application in wearable energy harvesting devices.