Nickel Phthalocyanine: Borophene P-N Junction-Based Thermoelectric Generator

In this study, borophene and nickel phthalocyanine (NiPc): borophene nanocomposites were prepared using the sonication method. The NiPc: borophene nanocomposite was uniformly obtained as a 10-80 nm-sized spherically shaped particle. Electrical conductivities (s) were measured as 3 × 10^-13 Scm^-1 and 9.5 × 10^-9 Scm^-1 for NiPc and the NiPc: borophene nanocomposite, respectively. The SEM image showed that borophene was homogeneously distributed in the NiPc matrix and increased the charge transport pathways. This is the main reason for a 10⁶-fold increase in electrical conductivity. An indium tin oxide (ITO)/NiPc: borophene nanocomposite-based thermoelectric generator (TEG) was prepared and characterized. The Seebeck coefficients (S) were calculated to be 5 μVK^-1 and 30 μVK^-1 for NiPc and the NiPc: borophene nanocomposite, respectively. A positive Seebeck coefficient value for the NiPc: borophene showed the p-type nature of the nanocomposite. The power factors (PF = sS2) were calculated as 7.5 × 10^-16 μW m^-1 K^-2 and 8.6 × 10^-10 μW m^-1 K^-2 for NiPc and the NiPc: borophene nanocomposite, respectively. Compositing NiPc with borophene increased the power factor by ~10⁶-fold. It has been concluded that the electrical conductivity and Seebeck coefficient of the NiPc: borophene material increases due to energy band convergence because of combining p-type NiPc with p-type borophene. Therefore, the NiPc: borophene nanocomposite is a promising material for TEG.