This chapter builds upon the thermal transport insights gained in the previous chapter and integrates them with electronic characterisation to explore thermoelectric performance in hybrid 2D–3D nanostructures. The main objective is to demonstrate how interfacial engineering can be used to simultaneously optimise charge and heat transport, thereby enhancing thermoelectric efficiency at room temperature. The first system investigated is a molybdenum disulphide/antimony telluride superlattice, where the structural composition is examined in detail, followed by measurements of its electronic transport properties and anisotropic thermal conductivities. This layered structure leverages the contrast between the electronic and phononic behaviours of its constituents to tailor the thermoelectric response. The second system is a silver/antimony telluride nanocomposite, analysed similarly through its electronic and thermal transport characteristics. In both cases, the combined analysis of the electrical and thermal conductivities as well as their interfacial interactions allows for the evaluation of the materials’ potential for energy harvesting applications. By correlating structural design with transport measurements, this chapter demonstrates the viability of low-dimensional heterostructures as platforms for thermoelectric optimisation, paving the way for more efficient solid-state energy conversion technologies.