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Hybrid flexible thermoelectric (TE) materials are widely being explored for wearable TEs, micro power generators, and self‐powered electronics. The commonly used methods for developing hybrid flexible TE materials are organic–inorganic composite which exhibits low TE performance and second is inorganic material deposition over organic substrate making it a two‐sheet structure that has sustainability concerns. In view of this, herein, a different class of highly flexible hybrid TE materials are designed using a network of electrospun 1D nanofibers (NFs) as a substrate which provides high surface area, better connectivity, and high flexibility. For the proof of concept, the NFs sheets of two polymers polyacrylonitrile (PAN) and cellulose acetate are used to deposit the well‐known Bi2Te3as a case study. Herein, the directionally aligned PAN‐based NFs sheet exhibits good TE properties leading to the maximum PF ≈51.4 μW m−1K−2at 384 K for the P‐400 sample. Herein, the concept of a new class of hybrid TEs is successfully demonstrated by utilizing the flexible NF sheet as a substrate for inorganic TE materials, which will pave the way for sustainable flexible TE. Further, the TE performance can be enhanced by modulating certain factors such as the synthesis conditions of NFs and inorganic material, the thickness of deposition, and so on. A hybrid flexible thermoelectric is developed by utilizing the network of electrospun 1‐dimensional nanofibers. For proof of concept, the nanofiber sheets of two polymers polyacrylonitrile, and cellulose acetate are used to deposit the Bi2Te3. This type of hybrid structure paves the way for sustainable flexible thermoelectric.

Hybridizing topological materials (TM) with two-dimensional (2D) materials has resulted in interesting structures, such as van der Waals heterostructures (vdW), having potential in optoelectronics. However, the performance of devices made out of such structures relies on the charge carrier interactions among the layers, which establishes the basic trade-off between the kinetically controlled charge carrier dynamics at the interface and the performance of vdW-based devices. In this perspective, three vdW are fabricated using a wet transfer technique, and the structures are probed to study the charge carrier and phonon dynamics among the TM (a few layered Bi2Te3) and 2D systems. The three different vdW fabricated in this article are graphene/Bi2Te3(G/BT), fluorographene/Bi2Te3(FG/BT), and monolayer MoS2/Bi2Te3(MS/BT). Raman spectroscopy establishes the formation of all of these vdW and indicates the occurrence of the charge transfer (CT) phenomenon among them, which is further probed using ultrafast pump–probe spectroscopy. The charge carrier and phonon dynamics reveal the presence of the occurrence of the CT mechanism in all of the vdW. These spectra are further used to model the bands between different types of heterointerfaces, such as the Schottky junction between graphene and Bi2Te3and the type II heterojunction between FG/BT and MS/BT. With the help of band alignment and charge carrier and phonon dynamics studies presented, a unique CT mechanism and excitonic peak tunability in vdW are proven, where such information is essential in developing highly sensitive optoelectronic and spintronic devices