Thermoelectric (TE) materials possess unique energy conversion capabilities between heat and electrical energy. Small organic semiconductors have aroused widespread attention for the fabrication of TE devices due to their advantages of low toxicity, large area, light weight, and easy fabrication. However, the low TE properties hinder their large‐scale commercial application. Herein, the basic knowledge about TE materials, including parameters affecting the TE performance and the remaining challenges of the organic thermoelectric (OTE) materials, are initially summarized in detail. Second, the optimization strategies of power factor, including the selection and design of dopants and structural modification of the dope‐host are introduced. Third, some achievements of p‐ and n‐type small molecular OTE materials are highlighted to briefly provide their future developing trend; finally, insights on the future development of OTE materials are also provided in this study.

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Active layer materials with silicone side chains have been broadly reported to have excellent long-term stability in harsh environments. However, the application of conjugated materials with silicone side chains in electron transport layers (ETLs) has rarely been reported. In this research, we synthesized for the first time a siloxane-modified perylene-diimide derivative (PDI-OSi) consisting of a side-chain substituent of siloxane and a conjugated group of perylene-diimide (PDI). The inserted siloxane functional groups not only can strengthen the light transmittance of PDI-OSi but also can remarkably expand its solubility and improve the filmforming ability and air stability of the material. Second, introducing siloxane-containing side chains can dramatically lower the work function and interfacial barrier of the electrode, thereby achieving a favorable ohmic contact. In addition, the moderate surface energy of siloxane functional groups makes PDI-OSi hydrophobic, which is conducive to forming excellent miscibility with hydrophobic active layers to promote charge transfer. When PDI-OSi is used as an ETL in organic solar cells (OSCs), operative exciton dissociation and more favorable surface morphology enable OSCs to realize a power conversion efficiency (PCE) of 13.99%. These results indicate that side-chain engineering with siloxane pendants is a facile strategy for constructing efficient OSCs.

The silicone rubber (SR) nanocomposites have been successfully prepared via the in situ hydrosilylation reaction in the presence of pristine ZnO and vinyl silane modified ZnO ( SiVi@ ZnO ) nanoparticles. The structure of the pristine ZnO and SiVi @ ZnO nanoparticles were analyzed by the Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), respectively. The morphology, thermal stabilities, mechanical properties and thermal conductivity of the nanocomposites were also investigated. The results showed that the SiVi @ ZnO nanoparticles exhibit a better dispersion in the silicone rubber than the pristine ZnO nanoparticles. The corresponding silicone rubber/ SiVi @ ZnO (SR/ SiVi @ ZnO ) nanocomposites showed higher mechanical properties and thermal conductivity due to the better dispersion in silicone rubber matrix.

The electron transport layers (ETLs) of non-fullerene organic solar cells (NOSCs) are crucial to modulate the work function (WF) of the electrode and restrict the recombination of electron-hole. Herein, two...